The things you see when ya go lookin'......
 

Those of you with a predilection for copious amounts of glass and iron in
your amplifiers go scrute this site thoroughly:

http://www.sacthailand.com/


See the fabulous range of choice - 300Bs and 2A3s in particular and tell me
there's no demand for these seriously *broken* amps....???


Then see the 'Swing 32' and 'Swing 40' speakers and tell me they *ain't*
Jerichos:

http://www.apah69.dsl.pipex.com/fostexfe206e/fostex.htm

http://www.apah69.dsl.pipex.com/show/L1070577.JPG

http://www.apah69.dsl.pipex.com/show/L1070580.JPG

:-)

(Serious valve freaks note the Ulyanov GM-70s, btw....)

And finally, just for a laff, make your way to the Kiwame resistor page and
clock the nice Fluke Multimeter and tell me it ain't *identical* (apart from
the yellow case) from my trusty old Maplins Pro4 meter:

http://www.apah69.dsl.pipex.com/show/Meter.JPG

:-)

The things you see when ya go lookin'......
 

"Keith G" wrote in message
...

Those of you with a predilection for copious amounts of glass and iron in
your amplifiers go scrute this site thoroughly:

http://www.sacthailand.com/


See the fabulous range of choice - 300Bs and 2A3s in particular and tell
me there's no demand for these seriously *broken* amps....???


Then see the 'Swing 32' and 'Swing 40' speakers and tell me they *ain't*
Jerichos:

http://www.apah69.dsl.pipex.com/fostexfe206e/fostex.htm

http://www.apah69.dsl.pipex.com/show/L1070577.JPG

http://www.apah69.dsl.pipex.com/show/L1070580.JPG

:-)

(Serious valve freaks note the Ulyanov GM-70s, btw....)

And finally, just for a laff, make your way to the Kiwame resistor page
and clock the nice Fluke Multimeter and tell me it ain't *identical*
(apart from the yellow case) from my trusty old Maplins Pro4 meter:

http://www.apah69.dsl.pipex.com/show/Meter.JPG

:-)


Keith, congratulations:- An audio-relevant post on this ng.......

I don't think anyone has suggested there isn't a demand for these types of
amps, but then these things go in fashions. It certains avoids the
manufacturer having to worry that their products will meet tight
specs........

One oddity I've noticed. On the SILK attenuator pages, they say of
conventional resistor attenuators "That's why at high attenuation level (low
signal out, low listening level) the bandwidth of such volume control is
very poor and the bandwidth is not constant over any switch position."

This is only relevant if using very long high-capacitance cables. If using
cables of normal capacitance, and of normal domestic lengths, it has no
relevance as the bandwidth is already well in excess of the audio bandwidth.
Although I think a multi-tapped transformer as an attenuator is a bit of
overkill, it is a theoretically sound solution as the output impedance will
reduce as the attenuation increases. Pity they couldn't have 23 separate
secondaries, and keep the whole thing balanced input to output. Now that
*would* have given them a winding challenge!


They are AudioNote distributors..... nuff said....

As to the Maplins meter, there is a whole raft of Chinese OEM product
available for badging. I can't see why Fluke shouldn't do it like Maplins.
Going back a few years, before China became the manufacturing centre of the
World, thre was a magazine called JEI, the journal of the Japanese
Electronics Industry. In there you could find almost anything you wanted to
badge, provided you bought enough of them. I was particularly amused to see
several of the pick-up arms and cartridges sold by turntable manufacturers
as their standard product in the JEI.

Anyway, the SAC stuff looks nice, and if you like that sort of thing, I'm
sure it will give pleasure.

S.

The things you see when ya go lookin'......
 

"Keith G" wrote in message
...

Those of you with a predilection for copious amounts of glass and iron in
your amplifiers go scrute this site thoroughly:

http://www.sacthailand.com/


See the fabulous range of choice - 300Bs and 2A3s in particular and tell
me there's no demand for these seriously *broken* amps....???


Keith. This is something that has been puzzling me for a very long time.
My local dealer tells me that the interest in single-ended is unprecidented.
and that second hand quality valve PP amps, particularly Quad, Radford and
McIntosh are especially "hot" items.

What does that tell us????

Iain

The things you see when ya go lookin'......
 

Regarding attenuators, I've been looking at alternatives for tube
equipment. As I see it:
- autoformer attenuators need such low impedence in that you're looking
at big caps before them to stop the DC. So anything you gain on the
autoformer you lose on the cap. I use russian teflon caps of 0.1uf
value, so I'm not keen on large multiples of them. I'm OK with up to
..3, maybe .5 in extremis.
- true transformer attenuators are interesting - eliminates the cap if
it allows DC.
- On the other hand you could, in balanced mode, just use a PP output
stage for the line out, and position the volume control after that - no
cap.
- Cap before stepped attenuator is what I use right now. It works, and
sounds good with teflon caps. My line stage is balanced, so I use a
shunt attenuator between legs, which in the present case is 47K shunt
with two series resistors of 22K before it, one in each leg. So the
resistance in the stepped attenuator isn't exactly constant.
- for convenience of input between SE and balanced, the next way I'm
going to build is integrated mono amps with stepped attenuator after
the first valve stage. this means I can use the same shunt attenuator,
but I can accept input as SE or balanced, depending on whether or not I
earth the second grid of the input pair.
Thoughts and ideas? Andy

The things you see when ya go lookin'......
 

"Serge Auckland" wrote


Keith, congratulations:- An audio-relevant post on this ng.......


Once in a while I manage to get one loosely on-topic....!! ;-)


I don't think anyone has suggested there isn't a demand for these types of
amps, but then these things go in fashions.


Possibly, but I think we're looking at decades for complete trend swings. My
guess is SE is back for a while now - especialli in the East.


It certains avoids the
manufacturer having to worry that their products will meet tight
specs........


Well, all I can say is that earlier this evening I was running the German PP
against one of the SETs and there's *no way* I'd pick the PP if it was an
'either or' situation....???



One oddity I've noticed. On the SILK attenuator pages, they say of
conventional resistor attenuators "That's why at high attenuation level
(low signal out, low listening level) the bandwidth of such volume control
is very poor and the bandwidth is not constant over any switch position."

This is only relevant if using very long high-capacitance cables. If using
cables of normal capacitance, and of normal domestic lengths, it has no
relevance as the bandwidth is already well in excess of the audio
bandwidth. Although I think a multi-tapped transformer as an attenuator is
a bit of overkill, it is a theoretically sound solution as the output
impedance will reduce as the attenuation increases. Pity they couldn't
have 23 separate secondaries, and keep the whole thing balanced input to
output. Now that *would* have given them a winding challenge!


I'm sure if there was enough of a potential market for them they would offer
them thus. I thought the Silk transformers at least *looked* the blx and the
website is very good with plenty of pictorial information - always a good
thing in my book!!



They are AudioNote distributors..... nuff said....


I have an 'efriend' who is a bit susceptible to AN stuff. I pointed out to
him the following, earlier this evening:

AN TT1 = Systemdek

AN Arm1/2/3 = Rega

AN IQ2 = Goldring

Then he was asking me about Linn, so I told him Linn Decks werre Ariston
ripoffs with Audio Technica arms and carts!

(I hope that wasn't too far from the truth!!)


As to the Maplins meter, there is a whole raft of Chinese OEM product
available for badging. I can't see why Fluke shouldn't do it like Maplins.

I bet my Maplins version was a lot cheaper than the Fluke!!


