
October 11th 04, 06:23 AM
posted to uk.rec.audio
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Big Sub
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October 11th 04, 06:25 AM
posted to uk.rec.audio
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Big Sub
On Sun, 10 Oct 2004 23:13:07 +0100, "Keith G"
wrote:
"Stewart Pinkerton" wrote in message
.. .
On Sun, 10 Oct 2004 11:46:01 +0100, "Keith G"
wrote:
"Stewart Pinkerton" wrote in message
...
On Fri, 8 Oct 2004 12:55:59 +0100, "Keith G"
wrote:
Steady on! You'll be building that SET next......!! ;-)
I have never had *any* intention of building a SET amplifier!
Well, there you go - I could have sworn I saw you post 'you were tempted
to
build one yourself' at some point???
(I must be losing it....... ;-)
You probably are - but what I said was that I was considering
designing and building a triode amp. I most certainly did *not* say a
single-ended amp, since they're fundamentally incompetent, and my
point was that it should be possible to build a *good* amp, even when
technically challenged by using valves........
Well, come on then - cut the cackle and get stuck in! Do what new Geoff says
and 'have some fun'! (Who knows, if you build it it, you might even like
it!! ;-)
In any case, you should be able to make a few ackers on it if you didn't
want to keep it - who here could resist a 'Pinky Special'?? Feck, you could
even spray it pink and get a real 'rosy glow'....!! :-)
Busy rebuilding a bedroom right now, so all the hi-fi stuff's on the
back burner. I'll probably do the 'big sub' first, as it will be a
useful addition, rather than just a curious toy.......
--
Stewart Pinkerton | Music is Art - Audio is Engineering
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October 11th 04, 05:50 PM
posted to uk.rec.audio
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Big Sub
In message , Stewart
Pinkerton writes
On Sun, 10 Oct 2004 18:56:20 +0100, Chris Morriss
wrote:
In message , Stewart
Pinkerton writes
what I said was that I was considering
designing and building a triode amp. I most certainly did *not* say a
single-ended amp, since they're fundamentally incompetent, and my
point was that it should be possible to build a *good* amp, even when
technically challenged by using valves........
I was at the National Vintage Communications Fair at the NEC today. One
chap had a pair of 833 triodes for sale at only £10 each. Now if you
were prepared to have the OPTs made (about 12K primary Z at 200mA dc
should do) and you build the 2kV supply then you could have a stereo SE
triode amp to beat the Japanese monsters.
Which part of 'they're fundamentally incompetent' did you fail to
understand?..................
Also, why would one save a few quid by buying those triodes, when a
pair of suitable wideband output trannies would cost the best part of
a grand? That's the *other* reason that SETAs are a bad idea, the
trannies have to be absolutely *huge* because of the high level of DC
current.
I had a look at the anode curves on the Duncanamps site. As far as I
can see, there's no way to get any sort of linearity out of one of them
single ended. A pair in class-B P-P must have made a scary PA amp in
the old days, but certainly not one on its own.
An OPT would cost a fortune, I paid enough to Sowter to have a couple of
SE OPTs custom wound for my DA100 triodes, and they're only 900V at
90mA.
I actually like properly designed SET amps (using proper triodes like
845's or DA100's of course, not weedy little 300Bs), but I would NEVER
claim that they are high fidelity!
--
Chris Morriss
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October 11th 04, 07:08 PM
posted to uk.rec.audio
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Big Sub
An OPT would cost a fortune, I paid enough to Sowter to have a couple of
SE OPTs custom wound for my DA100 triodes, and they're only 900V at
90mA.
They the ones about seven or eight inches high?......
--
Tony Sayer
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October 11th 04, 07:43 PM
posted to uk.rec.audio
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Big Sub
In message , tony sayer
writes
An OPT would cost a fortune, I paid enough to Sowter to have a couple of
SE OPTs custom wound for my DA100 triodes, and they're only 900V at
90mA.
They the ones about seven or eight inches high?......
What the triodes or the transformers :-)
The DA100 is a wonderful looking bottle, about 7" tall. It's one of a
handful of valves with a very strange square 4-pin base. Once you've
seen one you won't fail to recognise another one. They are worth silly
money nowadays. I sold 3 rather rough ones on Ebay a year ago, one had a
broken pin and they still fetched over £500 for the three.
I still have four. Two for the amps, and two as spares.
--
Chris Morriss
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October 11th 04, 08:22 PM
posted to uk.rec.audio
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|
Big Sub
In article , Chris Morriss
writes
In message , tony sayer
writes
An OPT would cost a fortune, I paid enough to Sowter to have a couple of
SE OPTs custom wound for my DA100 triodes, and they're only 900V at
90mA.
They the ones about seven or eight inches high?......
What the triodes or the transformers :-)
The DA100 is a wonderful looking bottle, about 7" tall. It's one of a
handful of valves with a very strange square 4-pin base. Once you've
seen one you won't fail to recognise another one. They are worth silly
money nowadays. I sold 3 rather rough ones on Ebay a year ago, one had a
broken pin and they still fetched over £500 for the three.
Arrrrrrrrrrrrrrrrrrrrrrgggggggggggghhhhhhhhhhhhhhh hhh!!!!!!!!!!!!!!
Threw a load of them out about 6 years ago!. Never thought anyone would
ever need them again!!!...
Moral is never ever throw anything away  (((((((((((((
I still have four. Two for the amps, and two as spares.
--
Tony Sayer
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October 11th 04, 10:16 PM
posted to uk.rec.audio
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|
Big Sub
On Mon, 11 Oct 2004 18:50:04 +0100, Chris Morriss
wrote:
In message , Stewart
Pinkerton writes
On Sun, 10 Oct 2004 18:56:20 +0100, Chris Morriss
wrote:
In message , Stewart
Pinkerton writes
what I said was that I was considering
designing and building a triode amp. I most certainly did *not* say a
single-ended amp, since they're fundamentally incompetent, and my
point was that it should be possible to build a *good* amp, even when
technically challenged by using valves........
I was at the National Vintage Communications Fair at the NEC today. One
chap had a pair of 833 triodes for sale at only £10 each. Now if you
were prepared to have the OPTs made (about 12K primary Z at 200mA dc
should do) and you build the 2kV supply then you could have a stereo SE
triode amp to beat the Japanese monsters.
Which part of 'they're fundamentally incompetent' did you fail to
understand?..................
Also, why would one save a few quid by buying those triodes, when a
pair of suitable wideband output trannies would cost the best part of
a grand? That's the *other* reason that SETAs are a bad idea, the
trannies have to be absolutely *huge* because of the high level of DC
current.
I had a look at the anode curves on the Duncanamps site. As far as I
can see, there's no way to get any sort of linearity out of one of them
single ended. A pair in class-B P-P must have made a scary PA amp in
the old days, but certainly not one on its own.
An OPT would cost a fortune, I paid enough to Sowter to have a couple of
SE OPTs custom wound for my DA100 triodes, and they're only 900V at
90mA.
I actually like properly designed SET amps (using proper triodes like
845's or DA100's of course, not weedy little 300Bs), but I would NEVER
claim that they are high fidelity!
Properly designed SET amp = military intelligence.............
--
Stewart Pinkerton | Music is Art - Audio is Engineering
|

