Valve amp (preferably DIY) to drive apair of Wharfedale Diamond II's
 

"Tat Chan" wrote in message
...
Eiron wrote:

Ian Molton wrote:

No amp should be run into distortion for HiFi use. Trouble is that most
valve amps distort within their normal operating conditions.


Technology moves on.
In 50 years we have gone from state-of-the-art valve amps
that sound like "a straight wire with gain"
and don't have any "valve sound"
to today's abominations that are deliberately non-linear.


If there is a market for "valve sound", they will build it ...



Oh, there *is* a market and they *are* building for it. The question you
should be asking is 'why'.....???



(or maybe there are more audiophools with money to throw around looking
for "inner detail" and "character" missing from a wire with gain)


Or less 'engineers' around with their 50,000 different flavours of ss
amplification all secretly thinking that they had got a 'straight wire with
gain'.....

Valve amp (preferably DIY) to drive apair of Wharfedale Diamond II's
 

"Mike Gilmour" wrote


Smell? - Ooh, now yer asking! (Smells like it *has* been ****ting on ss
amps!! ;-) OK, they do have a bit of funny 'factory pong' for an hour or
two but it does burn off!!




Expect thats the new bottles giving out the smell, had the same thing
happen here when I installed 8 new KT88's..the stink was 'orrible but it
went away after about an hour.


Not quite because there's a fairly distinctive niff to them even before
they're fired up......


Funny that, because it's the first time I had quite that strong smell from
new power valves...probably a bit of burnt bean sauce and rice wine after
the factory lunch break :-) ......If they have one that is!


Yes, I must say that having seen a pic or two of great long lines of
assembly workers (or 'thermionic engineers' as we like to call them) I've
been wondering about the conditions myself.....

Valve amp (preferably DIY) to drive apair of Wharfedale Diamond II's
 

"Trevor Wilson" wrote in message
...

"mick" wrote in message
.. .
On Thu, 11 Nov 2004 21:36:58 +0000, Trevor Wilson wrote:

snip

THD is meanongless in the real world. It is a great method of producing
comparisons between amps, but there are so many other factors to be
taken into consideration that, below something like 5%, it is
completely
inaudible.

**Bull****. Way back when I was a trainee tech, some of us experimented
with some pretty crappy speakers and discovered than 1% THD was audible.
Other experimenters have suggested that around 0.1% is a reasonable
threshold for average listeners. Critical listeners may be able to
detect
far less.


You can produce two signals with identical THD%.

**Yep.

One will have very
audible distortion and the other won't.

**Yep.

It depends on the relative
strengths of the harmonics.

**And the TOTAL level of those harmonics. Less than around 0.1% is
inaudible, regardless of the harmonic structure. That is why I cited 0.1%
as being a reasonable indicator of 'high fidelity'.

This is reproducible under test conditions by
adding harmonics to a pure tone.

**Yep. Been there, done that. Anything less than around 1% is pretty hard
to hear.

The signal with the higher level of low,
even harmonics will sound purer. In the light of this, how can you state
that comparison of THD is meaningful *in listening tests*?

**Er, because THD figures of more than 0.1% are audible, under careful
conditions. And figures of less than 0.1% are pretty much inaudible, under
careful conditions. What part of this, don't you understand?

For amp
designing and comparison measurements, yes, but not for listening.

**Wrong. If distortion is audible (ie: 0.1%), then it may well be
audible.

Your
listener will quickly pick up on, say, third harmonic if the second
harmonic is at a low level but as the second harmonic level increases it
masks the third harmonic problem. The THD goes up but the sound appears
"purer" to the listener.

**Then it is time to choose a new listener. Or are you speaking of THD
figures which are greater than 0.1%?

Obviously, I am talking about test tones here,
not real music, but that tends to introduce other masking effects anyway,
as the relative values of the harmonics are detected differently at
different frequencies. By all means design for low THD as this affects
the entire system, but a high THD does not necessarily mean that the amp
sounds bad or that the effect of the high THD is audible.

**I never suggested otherwise. HOWEVER, there is little point in bothering
with an amp, which does not meet some basic criteria. THD figures of less
than around 0.1% are necesseary to ensure inaudibility to a critical
listener.


A very interesting debate and difficult to snip.

My question is why is it that, in here, there's a few who constantly run
around screaming about 'distortion' like someone who's just been gang-banged
by the crew of a Russian trawler (or, perhaps, more likely because they
*haven't* been.... ;-) and then you ask someone *long in the trade* of
designing and building amps and they just smile?

And I just *know* the 'Zen' boys out in the Far East (where 'valves with
everything' rules**) would give you one of those looks which can't be
scruted....?? :-)

Other than 'signal breakup' when the volume's wicked up too hard in certain
circumstamces, what TF does this 'distortion' actually sound like?? What
should I be looking for?? Perhaps if I knew what it was I could develop a
loathing for it also.....??? :-)

(Now, why do I also know that I'm not going to get an answer to this that
doesn't sound like it's coming from a raving looney?)