Going back a few years, before China became the manufacturing centre of
the World, thre was a magazine called JEI, the journal of the Japanese
Electronics Industry. In there you could find almost anything you wanted
to badge, provided you bought enough of them. I was particularly amused to
see several of the pick-up arms and cartridges sold by turntable
manufacturers as their standard product in the JEI.

:-)

See above re. 'Brand Name Bull****'...!!


Anyway, the SAC stuff looks nice, and if you like that sort of thing, I'm
sure it will give pleasure.


I thought the whole site was very appealing! - *Thailand* this one, don't
forget!!

(Scary innit?? :-)

The things you see when ya go lookin'......
 

"Andy Evans" wrote in message
oups.com...
The Silk stuff is nice, and the James as well.


And 'Custom Made To Order'!! If Pat Turner sees this site he'll have a fit!!
:-)

Did you see also:

"
SACThailand presents

UDC400 Class-D power amplifier with 200 watt RMS/CH"...???

I tell ya, these buggers have only just *started* to take the ****!! :-)


but all this fixation on
300b amps tends to lose the plot a bit. So as to sell an amp as a "DHT
amp" what's being done is to plonk the 300b or sometimes 2a3 or
sometimes 845 into the output and then fill the input stages with
mediocre 9 pin triodes - 12AU7, 12AT7, 12AX7 and the like. If you're
lucky you get a 5687 or a 6SN7. But when we take into account the fact
that the first two stages have a strong influence on the final sound,
it makes just as much sense to start with a 26 DHT - that's what I've
done and the effect is considerably more than I expected. Even better,
for a driver use a 46 or a 71A. While everyone is thinking "300b" I'm
quietly buying up some DHTs before they're too expensive - they sure
are going up in price, driven partly by the old radio collectors who
need them to fire up their old sets. My 26 line stage is a real
challenge - I'm building some Ronan Regs for the filaments - a lot of
work but it's seriously worth it. One day, Keith, you'll discover 26
line stages and say "why didn't I use that before"!!!! Andy


:-)

OK, but I gotta say my (possible) future amp plans would probably be more
along the lines of a top-flight 300B with '****-off' iron.....

(Not only is that on the back burner, but the cooker ain't even switched
on!!)

The things you see when ya go lookin'......
 

"Iain Churches" wrote in message
...

"Keith G" wrote in message
...

Those of you with a predilection for copious amounts of glass and iron in
your amplifiers go scrute this site thoroughly:

http://www.sacthailand.com/


See the fabulous range of choice - 300Bs and 2A3s in particular and tell
me there's no demand for these seriously *broken* amps....???


Keith. This is something that has been puzzling me for a very long time.
My local dealer tells me that the interest in single-ended is
unprecidented.
and that second hand quality valve PP amps, particularly Quad, Radford and
McIntosh are especially "hot" items.

What does that tell us????



Well, add that info to the *many* sites like the SAC Thailand site I
referenced and I would say the future's looking very bright for valves in
audio!!

Valves or SS, the better legacy 'names' are commanding big money everywhere
(as your dealer is telling you and as the two Sugdens I was watching on eBay
told me) and I suspect you could easily sell empty cardboard boxes with the
names Tannoy or Lowther on them these days! But I hesitate to suggest why
there is great interest in SE - obviously it could be a 'sound quality'
thing (as it is for me) but there's no escaping the increased publicity and
much easier availability of SET amps will have some effect?

(One thing's for certain - they won't be buying them on the basis of spec
sheets, as so many here will tell you!! :-)

I think it's all very healthy - a number of the people I 'speak to' who are
getting (or have just got) valve amps are quite young, so it's not a
'nostalgia thing' for them and, if it is simply a question of free choice
falling in favour of valves, then all I can safely say is 'Well, it ain't
just me!'!!

:-)

The things you see when ya go lookin'......
 

OK, but I gotta say my (possible) future amp plans would probably be
more along the lines of a top-flight 300B with '****-off' iron.....

This is what I'm saying - you're thinking the end of the chain rather
than the start - everything goes through the input! You're amp is
ultimately never going to be better than the first two stages - put
ECC**s in it and its an ECC** amp.

The things you see when ya go lookin'......
 

"Andy Evans" wrote in message
oups.com...
OK, but I gotta say my (possible) future amp plans would probably be
more along the lines of a top-flight 300B with '****-off' iron.....

This is what I'm saying - you're thinking the end of the chain rather
than the start - everything goes through the input! You're amp is
ultimately never going to be better than the first two stages - put
ECC**s in it and its an ECC** amp.


Andy. I must agree with you that "octals have the magic"
but good results can be obtained with miniature nin-pin valves too.
I believe it is the topology that is most important.

People rattle on about "the dreadful high-gain minature pentode"
but seem to forget that both Peter Walker and Arthur Radford
understood its use in amplifiers which still perform exceptionally
well to this day.

I would think that when Keith begins to think about his top-flight
300B amp, miniature triodes will be conspicuous in their
absence:-)

Regards to all
--
Iain
www.kolumbus.fi/iain.churches

The things you see when ya go lookin'......
 

"Keith G" wrote in message
...

"Iain Churches" wrote in message
...


Keith. This is something that has been puzzling me for a very long time.
My local dealer tells me that the interest in single-ended is
unprecidented.
and that second hand quality valve PP amps, particularly Quad, Radford
and
McIntosh are especially "hot" items.

What does that tell us????

Well, add that info to the *many* sites like the SAC Thailand site I
referenced and I would say the future's looking very bright for valves in
audio!!

Valves or SS, the better legacy 'names' are commanding big money
everywhere (as your dealer is telling you and as the two Sugdens I was
watching on eBay told me) and I suspect you could easily sell empty
cardboard boxes with the names Tannoy or Lowther on them these days!

:-) Indeed. I am happy to have a workshop full of worthless
old retro crap:-))

But I hesitate to suggest why there is great interest in SE - obviously it
could be a 'sound quality' thing (as it is for me) but there's no escaping
the increased publicity and much easier availability of SET amps will have
some effect?

It seems that people find SET pleasing in a musical way.
However, I am not sure if the Chinese presence is a good or a bad
thing. These amps do perhaps give people an "entry level" perspective
into thermionic audio, but at the same time the modest performance
may give the wrong impression of what a valve amp can do.

Few valve amps from Asia are sold through dealers, and so have
very questionable warranty rights. The component and build quality
is not too good at the moment (it will take them a while to get it right)
so failures within the first year are commom. This too creates a negative
impression.

I think it's all very healthy - a number of the people I 'speak to' who
are getting (or have just got) valve amps are quite young, so it's not a
'nostalgia thing' for them and, if it is simply a question of free choice
falling in favour of valves, then all I can safely say is 'Well, it ain't
just me!'!!

There was a whole generation that missed out on thermionic audio.

The members of the music appreciation group to which I belong
(now twenty two strong) have thirteen valve power amps between
them. These people are very serious listeners, so a thermionic
presence well in excess of 50% speaks for itself.


Iain

The things you see when ya go lookin'......
 

"Iain Churches" wrote in message
...

"Serge Auckland" wrote in message
...

One oddity I've noticed. On the SILK attenuator pages, they say of
conventional resistor attenuators "That's why at high attenuation level
(low signal out, low listening level) the bandwidth of such volume
control is very poor and the bandwidth is not constant over any switch
position."

This is only relevant if using very long high-capacitance cables. If
using cables of normal capacitance, and of normal domestic lengths, it
has no relevance as the bandwidth is already well in excess of the audio
bandwidth. Although I think a multi-tapped transformer as an attenuator
is a bit of overkill, it is a theoretically sound solution as the output
impedance will reduce as the attenuation increases. Pity they couldn't
have 23 separate secondaries, and keep the whole thing balanced input to
output. Now that *would* have given them a winding challenge!´

Serge. I have just built a passive preamp to *exactly* the specification
you quote above - multiple secondaries -balanced line throughout.