October 12th 04, 01:35 PM
posted to uk.rec.audio
|
|
Big Sub
"Keith G" wrote in message
...
"Stewart Pinkerton" wrote in message
...
On Sun, 10 Oct 2004 11:46:01 +0100, "Keith G"
wrote:
"Stewart Pinkerton" wrote in message
...
On Fri, 8 Oct 2004 12:55:59 +0100, "Keith G"
wrote:
Steady on! You'll be building that SET next......!! ;-)
I have never had *any* intention of building a SET amplifier!
Well, there you go - I could have sworn I saw you post 'you were tempted
to
build one yourself' at some point???
(I must be losing it....... ;-)
You probably are - but what I said was that I was considering
designing and building a triode amp. I most certainly did *not* say a
single-ended amp, since they're fundamentally incompetent, and my
point was that it should be possible to build a *good* amp, even when
technically challenged by using valves........
Well, come on then - cut the cackle and get stuck in! Do what new Geoff
says and 'have some fun'! (Who knows, if you build it it, you might even
like it!! ;-)
In any case, you should be able to make a few ackers on it if you didn't
want to keep it - who here could resist a 'Pinky Special'?? Feck, you
could even spray it pink and get a real 'rosy glow'....!! :-)
Purely Purist Pinketons's Pink Project Proposal? :-)
|

October 12th 04, 01:55 PM
posted to uk.rec.audio
|
|
Big Sub
"Mike Gilmour" wrote in message
...
"Keith G" wrote in message
...
"Stewart Pinkerton" wrote in message
...
On Sun, 10 Oct 2004 11:46:01 +0100, "Keith G"
wrote:
"Stewart Pinkerton" wrote in message
m...
On Fri, 8 Oct 2004 12:55:59 +0100, "Keith G"
wrote:
Steady on! You'll be building that SET next......!! ;-)
I have never had *any* intention of building a SET amplifier!
Well, there you go - I could have sworn I saw you post 'you were tempted
to
build one yourself' at some point???
(I must be losing it....... ;-)
You probably are - but what I said was that I was considering
designing and building a triode amp. I most certainly did *not* say a
single-ended amp, since they're fundamentally incompetent, and my
point was that it should be possible to build a *good* amp, even when
technically challenged by using valves........
Well, come on then - cut the cackle and get stuck in! Do what new Geoff
says and 'have some fun'! (Who knows, if you build it it, you might even
like it!! ;-)
In any case, you should be able to make a few ackers on it if you didn't
want to keep it - who here could resist a 'Pinky Special'?? Feck, you
could even spray it pink and get a real 'rosy glow'....!! :-)
Purely Purist Pinketons's Pink Project Proposal? :-)
Possibly, perhaps *probably*.....!! :-)
|

October 12th 04, 05:39 PM
posted to uk.rec.audio
|
|
Big Sub
In message , Stewart
Pinkerton writes
Properly designed SET amp = military intelligence.............
I mean one where the 'designer' gave at least a cursory look at the
anode curves to work out the optimum load impedance and dc biasing
point!
--
Chris Morriss
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