**see these screenshots from the recent film 'Infernal Affairs' (2002)

http://www.apah69.dsl.pipex.com/keit...laffairs01.jpg

http://www.apah69.dsl.pipex.com/keit...laffairs02.jpg

Valve amp (preferably DIY) to drive apair of Wharfedale DiamondII's
 

Keith G wrote:


You asked a question why some people didn't accept your view. I attempted
to answer with my opinion as to why some people could not accept your
view, Your answer to my reply was to repeat the same question again, this
time describing my reply as "bull****" maybe you should read the reply, or
maybe you are just not taking notice.

Its seems to heve been summed up in another post that just went by, I
quote...

"Yes, agreed - I think there's too much 'you express your opinion in my
terms and I will allow it' tried on in here, at times.

Needs to be remembered that 'ultimate communication failure' (real or
imagined) with certain parties in this ng isn't of any particular
consequence...."

Just a point about your comment about "percieved accuracy". I assume you
are sitting in front of a monitor reading this, and that monitor will be
displaying white areas. Now the white light you see outside from the sun
is composed of all frequences, the light from the monitor is only composed
of three frequencies. We percieve them both to be white, we can all agree
on the colour from the monitor being white. Which can be accuratly
described as white ? Does it matter if they are both percieved the same,
even though they can be measured and shown to be very different?




Nick, excellent points well made.

(I admire your patience with these 'Valve Envy' clowns.... :-)


Keith, as you know, I don't give a toss what people think or say on the
subject, I only try and add something when I think it has some
relevence. Not a case of patience, I just don't worry that much about it
all that much.

--
Nick

Valve amp (preferably DIY) to drive apair of Wharfedale DiamondII's
 

Ian Molton wrote:
Nick Gorham wrote:

Firstly, could you learn to snip usenet posts? it makes it far easier to
find the relevant text.


If you took a moment of your time to noitice that I had snipped all the
text that didn't relate directly to my reply, you may even get to read
it in the first place.

I try to assume others may be reading the post, and may not want to take
the trouble of checking the previous ones, so try and include enough to
make the post self explanitory, without altering the point or content of
said post.

You asked a question why some people didn't accept your view. I
attempted to answer with my opinion as to why some people could not
accept your view, Your answer to my reply was to repeat the same
question again,


Because you failed to answer it, and, in true 'valvie' form, went off on
an irrelevant, poorly described, innacurate tangent.

Just because you choose to dislike the answer, didn't mean I didn't
attempt to answer it, don't ascribe your opinions on my actions, thank you.


this time describing my reply as "bull****" maybe you

should read the reply, or maybe you are just not taking notice.


Dont write bull**** and I wont need to call it such...


Ah, so now you are the official keeper of the bull**** stamp ? You have
a numerically perfect bull**** detector about your person ?

Just a point about your comment about "percieved accuracy". I assume
you are sitting in front of a monitor reading this, and that monitor
will be displaying white areas. Now the white light you see outside
from the sun is composed of all frequences, the light from the monitor
is only composed of three frequencies. We percieve them both to be
white, we can all agree on the colour from the monitor being white.
Which can be accuratly described as white ? Does it matter if they are
both percieved the same, even though they can be measured and shown to
be very different?


The light from the sun is closest to true white, being composed of
nominally even levels of the full spectrum of visible light.

Yes, I said that, why are you repeating what I said in such a way to
make it sound as if you are correcting me by just repeating?


there exists a real definition for white light. there is no such
definition for the synthesised 'white' light produced in CRTs. no two
are alike.

Yes, I said that, why are you repeating what I said in such a way to
make it sound as if you are correcting me by just repeating?


In terms of perception, yes, they are both 'white' (to me). In terms of
accuracy, sunlight is way closer.

That was my exact point, in terms of your perception (and AFAIK everyone
else's) they are the same, so only a pedant would not describe the
light from a CRT as white, and the accuracy of that white-ness can be
measured and described in terms of a colour temperature, which only has
real meaning for a hot body emmiting a continuious spectra. So the
accuracy of the whitenes from a CRT can be measured and discussed,
whereas its not actually white at all. Hence the example of "percieved
accuracy".

--
Nick

Valve amp (preferably DIY) to drive apair of Wharfedale DiamondII's
 

Tat Chan wrote:


Hmmm ... maybe the Yanks trust the Brits in defence related matters.

Or maybe at that time they assumed they were immune to such things...

Having said that I worked on presses for EFA as well with no more
hassle. Actually now I think back, I think I did sogn some form to allow
a background check. Bugger, must mean I am not a threat to the Nation :-(

--
Nick

Valve amp (preferably DIY) to drive apair of Wharfedale Diamond II's
 

On 14 Nov 2004 20:21:57 GMT, ohawker (Andy
Evans) wrote:

He'd spent $3,000 on SS pre amd power amps, but after a year he could stand it
no longer, and went to all tubes, how's that for 22 yr old ears?