It's brilliant:-)

Iain

Interesting! Did you wind your own transformer? What secondary load are
you driving? I presume it's 10k bridging rather than 600 ohm terminating.

S.

The things you see when ya go lookin'......
 

"Serge Auckland" wrote in message
...

"Iain Churches" wrote in message
...

"Serge Auckland" wrote in message
...

One oddity I've noticed. On the SILK attenuator pages, they say of
conventional resistor attenuators "That's why at high attenuation level
(low signal out, low listening level) the bandwidth of such volume
control is very poor and the bandwidth is not constant over any switch
position."

This is only relevant if using very long high-capacitance cables. If
using cables of normal capacitance, and of normal domestic lengths, it
has no relevance as the bandwidth is already well in excess of the audio
bandwidth. Although I think a multi-tapped transformer as an attenuator
is a bit of overkill, it is a theoretically sound solution as the output
impedance will reduce as the attenuation increases. Pity they couldn't
have 23 separate secondaries, and keep the whole thing balanced input to
output. Now that *would* have given them a winding challenge!´

Serge. I have just built a passive preamp to *exactly* the specification
you quote above - multiple secondaries -balanced line throughout.

It's brilliant:-)

Iain

Interesting! Did you wind your own transformer? What secondary load are
you driving? I presume it's 10k bridging rather than 600 ohm terminating.



Wound for me at a local broadcast engineering workshop.
(I have friends in low places:-)

Nominal impedance 10k.
48dB attentuation in 2dB steps.
Inductance 80H.

Iain

The things you see when ya go lookin'......
 

"Andy Evans" wrote in message
oups.com...
OK, but I gotta say my (possible) future amp plans would probably be
more along the lines of a top-flight 300B with '****-off' iron.....

This is what I'm saying - you're thinking the end of the chain rather
than the start - everything goes through the input! You're amp is
ultimately never going to be better than the first two stages - put
ECC**s in it and its an ECC** amp.



Andy, I've got nothing against miniatures other than I think they look weedy
in the same chassis as 300Bs - see my cheepy chinky #01:

http://www.apah69.dsl.pipex.com/bez/Bez047.JPG

- one thing I like about it is has nice fat little 'knobber' valves in the
front line up. Another thing I like about is that I have just swapped it in
on my new speakers and it ****es over the Dynavox I had on them beforehand!
It's simple for me - if it's 'horns', it IS triodes (*end of*)....!!

(One thing I have noticed btw, is swapping mulitary Millards for the Chinee
CF2s on the Dynavox brought forth *no* discernable improvement...??!!)

On that subject....

Out with the old:

http://www.apah69.dsl.pipex.com/show/L1070646.JPG

and in with the new:

http://www.apah69.dsl.pipex.com/show/L1070649.JPG

:-)

Staggering performance now (the Visatons **** on the Fostex in these
cabinets) and my door frame is once again *thrumming* to the end of Blade
Runner, Track 1 as I type!! (Not too ****e for 4 inch drivers!! :-))

I'm hoping 'one here' will be a very happy bunny when he hears these!! (Or
I've got another pair I will be very happy to keep!! :-)

But I digress...

Back to your exhortations - fear ye not Andy, I have a pair of brand new
Sovtek 6SN7GTs (you know - the ones with the wonky glass) that have been
waiting very patiently for the last couple of years to have the right amp
slid underneath them!!

;-)

The things you see when ya go lookin'......
 

"Keith G" wrote in message
...

"Andy Evans" wrote in message
oups.com...
OK, but I gotta say my (possible) future amp plans would probably be
more along the lines of a top-flight 300B with '****-off' iron.....

This is what I'm saying - you're thinking the end of the chain rather
than the start - everything goes through the input! You're amp is
ultimately never going to be better than the first two stages - put
ECC**s in it and its an ECC** amp.



Andy, I've got nothing against miniatures other than I think they look
weedy in the same chassis as 300Bs - see my cheepy chinky #01:

http://www.apah69.dsl.pipex.com/bez/Bez047.JPG


Agreed. Miniatures are fine with EL84s or even EL34's but when
you get up to KT88s or 300B size, then only octals look right:-)

Back to your exhortations - fear ye not Andy, I have a pair of brand new
Sovtek 6SN7GTs (you know - the ones with the wonky glass) that have been
waiting very patiently for the last couple of years to have the right amp
slid underneath them!!

Now your're tallking:-)

Iain

The things you see when ya go lookin'......
 

"Iain Churches" wrote in message
...

"Andy Evans" wrote in message
oups.com...
OK, but I gotta say my (possible) future amp plans would probably be
more along the lines of a top-flight 300B with '****-off' iron.....

This is what I'm saying - you're thinking the end of the chain rather
than the start - everything goes through the input! You're amp is
ultimately never going to be better than the first two stages - put
ECC**s in it and its an ECC** amp.


Andy. I must agree with you that "octals have the magic"
but good results can be obtained with miniature nin-pin valves too.
I believe it is the topology that is most important.

People rattle on about "the dreadful high-gain minature pentode"
but seem to forget that both Peter Walker and Arthur Radford
understood its use in amplifiers which still perform exceptionally
well to this day.

I would think that when Keith begins to think about his top-flight
300B amp, miniature triodes will be conspicuous in their
absence:-)



Yes - see my reply to Andy. From the POV of physical 'size' and
'aesthetics', if nothing else!!

With the cost of a 'superamp project' in my mind there, my thoughts
immediately went to the recent robbery of 25 million quid mentioned on the
news just now. Apparently the Police are watching the airports for people
trying to move large amounts of cash abroad!!??

Larf? - I nearly lost me lunch!!

(It's gets fekkin' *sillier* every single day......!!!!)

:-))

The things you see when ya go lookin'......
 

Keith G wrote:
OK, but I gotta say my (possible) future amp plans would probably be more
along the lines of a top-flight 300B with '****-off' iron.....

(Not only is that on the back burner, but the cooker ain't even switched
on!!)

Keith:

Given on the assumption that by "'****-off' iron" you mean the very
best transformers, regardless of price:

Ever hear of the concept in economics of marginality? Technically it is
used to determine at which price per unit a perfect market clears. But
on the ground, and in core theory, it depends on the perception of
individuals about which products are worth more money because they give
greater satisfaction than the possession of the money. A corollary is
that greater and greater amounts of money at each step buy lesser and
lesser *increases* in satisfaction.

Your dream on the backburner is on the face of it not a bad idea. For
instance, many of us own absolutely better tube amps than you do, and
in a large number of cases we can afford them only because we built
them ourselves. We consider the expenditure worthwhile, and the
pleasure of something of (often) our own design and construction adds
to the value perceived. However, you should not fall into the trap of
thinking that the difference between your cheap Chinese and our cheap
DIY at several times the price of cheap Chinese is a gulf the size of
the Grand Canyon. It is a marginal, incremental difference. Think about
it: you have already arrived in the top one half of one percent of
hi-fi; at this level of hi-fi, all margins are minutely incremental and
very expensive.

We would find it a hardship to listen to your cheap chinese rather than
our cheap DIY. That is because we are used to what we have now and,
important this, have paid for it already and justified the cost to
ourselves.

You, having accustomed yourself to the cheap Chinese, and justified it
many times over, may be disappointed after paying several times the
cost of the cheap Chinese to discover that for so much money you have
gained only a small improvement in your sound.