Probably just a sign of youthful ignorance and love of quirky toys. As
he gains experience, he'll most likely go back to SS.
--

Stewart Pinkerton | Music is Art - Audio is Engineering

Valve amp (preferably DIY) to drive apair of Wharfedale Diamond II's
 

On Sun, 14 Nov 2004 20:41:39 +0000, Rob
wrote:

Stewart Pinkerton wrote:

We *do* listen, it seems to be your side that seems to need some kind
of bull**** justification for what is clearly a personal preference
for euphonic distortion, as opposed to the unalloyed sound of the
master tape.

I know that you have, and I respect your opinion based on listening -
you've done more than most (including me) to clarify things in your own
mind. My 'bull****' is no more or less than preference - if you think
that arises from distortion, then that's up to you.

I don't 'think' it arises from distortion, I can *demonstrate* that it
does, by comparing the sound of your preferred amplifier to one that
demonstrably does *not* alter the input signal in any audible way.
--

Stewart Pinkerton | Music is Art - Audio is Engineering

Valve amp (preferably DIY) to drive apair of Wharfedale Diamond II's
 

On Sun, 14 Nov 2004 23:02:06 +0000, Nick Gorham
wrote:

Ian Molton wrote:


Why cant you accept that valve amps (non transparent ones) simply
distort in a way you like, and (good) SS (or valve) amps do not distort
audibly.


Because, whilst I don't think anyone is claming that valve amps produce
less measurable alteration of the signal than solid state ones, I think
everyone who is trying to make the same point, is saying that it seems
to them that the valve amp appears to reproduce music in a more accurate
fashion, not measurable accuracy, but percieved accuracy. And because of
the perceived increase in accuracy, I think that people find the use of
the word distortion problematic. It is hard to use a term that you have
attached negative connatations to, to describe a effect that they see as
positive.

Step back from this for a minute and think about it, there have been a
steady procession of posters saying almost the same thing about why they
like valve amps, and what they percieve the difference in sound to be.
There seems to be a high correlation between their description of the
sound, and what it is that they feel is lacking in solid state
amplification. This to me is showing that there may well be something
real at work here, something that should deserve closer study.

While on the "other" side, there is a monotone of comments along the
lines of "nothing to see here, move on". No audible distortion, For all
intents perfect. All sound the same, etc...

I think you miss the point. We older folks who have had extensive
experience of both valve and SS amps over the years, are perfectly
well aware of what some people like abiout valve amps. There is no
'mystery' here, simply a collection of very well-known *euphonic*
artifacts which are most noticeable in single-ended designs, and
hardly exist at all in some high-powered and very high quality designs
such as the ARC VT100. Some of us prefer SS amps, or at least
sonically transparent amps, and we resent valvies telling us that SS
amps produce 'cold, harsh' sound, when what is *really* happening is
that good SS amps reproduce their inputs faithfully, while valve amps
do not, but *add* artifacts which some people prefer.

Hence the kind of comments which you quite rightly ascribe to us
above. In the real world, there *is* no audible distortion in good
modern amps (SS or valve), they *are* to all intents perfect, and
here's the clincher, they *do* all sound the same.

--

Stewart Pinkerton | Music is Art - Audio is Engineering

Valve amp (preferably DIY) to drive apair of Wharfedale Diamond II's
 

On Mon, 15 Nov 2004 14:02:36 +1100, Tat Chan
wrote:

Nick Gorham wrote:

Tat Chan wrote:

Stewart Pinkerton wrote:

I spent the early part of the '80s
working mostly in Arizona with Hughes Aircraft,

wouldn't you have required a security clearance for that, or at the
very least be an American citizen?

No, I didn't have to be an American citizen. I actually worked for
Hughes Microelectronics, which was a division of Hughes Aircraft
Company, and in fact was the only offshore company in the Hughes
empire at the time. I was working on the ARBS bombsight for the
Harrier/AV8B, which was a joint effort between Hughes and Ferranti, so
there were several Brits on site most of the time. The factory was in
fact on the Davis-Monthan US Air Force base in Tucson, so we weren't
allowed to wander off the premises.

The only time we got some flak was when we got fed up with all the
gung-ho crap around the place, and with a large black marker we added
a line to a USMC poster which was stuck up in 'our' office. The poster
bore the classic tag "United States Marine Corps needs a few good
men", to which we added "they sure do!". There was something of a
sense of humour failure when the Yanks saw that.......... :-)

BAE systems over here requires its staff to be citizens.


Maybe not, we did presses for General Dynamics and McAir around that
time, and when we went over for the final commisioning there was no
problem. And that was where they were building (at least F16/18's).

Hmmm ... maybe the Yanks trust the Brits in defence related matters.

To a certain extent, they do, but there were some new product design
meetings on the base that they wouldn't let us attend.

--

Stewart Pinkerton | Music is Art - Audio is Engineering