At that, you will be in a better position than someone who has to lash
out ten times the price of the cheap Chinese to buy a good European or
American or Japanese tube amp on the open market. The difference will
come not only from the saved money but from the intrinsic DIY
satisfaction, which shines through your posts.

None of this will stop you if you really intend to go ahead.

*****

When you do go ahead, here's a tip. If you really want "****-you iron",
give the boutique hypesters a miss and buy your iron by the pound.
Literally. I mean it. The best transformer designers and builders earn
most of their basic bread, and a good bit of their jam, from the
national broadcasters. In essence, they give you their expertise for
free because the broadcasters have paid for skill development and
product development.

As an extreme example of buying transformers by the pound, hire one of
the poorer tranny designers (Patrick Turner is good and agreable if you
stroke him right) to run up a specification for you, take it to your
local generator rewinders, and let them do the job to save the
carriage. Or buy the designs of famous audio transformer designers off
the shelf. Amplimo and Plitron sell the designs of Menno van der Veen,
the best audio transformer designer now alive. Or Simon Shilton (who
may look like a boutique to the uninformed but whose transformer
designs are on many commercial amps with big names) sells a few of his
designs to the public at reasonable prices for what are essentially
custom designs (I can also recommend his DIY amp designs for which the
transformers are intended). But the best price/performance ratio is
without a doubt the Cut C-Core transformers made by Lundahl of Sweden.
In blind listening tests we ran they were chosen over the elite
Japanese transformers at many times the price. The Lundahls are only
one or two steps above the bottom rung in price, they're
ultra-adaptable, and they measure and sound as good as the very best.
The downside is that they look like what they are (industrial
artififacts from the hidden end of the broadcast industry) but what the
hell, Lundahl will sell you a can to pot them in if you insist on
having your transformers on display. Many of the highest-profile DIY
tube amp designers in the world swear by Lundahl transformers.

HTH.

Andre Jute
Visit Jute on Amps at http://members.lycos.co.uk/fiultra/
"wonderfully well written and reasoned information
for the tube audio constructor"
John Broskie TubeCAD & GlassWare
"an unbelievably comprehensive web site
containing vital gems of wisdom"
Stuart Perry Hi-Fi News & Record Review

The things you see when ya go lookin'......
 

"Iain Churches" wrote in message
...

"Keith G" wrote

Valves or SS, the better legacy 'names' are commanding big money
everywhere (as your dealer is telling you and as the two Sugdens I was
watching on eBay told me) and I suspect you could easily sell empty
cardboard boxes with the names Tannoy or Lowther on them these days!

:-) Indeed. I am happy to have a workshop full of worthless
old retro crap:-))


:-)


But I hesitate to suggest why there is great interest in SE - obviously
it
could be a 'sound quality' thing (as it is for me) but there's no
escaping
the increased publicity and much easier availability of SET amps will
have
some effect?

It seems that people find SET pleasing in a musical way.


Yes, this is fundamental. A better, more *pleasing* sound is what it's all
about AFAIAC....

It needs to be clearly stated that not everyone will like the SET/Horn
combination - I do, but then then I'm not overly endowed with the *technical
knowledge* that makes this 'difficult' for some people...!! ;-)



However, I am not sure if the Chinese presence is a good or a bad
thing. These amps do perhaps give people an "entry level" perspective
into thermionic audio, but at the same time the modest performance
may give the wrong impression of what a valve amp can do.


If valve amps are simply too expensive for impoverished/curious types, they
will never join the growing legions of 'thermionophiles'. I'm fairly sure,
that once they have got their feet wet, they will be curious about 'better
amps' and, now that valves are almost parallel with SS stuff on prices, a
clear upgrade path becomes visible presenting some interesting options. This
is where you come in - as a specialist builder in Europe, you have a hundred
quid advantage over Far Eastern competition on shipping costs alone. (It's
not for nothing that current 'modern' audio gear from the East weighs
*ounces*...)

(Not so in the 'Podes, though - poor old Pat "Lend Us A Shag 'Til I Get
Paid" Turner is stoked. Over there they are buying dirt girt Chinese valve
amps with big squidgy feet for the sole purpose of flattening out out their
warped vinyl, I gather!! ;-)

Either way, valve amp builders will have to do more to convince the buying
public that they are offering superior quality now that they are up against
stiff competition - it's possibly harsh and will probably weed out out a few
of the weaker players, but it's for the good of all, ultimately!!

(Luckily, even a modest valve amp has little or no trouble seeing off
similarly-priced SS competition, from what I can see/hear of it! ;-)


Few valve amps from Asia are sold through dealers, and so have
very questionable warranty rights. The component and build quality
is not too good at the moment (it will take them a while to get it right)
so failures within the first year are commom. This too creates a negative
impression.


Warranties from Chinese dealers (eBay) are *worthless* - when my volume pot
went tits up the dealer (Edmund Lam, aka 'Zagger1' on Fleabay) promised a
replacement - it never arrived. When I pointed this out to him after some
weeks, he promised to put another in the post - guess what....??

I have always said that people who can't fettle a valve amp shouldn't risk
the more exotic examples from the Far East. IME, European valve amps (very
likely *made* in China) like the (bullet proof?) Dynavox are a much safer
'entry option'....



I think it's all very healthy - a number of the people I 'speak to' who
are getting (or have just got) valve amps are quite young, so it's not a
'nostalgia thing' for them and, if it is simply a question of free choice
falling in favour of valves, then all I can safely say is 'Well, it ain't
just me!'!!

There was a whole generation that missed out on thermionic audio.


I almost did. Obviously, radios and record players (stereograms) were valves
when I wuz a kid, but I wasn't taking much notice. Maybe I have/had
deep-seated/ingrained memories of the sound quality and was trying
unsuccessfully to find it with SS gear??


The members of the music appreciation group to which I belong
(now twenty two strong) have thirteen valve power amps between
them. These people are very serious listeners, so a thermionic
presence well in excess of 50% speaks for itself.


AFAIAC, disregarding the excellent little Sony AV amp on the telly setup,
with my own amps currently running at 100% valve, it most certainly *does*
speak for itself!!

;-)

The things you see when ya go lookin'......
 

Iain Churches wrote:
"Andy Evans" wrote in message
oups.com...
OK, but I gotta say my (possible) future amp plans would probably be
more along the lines of a top-flight 300B with '****-off' iron.....

This is what I'm saying - you're thinking the end of the chain rather
than the start - everything goes through the input! You're amp is
ultimately never going to be better than the first two stages - put
ECC**s in it and its an ECC** amp.


Andy. I must agree with you that "octals have the magic"
but good results can be obtained with miniature nin-pin valves too.
I believe it is the topology that is most important.

People rattle on about "the dreadful high-gain minature pentode"
but seem to forget that both Peter Walker and Arthur Radford
understood its use in amplifiers which still perform exceptionally
well to this day.

I would think that when Keith begins to think about his top-flight
300B amp, miniature triodes will be conspicuous in their
absence:-)

Regards to all
--
Iain
www.kolumbus.fi/iain.churches

The things you see when ya go lookin'......
 

Iain Churches wrote:
"Andy Evans" wrote in message
oups.com...
OK, but I gotta say my (possible) future amp plans would probably be
more along the lines of a top-flight 300B with '****-off' iron.....

This is what I'm saying - you're thinking the end of the chain rather
than the start - everything goes through the input! You're amp is
ultimately never going to be better than the first two stages - put
ECC**s in it and its an ECC** amp.


Andy. I must agree with you that "octals have the magic"

Nothing more linear than a 6SN7, nothing more agreeable to the ear than
a 6SL7, and in combination unbeatably balanced. Check out Steve Bench's
site where he shows a bunch of driver topologies with measurements.

but good results can be obtained with miniature nin-pin valves too.
I believe it is the topology that is most important.

I like two of the miniatures, if by miniatures we mean 9-pin tubes.

My alltime fave driver is the WE417A, also made as the 5842 by many
others, including Ericson of Sweden, so generally available cheaply. Mu
over 40, up to 24mA, a Miller-capacitance killeer par excellence.



People rattle on about "the dreadful high-gain minature pentode"

....And for a CCS made with tubes rather than transistors, the EL84 is a
super tube.

but seem to forget that both Peter Walker and Arthur Radford
understood its use in amplifiers which still perform exceptionally
well to this day.

The EF86 is as often misapplied as it is maligned, and usually the
former precedes the latter!

I would think that when Keith begins to think about his top-flight
300B amp, miniature triodes will be conspicuous in their
absence:-)

If you're spending top dollar anyway, you may as well get an NOS double
digit triode for your driver. Andy has a list about which he has been
going on for a while, and a visit to Jim de Kort's VT52 site is
instructive. I drive SV572-3 and -10 and other kilovolt class tubes
with a 300B which is itself driven by a 417A which is driven via a pot
direct from the CD player: three stages total.

A sweet tube that is often overlooked (in these parts -- it has a
certain vogue in Japanese ultrafi circles) as a driver for a DHT is a
trioded EL34.

Regards to all
--
Iain
www.kolumbus.fi/iain.churches

HTH.

Andre Jute
Visit Jute on Amps at http://members.lycos.co.uk/fiultra/
"wonderfully well written and reasoned information
for the tube audio constructor"
John Broskie TubeCAD & GlassWare
"an unbelievably comprehensive web site
containing vital gems of wisdom"
Stuart Perry Hi-Fi News & Record Review

The things you see when ya go lookin'......
 

On Thu, 23 Feb 2006 14:25:01 -0000, "Keith G"
wrote:

I'm hoping 'one here' will be a very happy bunny when he hears these!!

slurps loudly ...

Cessna172

The things you see when ya go lookin'......
 

"Cessna172" wrote in message
...
On Thu, 23 Feb 2006 14:25:01 -0000, "Keith G"
wrote:

I'm hoping 'one here' will be a very happy bunny when he hears these!!

slurps loudly ...

Cessna172


**** me - I was going to add a bit about 'the only Cessna fitted with
Lancaster undercarriage gear' to wind Ray up (he knows why! :-) and I
Googled 'Lancaster Bomber':

http://www.lancastermuseum.ca/lancbomber.html

Where I read this:

"During World War II the Lancaster was the most successful bomber used by
the Royal Air Force and the Royal Canadian Air Force.The Lanc had speed,
ceiling, and lifting power that no other aircraft of the day could match.
Weighing 36,900 pounds empty, the Lancaster was capable of taking off with
an additional 33,100 pounds of fuel and bombs; in other words it could
almost carry its own weight again. The Lancaster carried 64% of the tonnage
dropped by the RAF and RCAF during the war. The "Grand Slam", a 22,000 pound
special purpose bomb designed to penetrate concrete and explode below the
surface to create an earthquake effect, could only be delivered by the
Lancaster and the Lancaster was thus chosen for special operations such as
the "Dambusters" raid and the attack which sunk the German Battleship
Tirpitz."

"it could almost carry its own weight again"....!!!!

!!!!

Now *that's* what I call *engineering*!! (Feck, you gotta take your hat off
to these people - and no silly, sodding PCs available in those days!!)

Read the whole thing - gave me bloody goosebumps!!

"The Lancaster won the naval war by destroying over one-third of the German
submarines in their ports,
together with hundreds of small naval craft and six of their largest
warships."

Anyway, where wuz I?

Oh yes - Ray, you'd better bring that bloody sand amp of your up here (and a
bit of 'reference' music).

Remember Laurie Anderson 'Life On A String' Track 1 when you come and I'll
*show* you a 7/8 watt amp on 4 inch speakers making the the bloody door
frame *shudder*!! Gimme a shout direct when would be convenient - 'first
fitting' only, no fancy finishes!! ;-)

The things you see when ya go lookin'......
 

"Keith G" wrote

**** me - I was going to add a bit about 'the only Cessna fitted with
Lancaster undercarriage gear' to wind Ray up (he knows why! :-) and I
Googled 'Lancaster Bomber':

http://www.lancastermuseum.ca/lancbomber.html


I'm still freaked out by this site - see this also:

"The new bomber was immediately regarded as a success and large production
orders were placed. Avro's production facilities were soon overwhelmed, and
numerous other companies and contractors joined the effort to produce
Lancasters. Consisting of 55 000 separate parts, it has been estimated that
half a million different manufacturing operations were involved to produce
just one aircraft. Peak production was achieved during August 1944 when 293
aircraft were produced."


Jeez....

I'm gobsmacked - am I easily impressed or summat?

(I don't think today's muppets could *describe* that sort of
productivity/effort - let alone *do* it!!)

The things you see when ya go lookin'......
 

On 23 Feb 2006 07:37:16 -0800, "Andre Jute" wrote:

But the best price/performance ratio is
without a doubt the Cut C-Core transformers made by Lundahl of Sweden.
In blind listening tests we ran they were chosen over the elite
Japanese transformers at many times the price. The Lundahls are only
one or two steps above the bottom rung in price, they're
ultra-adaptable, and they measure and sound as good as the very best.
The downside is that they look like what they are (industrial
artififacts from the hidden end of the broadcast industry) but what the
hell, Lundahl will sell you a can to pot them in if you insist on
having your transformers on display. Many of the highest-profile DIY
tube amp designers in the world swear by Lundahl transformers.

While I would generally hesitate to agree with Jute, he is in this
case quite right. If you really must build a valve amplifier, then the
Lundahl range of transformers does indeed provide excellent
performance at realistic prices. This allows you to go for a more
optimised design than might otherwise be possible, particularly if for
some reason you decide to go down the technically crippled
single-ended route, with its horrific implications regarding core
saturation. Ya need seriously gang-banging iron for those suckers!

Basically, always buy a trannie that will handle a little more power
than you are designing for, rather than a little less. Your bottom end
will be eternally grateful...................
--

Stewart Pinkerton | Music is Art - Audio is Engineering

The things you see when ya go lookin'......
 

"Stewart Pinkerton" wrote in message
...
On 23 Feb 2006 07:37:16 -0800, "Andre Jute" wrote:


While I would generally hesitate to agree with Jute, he is in this
case quite right. If you really must build a valve amplifier, then the
Lundahl range of transformers does indeed provide excellent
performance at realistic prices. This allows you to go for a more
optimised design than might otherwise be possible, particularly if for
some reason you decide to go down the technically crippled
single-ended route, with its horrific implications regarding core
saturation. Ya need seriously gang-banging iron for those suckers!

Basically, always buy a trannie that will handle a little more power
than you are designing for, rather than a little less. Your bottom end
will be eternally grateful...................
--

Keith has a good alternative to Lundahl, and practically on his doorstep.
- AE Sowter Ltd.

Iain

The things you see when ya go lookin'......
 

"Keith G" wrote in message
...

"Iain Churches" wrote in message
...


G'd evening Keith!

I have just come back from a pleasant few hours fettling in my den of
excellence. A CCS cathode follower is bubbling nicely on the front
burner:-)

It seems that people find SET pleasing in a musical way.

Yes, this is fundamental. A better, more *pleasing* sound is what it's all
about AFAIAC....

Yes. My pal Peter Lewis used to call it the M (musicality) factor.
Peter was a design engineer at Leevers Rich, in the UK. He was a "real"
(not just an NG armchair) engineer, in that he was constantly building
and trying out something. He made a very good living even after retirement
building bespoke valve amps for discerning clients. He could offer the
features and attention to detail which no larger maker can offer.

It needs to be clearly stated that not everyone will like the SET/Horn
combination - I do, but then then I'm not overly endowed with the
*technical knowledge* that makes this 'difficult' for some people...!!
;-)

Hmm. Once the technical performance has been assessed,
and we know what the amp can (or cannot) do, why not sit back and
enjoy what it has to offer?

If valve amps are simply too expensive for impoverished/curious types,
they will never join the growing legions of 'thermionophiles'. I'm fairly
sure, that once they have got their feet wet, they will be curious about
'better amps' and, now that valves are almost parallel with SS stuff on
prices, a clear upgrade path becomes visible presenting some interesting
options.

Yes. Interesting point. My dealer pal tells me that he can offer an
entry level valve amp for about the same money as a mid price SS system.
From then on, the only way is up :-)

(Not so in the 'Podes, though - poor old Pat "Lend Us A Shag 'Til I Get
Paid" Turner is stoked. Over there they are buying dirt girt Chinese valve
amps with big squidgy feet for the sole purpose of flattening out out
their warped vinyl, I gather!! ;-)

Patrick is very smart. He keeps his outfit small, and offers a very good
build and repair service. He has an enviable reputation, and customers
recommend him to others, and keep coming back. His amplifiers are
excellent examples of "tube-craft". He is a very nice guy too, and always
ready with help and advice when asked.

Either way, valve amp builders will have to do more to convince the buying
public that they are offering superior quality now that they are up
against stiff competition - it's possibly harsh and will probably weed out
out a few of the weaker players, but it's for the good of all,
ultimately!!

Yes agreed. The problem is one of volume. I am told that there are
ten different brands of Chinese/Taiwanese/Thai amps all almost identical
and built in the same factory. Isn't that what British Leyland used to call
"badge engineering" in the sixties, with Austrin, Morris, Wolsely, Riley
etc etc??

The Chinese buy their transformers by the ship-load. An order of
20 pcs for a European winder, is cause for celebration. So costs are
many times higher.


Warranties from Chinese dealers (eBay) are *worthless* - when my volume
pot went tits up the dealer (Edmund Lam, aka 'Zagger1' on Fleabay)
promised a replacement - it never arrived. When I pointed this out to him
after some weeks, he promised to put another in the post - guess
what....??

This is leading to an interesting new development. There is a Swedish amp
builder I know who now offers a five year unconditional warranty, extendable
to ten years for his valve amps (90 days for valves) This is an expression
of confidence in the quality of his product.

There was a whole generation that missed out on thermionic audio.

I almost did. Obviously, radios and record players (stereograms) were
valves when I wuz a kid, but I wasn't taking much notice. Maybe I have/had
deep-seated/ingrained memories of the sound quality and was trying
unsuccessfully to find it with SS gear??

Could be:-) My father was the proud owner of a mono set up in the
fifties, Leak TL12. We used to listen to Schubert. Then I used to sneak
upstairs and play Elvis Presley "All Shook Up" on the Dansette (or
whatever the thing was called)

Nothin' like a bit of culture on a Sunday:-)

Iain

The things you see when ya go lookin'......
 

"Andre Jute" wrote in message
oups.com...

Keith G wrote:
OK, but I gotta say my (possible) future amp plans would probably be more
along the lines of a top-flight 300B with '****-off' iron.....

(Not only is that on the back burner, but the cooker ain't even switched
on!!)

Keith:

Given on the assumption that by "'****-off' iron" you mean the very
best transformers, regardless of price:


No, not *regardless* of price - 'quality' within reasonable limits, but not
'budget iron' like Hammond....



Ever hear of the concept in economics of marginality? Technically it is
used to determine at which price per unit a perfect market clears. But
on the ground, and in core theory, it depends on the perception of
individuals about which products are worth more money because they give
greater satisfaction than the possession of the money. A corollary is
that greater and greater amounts of money at each step buy lesser and
lesser *increases* in satisfaction.


Well aware of that - it's commonly called the Law Of Diminishing Returns.

It is the very reason I tried the Chinese SETs - I guessed they would
represent excellent VFM (they do) and would not be too far behind the 'best'
(which I have yet to hear for myself) and would give me an idea without
spending a fortune on what might have been a Fool's Errand....



Your dream on the backburner is on the face of it not a bad idea.


On the back burner of an oven which is *not* even switched on remember - I
have just funded another computer build and will probably build one for
myself before I even think about more amps. 'Much later in the year (if this
year at all)' is the programme I have in mind...


For
instance, many of us own absolutely better tube amps than you do, and
in a large number of cases we can afford them only because we built
them ourselves. We consider the expenditure worthwhile, and the
pleasure of something of (often) our own design and construction adds
to the value perceived. However, you should not fall into the trap of
thinking that the difference between your cheap Chinese and our cheap
DIY at several times the price of cheap Chinese is a gulf the size of
the Grand Canyon. It is a marginal, incremental difference. Think about
it: you have already arrived in the top one half of one percent of
hi-fi; at this level of hi-fi, all margins are minutely incremental and
very expensive.


Well aware, once again - see above. Don't forget my first SET was the 2A3 I
built with parts from 'Fekki Norsum' which is described thus, in performance
(as, indeed, all his stuff is...). It is very nice and SET me on the road,
but the Chinese amps are just about as good which makes me very wary of
'hype'.......



We would find it a hardship to listen to your cheap chinese rather than
our cheap DIY. That is because we are used to what we have now and,
important this, have paid for it already and justified the cost to
ourselves.

You, having accustomed yourself to the cheap Chinese, and justified it
many times over, may be disappointed after paying several times the
cost of the cheap Chinese to discover that for so much money you have
gained only a small improvement in your sound.


Er, OK - got that *once again*....



At that, you will be in a better position than someone who has to lash
out ten times the price of the cheap Chinese to buy a good European or
American or Japanese tube amp on the open market. The difference will
come not only from the saved money but from the intrinsic DIY
satisfaction, which shines through your posts.


Yes, although the 'DIY satisfaction' is actually higher with the speakers
than it is with what amps I have built, for some reason....??

(Bigger, more immediately discernable differences possibly...??)



None of this will stop you if you really intend to go ahead.


Sure.


*****

When you do go ahead, here's a tip. If you really want "****-you iron",
give the boutique hypesters a miss and buy your iron by the pound.
Literally. I mean it. The best transformer designers and builders earn
most of their basic bread, and a good bit of their jam, from the
national broadcasters. In essence, they give you their expertise for
free because the broadcasters have paid for skill development and
product development.


OK.


snip interesting notes on trannies


having your transformers on display. Many of the highest-profile DIY
tube amp designers in the world swear by Lundahl transformers.


Yes indeed, that's one make that keeps cropping up - and the Sowters that I
see Iain has already mentioned. The interesting thing is there is apparently
a transformer manufacturer just down the road from here (used to supply WAD,
apparently). I don't know who it is or what they do, but come the time I
would make an effort to seek them out....??

Anyway, Jootius Frootius I appreciate your input - it was very interesting.
(Your posts invariably are when you are not showing off, crossposted to the
usual pillocks who have got nothing better to do than rake over the same
boring old ****, ad *nauseatissimo*.....!! ;-)

The things you see when ya go lookin'......
 

"Iain Churches" wrote in message
...

"Stewart Pinkerton" wrote in message
...
On 23 Feb 2006 07:37:16 -0800, "Andre Jute" wrote:


While I would generally hesitate to agree with Jute, he is in this
case quite right. If you really must build a valve amplifier, then the
Lundahl range of transformers does indeed provide excellent
performance at realistic prices. This allows you to go for a more
optimised design than might otherwise be possible, particularly if for
some reason you decide to go down the technically crippled
single-ended route, with its horrific implications regarding core
saturation. Ya need seriously gang-banging iron for those suckers!

Basically, always buy a trannie that will handle a little more power
than you are designing for, rather than a little less. Your bottom end
will be eternally grateful...................
--

Keith has a good alternative to Lundahl, and practically on his doorstep.
- AE Sowter Ltd.


Yes. A definite contender for a *killer amp*....

The things you see when ya go lookin'......
 

Andre - I don't know if you are interested but I have five new SV811-10
which I don't know what to do with.

But these two digit DHTs - they really are DIFFERENT! Yes, a 6SN7
sounds good, but only until you try a 2C22/7193. Then the 1626 is a
real rock and roll tube - great bass dynamics and boogie factor - I
still regret taking it out of my line stage. But the 26 has so much to
offer, it's on another level of sophistication altogether. All this
leaves the 9 pins in the dust. I ahven't tried the single triodes like
Andre says - stuff like the 5842, though I have some. The two small
tubes I like are the ECC40 and E80CC bit these are eclipsed by octals
and in particular the UX bases.

The things you see when ya go lookin'......
 

"Iain Churches" wrote in message
...

"Keith G" wrote in message
...

"Iain Churches" wrote in message
...


G'd evening Keith!


It'll be 'Good Morning' when you see this! (Ran out of time earlier on!!)




I have just come back from a pleasant few hours fettling in my den of
excellence. A CCS cathode follower is bubbling nicely on the front
burner:-)


:-)


Yes, this is fundamental. A better, more *pleasing* sound is what it's
all
about AFAIAC....

Yes. My pal Peter Lewis used to call it the M (musicality) factor.
Peter was a design engineer at Leevers Rich, in the UK. He was a "real"
(not just an NG armchair) engineer, in that he was constantly building
and trying out something. He made a very good living even after
retirement
building bespoke valve amps for discerning clients. He could offer the
features and attention to detail which no larger maker can offer.


Sure a 'one man band' can offer a truly bespoke service!!



It needs to be clearly stated that not everyone will like the SET/Horn
combination - I do, but then then I'm not overly endowed with the
*technical knowledge* that makes this 'difficult' for some people...!!
;-)

Hmm. Once the technical performance has been assessed,
and we know what the amp can (or cannot) do, why not sit back and
enjoy what it has to offer?


??

That's exactly what I do do!!

(Doodoo? :-)



If valve amps are simply too expensive for impoverished/curious types,
they will never join the growing legions of 'thermionophiles'. I'm fairly
sure, that once they have got their feet wet, they will be curious about
'better amps' and, now that valves are almost parallel with SS stuff on
prices, a clear upgrade path becomes visible presenting some interesting
options.

Yes. Interesting point. My dealer pal tells me that he can offer an
entry level valve amp for about the same money as a mid price SS system.
From then on, the only way is up :-)


OK, hate to say it, but there valve amps from 80 quid up (at times) on
eBay - yes, I know they ain't going to be Ongakus at that money but I would
bet they sound just as good (in a valvey way) as all the 99 quid Richer
Sounds SS offerings!

Again, I say it's the 'foot on the first rung'!!

(You have said yourself that people rarely (ever?) migrate *from*
valves...!! ;-)


Patrick is very smart.


Yes, I seen a pic of him - looks like the President of a Rowing Club!! :-)


He keeps his outfit small, and offers a very good
build and repair service. He has an enviable reputation, and customers
recommend him to others, and keep coming back. His amplifiers are
excellent examples of "tube-craft". He is a very nice guy too, and always
ready with help and advice when asked.


I have heard nothing but the finest words for him....



Either way, valve amp builders will have to do more to convince the
buying
public that they are offering superior quality now that they are up
against stiff competition - it's possibly harsh and will probably weed
out
out a few of the weaker players, but it's for the good of all,
ultimately!!

Yes agreed. The problem is one of volume. I am told that there are
ten different brands of Chinese/Taiwanese/Thai amps all almost identical
and built in the same factory. Isn't that what British Leyland used to
call
"badge engineering" in the sixties, with Austrin, Morris, Wolsely, Riley
etc etc??


Interesting. I have seen no evidence of 'badge engineering' by the Chinese
themselves, but I believe some of the stuff offered by one of the English
importers is rebadged Ming Da...???



The Chinese buy their transformers by the ship-load.


Sure, if they are producing shiploads of amps they would need to, wouldn't
they??


An order of
20 pcs for a European winder, is cause for celebration. So costs are
many times higher.


There is more to higher costs in this country than sheer 'economies of
scale'....


This is leading to an interesting new development. There is a Swedish amp
builder I know who now offers a five year unconditional warranty,
extendable
to ten years for his valve amps (90 days for valves) This is an
expression
of confidence in the quality of his product.


Of course, but no warranty ever comes FOC....


I almost did. Obviously, radios and record players (stereograms) were
valves when I wuz a kid, but I wasn't taking much notice. Maybe I
have/had
deep-seated/ingrained memories of the sound quality and was trying
unsuccessfully to find it with SS gear??

Could be:-) My father was the proud owner of a mono set up in the
fifties, Leak TL12. We used to listen to Schubert. Then I used to sneak
upstairs and play Elvis Presley "All Shook Up" on the Dansette (or
whatever the thing was called)

Nothin' like a bit of culture on a Sunday:-)



Sing Something Simple? :-)

Go check this page out if you want a nice 'wallow'!!

http://www.whirligig-tv.co.uk/radio/musicprog.htm


:-)

The things you see when ya go lookin'......
 

"Stewart Pinkerton" wrote:

While I would generally hesitate to agree with Jute, he is in this
case quite right.

A broken clock is right twice a day.

The things you see when ya go lookin'......
 

Andy Evans wrote:
Andre - I don't know if you are interested but I have five new SV811-10
which I don't know what to do with.

Thanks for the offer, Andy, but I doubt I'll be building more kilovolt
amps -- not scared, just wondering if I want to risk my back to pick up
an amp which weights nearly as much as I do. On the other hand, whoever
buys or inherits my Millennium will probably have to use 811s in the
place of the unobtanium SV-572-xx...

But these two digit DHTs - they really are DIFFERENT! Yes, a 6SN7
sounds good, but only until you try a 2C22/7193.

Was ist das?

Then the 1626 is a
real rock and roll tube - great bass dynamics and boogie factor -

I think Bob Danielak built a car amp with them. Can't remember the
details now, but it fitted on a shelf behind seat of his Fiat X1/9 or
124 Spyder, something like that. I remember he said the difficult thing
was the power supply design and construction.

I
still regret taking it out of my line stage. But the 26 has so much to
offer, it's on another level of sophistication altogether. All this
leaves the 9 pins in the dust. I ahven't tried the single triodes like
Andre says - stuff like the 5842, though I have some. The two small
tubes I like are the ECC40 and E80CC bit these are eclipsed by octals
and in particular the UX bases.

Andre Jute

The things you see when ya go lookin'......
 

Andy Evans wrote:
But the best price/performance ratio is without a doubt the Cut C-Core
transformers made by Lundahl of Sweden. In blind listening tests we ran
they were chosen over the elite Japanese transformers at many times the
price.

Have you tried O-netics, as used by Gary Pimm, Lynn Olsen, and
incidentally me!

Don't even know what they are. It is years since I last bought any
trannies except Lundahls. I have some others here that I must use
first, and too many amps, so I should really break one down and recycle
the trannies every time I build another amp.

Where did you get the O-netics, were they expensive, what is good about
them?

Lynn was one of the first guys into Lundahl, not too long after me,
when they were a truly obscure Scandinavian brand.

Andre Jute

The things you see when ya go lookin'......
 

"Keith G" wrote in message
...

"Iain Churches" wrote in message
...


Keith has a good alternative to Lundahl, and practically on his doorstep.
- AE Sowter Ltd.


Yes. A definite contender for a *killer amp*....

None better I would say:-)

Keith. When the big days comes, before you make contact with them,
send me an e-mail. I shall be able to save you copious amounts of the
"elusive spondoolicks" :-)

Iain

The things you see when ya go lookin'......
 

"Andre Jute" wrote


I think Bob Danielak built a car amp with them. Can't remember the
details now, but it fitted on a shelf behind seat of his Fiat X1/9 or
124 Spyder, something like that. I remember he said the difficult thing
was the power supply design and construction.


http://www.geocities.com/TimesSquare/1965/caramp.html

The things you see when ya go lookin'......
 

"Iain Churches" wrote in message
...

"Keith G" wrote in message
...

"Iain Churches" wrote in message
...


Keith has a good alternative to Lundahl, and practically on his
doorstep.
- AE Sowter Ltd.


Yes. A definite contender for a *killer amp*....

None better I would say:-)

Keith. When the big days comes, before you make contact with them,
send me an e-mail. I shall be able to save you copious amounts of the
"elusive spondoolicks" :-)


OK, will do! ;-)

The things you see when ya go lookin'......
 

In article , Iain Churches
wrote:

"Serge Auckland" wrote in message
...

Interesting! Did you wind your own transformer? What secondary load
are you driving? I presume it's 10k bridging rather than 600 ohm
terminating.



Wound for me at a local broadcast engineering workshop. (I have friends
in low places:-)

Nominal impedance 10k. 48dB attentuation in 2dB steps. Inductance 80H.

Since I am unfamiliar with the use of such transformers for audio, I'll
risk asking a few simple questions. :-)

Can you explain what you mean by "10k bridging" in the above? Does it refer
to the input load/arrangement?

Under what conditions of use does the system present (?) 10kOhms?

What would be the levels of series resistances, shunt capacitances, etc,
for the above device? You quote '80H' for an inductance, but don't
distinguish the coupled (mutual) value from the uncoupled values.

Slainte,

Jim

--
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Audio Misc http://www.st-and.demon.co.uk/AudioMisc/index.html
Armstrong Audio http://www.st-and.demon.co.uk/Audio/armstrong.html
Barbirolli Soc. http://www.st-and.demon.co.uk/JBSoc/JBSoc.html

The things you see when ya go lookin'......
 

In article , Serge Auckland
wrote:

[snip]

One oddity I've noticed. On the SILK attenuator pages, they say of
conventional resistor attenuators "That's why at high attenuation level
(low signal out, low listening level) the bandwidth of such volume
control is very poor and the bandwidth is not constant over any switch
position."

Can you give the URL for the page? I'm puzzled as I'd expect the maximum
output resistance of a conventional attenuator to occur at about the -6dB
setting, and fall as the output level is reduced below that. i.e. not have
a "poor bandwidth" at low settings, but at relatively high ones.

Is there some reason why the transformer referred to *doesn't* also have a
bandwidth that "is not constant" as the attenuation is altered? If nothing
else, I'd assume that the inductances, capacitances, and resistances, would
all tend to change, and affect the bandwidth...

This is only relevant if using very long high-capacitance cables. If
using cables of normal capacitance, and of normal domestic lengths, it
has no relevance as the bandwidth is already well in excess of the
audio bandwidth. Although I think a multi-tapped transformer as an
attenuator is a bit of overkill, it is a theoretically sound solution
as the output impedance will reduce as the attenuation increases.

Will the input impedance not also tend to change as the o/p tap is changed?

Slainte,

Jim

--
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Audio Misc http://www.st-and.demon.co.uk/AudioMisc/index.html
Armstrong Audio http://www.st-and.demon.co.uk/Audio/armstrong.html
Barbirolli Soc. http://www.st-and.demon.co.uk/JBSoc/JBSoc.html

The things you see when ya go lookin'......
 

But these two digit DHTs - they really are DIFFERENT! Yes, a 6SN7
sounds good, but only until you try a 2C22/7193.

Was ist das?

It's 'half' a 6SN7 - a 6J5GT substitute but with two top caps - grid
and anode. It sounds better than any 6SN7, 6J5 type, even better than a
6P5GT which is very nice or a CV1932. cheap - mostly JAN. Terrific
valve - others have remarked the same thing - smokes 6SN7s.

The things you see when ya go lookin'......
 

Where did you get the O-netics, were they expensive, what is good about

them?

Good value - my 6.6K PP level one were $98 each. Very detailed refined
sound - Lynn Olsen specifically says he preferred them to Lundahl. Made
by Bud Purvine,



Andy

The things you see when ya go lookin'......
 

"Jim Lesurf" wrote in message
...
In article , Iain Churches
wrote:

"Serge Auckland" wrote in message
...

Interesting! Did you wind your own transformer? What secondary load
are you driving? I presume it's 10k bridging rather than 600 ohm
terminating.



Wound for me at a local broadcast engineering workshop. (I have friends
in low places:-)

Nominal impedance 10k. 48dB attentuation in 2dB steps. Inductance 80H.

Since I am unfamiliar with the use of such transformers for audio, I'll
risk asking a few simple questions. :-)

Can you explain what you mean by "10k bridging" in the above? Does it
refer
to the input load/arrangement?

For many years now, pro-audio has abandoned the old 600 ohms terminating
(that is, 600 ohms sending impedance, 600 ohms receiving) for the more
modern very low sending impedance (typically less than 50 ohms) into a high
receiving impedance (typically 10kohms) The 10k impedance is referred to as
"bridging" as it can be put across (bridge) a 600 ohm load without
materially affecting the level. The use of the terms is now something of an
anachronism, but is still retained to indicate a high load impedance, and to
distinguish it from the now rarely used 600 ohm terminating imedance. Before
I get lots of replies from professionals pointing out that 600 ohms is still
used, I agree, it is still used, but exceptionally, when terminating very
long lines. In studio use, it is never (almost never?) used.


Under what conditions of use does the system present (?) 10kOhms?

If a transformer is designed for 10k use, it needs to be presented with a
high load impedance on the secondary. A 10k transformer presented with a
600ohm load will distort at a much lower level than with a 10k load, as the
core saturates.

Conversely, if a transformer is designed for 600 ohm use is used with a 10k
load, it won't saturate or distort, but it could have an undesirable peak in
the treble response, although with a well-designed transformer, this won't
be too serious a problem. Nevertheless, the cousel of perfection is to
terminate transforers with their design impedance.


What would be the levels of series resistances, shunt capacitances, etc,
for the above device? You quote '80H' for an inductance, but don't
distinguish the coupled (mutual) value from the uncoupled values.

This will depend on the specific transformer, so I can't answer this....
Iain?

S.