Building my own valve amp
 

"Andy Evans" wrote in message
oups.com...
If a part of that system (say: The amplifier) has audible faults (as
characterised by
appropriate measurements), then it may be discarded as unsuited for
it's purpose

Audible qualities of amplifiers are not the same as measurements

**Yes, they are.

- I
know you just refuse to believe this, and this is why it's impossible
to carry out any sensible debate with you.

**It is impossible for you to carry on a debate with me, because I am
correct.


I can introduce you to a number of people - professional engineers,
musicians etc - who consider a number of solid state amps unsuited for
the purpose of long term serious listening because of a graininess
which gets on their nerves.

**All of which can be characterised by measurements.

But of course you won't believe that
either, will you.

**Of course. I've experienced exactly that. You seem to be under the
delusion that two or three measurements are all that is required to define
the sound of an amplifier. The list is longer, much longer, than that. What
I am saying is this: Perform a range of detailed and exhaustive measurements
on an amplifier. The first, most basic ones are frequency response ones,
into appropriate loads (not resistors). If an amplifier fails these
measurements, it is rejected. Then move on to more complex measurements. At
each point, an amplifier is assessed for audible performance flaws and, if
necessary, it is rejected.

NB: I am not suggesting, for instance, that an amplifier needs to possess
0.00000001% THD or anything like that. Something around 0.1% is probably
adequately low enough. As long as that figure can be maintained at all audio
frequencies, all levels and when driving the specified load impedance (not
resistance).

Trevor Wilson

Building my own valve amp
 

"Andre Jute" wrote in message
oups.com...
On Nov 5, 3:47 pm, "Iain Churches" wrote:
"Trevor Wilson" wrote in message

...

"Keith G" wrote in message
...

"Trevor Wilson" wrote in message
...

"Keith G" wrote in message
...

"Trevor Wilson" wrote

a tidy up

**You are, of course, incorrect. That won't stop you from lying and
misrepresenting my position, nor my words in the future, however.
You've made it into something of an art form. You are a lying piece
of
****.

Iain needs to gauge better how to play you without breaking the
line....

**Not lying would be an excellent start. An ability he clearly lacks.

And you need to gauge better the company here - I don't think there's
a
single regular here that bothers to post *lies*, Trevor...

(I though all that 'lying POS' claptrap had gone South with
Pinky...??)

**Iain lied to and about Stuart too? Hardly surprising. Iain is
incapable
of telling the truth.

Trevor. No cigar for English comprehension:-(

What Keith is saying is that the kind of invective you are now using
was Pinky's trademark, and disappeared (went South) when he did.

Iain

Trevor has a most novel view of what constitutes a lie. He accused me
of lying about j-fets in a debate about negative feedback. When I
protested that I had said nothing whatsoever about j-fets, Trevor
replied that I was "lying by not presenting their advantages over
tubes" [paraphrased]. I was stunned into silence...

**Bull****. However, feell free to provide a cite for your little story.

Trevor Wilson

Building my own valve amp
 

"Keith G" wrote in message
...

"Trevor Wilson" wrote in message
...

"Keith G" wrote in message
...

"Trevor Wilson" wrote in message
...

"Keith G" wrote in message
...


**I'll try to make it REAL simple for you:

If you can't hear it, don't buy it.


That's eBay ****ed then....

**Wrong. There are a great many products available on eBay that
are/have been available in other places.

If you can't hear it, don't buy it.


So 'wise', yet so stupid....

**Let me see if I have this straight:

*I* have suggested that listening to a product is helpful when
determining if a product is worth buying.


No. You have said "If you can't hear it, don't buy it." (see right
above) - that is considerably more emphatic than merely 'helpful'....

**Indeed. Thanks for the correction.



*You* are suggesting that buying first, makes more sense.


News to me - I'm simply suggestiong that sometimes 'buying (or building)
first' is unavoidable in practical terms...

**Nope. It is never unavoidable. If you can't hear it, don't buy it. Buy
something else.




*I* am suggesting that people who sell stuff will always say that it
sounds good.


OK. My experience is different - even the local robber baron will only
describe cheap, plank turntables as 'OK for just making a bit of noise',
but there ya go....

**I'll betcha he says that they're the best value for money turntables,
though.



*You* are suggesting that people selling stuff should always be trusted.


I am? Where is this all coming from? Do you hear voices?

**You are suggesting that people should buy stuff without first performing a
careful evaluation. To do so, implies that the seller is trustworthy.



*I* am suggesting that people who build stuff cannot provide unbiased
advice.


OK.


*You* are suggesting that people who build stuff are absolutely reliable
when offering advice about the stuff they've built.


I am? (More voices?)

**Nope.




Is that about it?

And you call me "stupid".


You bring it on yourself.

**Because I suggest that people listen to a piece of audio equipment, BEFORE
they plonk their cash down? How curious.




Wake up and smell the coffee.


Don't need to.

**Yeah, you do.


In an ideal world to 'hear before you buy' would be the best way to go for
sure,

**Good. I'm pleased we have established that.

but we're not in an ideal world and, for one reason or
another, I suspect the *majority* of audio gear that is bought in this
country is actually bought *unheard*.

**Let's refine that statement to:

"I suspect the *majority* of 'high quality' audio gear that is bought in
this country is actually bought *unheard*."

Is that better?

I made the correction, because a lot of cheap, crappy audio equipment is
probably purcahsed without first being carefully evaluated. OTOH, IME, high
quality audio equipment is carefully listened to before purchase.


In fact, I suspect almost
everybody in this group will have bought stuff at some point either on
spec. or because it was recommended verbally, or even because they read a
favourable review in a magazine!

**SOME, yes. MOST, no. Of course, Poms are different to Aussies. But, I
suspect, not that different.


(It might help you to know that valve amps are not plentiful in 'audio
shops' in this country, contrary to what the strong valve presence in this
group and the current 'valve fad' in audio magazines might lead you
believe - to assemble a selection of valve amps for 'auditioning' would be
a difficult and time-consuming thing...)

**Iain has stated that valve amps constitute the vast majority of high end
amplifier sold in his country. Of course, he can't provide any actual proof
of that. I can tell you that it is easy enough to locate a bunch of valve
amps (in one location) here in Australia. I would expect that it is easier
in the UK. What, with all that crappy weather and all.

Trevor Wilson

Game, SET and match....
 

It just makes the point of what you *like* to hear. Nothing wrong in
that provided you understand it.

I think we understand quite well that we prioritise reproduction we
"like" over reproduction we don't like. What I don't see is why you
talk down this approach as if "we don't know any better" - which we
would if we understood measurements. We've been down this path several
times.

Building my own valve amp
 

**It is impossible for you to carry on a debate with me, because I am
correct.

I'm sorry, at this point I just dissolved into helpless laughter. This
is like a scene out of a bad James Bond movie. Can't you just see the
villain, prosthetic metal hand and diamond tooth, facing James Bond
tied up in a chair by a Bond girl, spitting out these lines as his
voice ends in a half swallowed shriek.

Building my own valve amp
 

Perform a range of detailed and exhaustive measurements
on an amplifier

Could you give us an example of an "exhaustive measurement" which
measures EVERYTHING?

And could you follow that by explaining why, after carrying out such
an "exhaustive test" which by definition needs no further information,
you then need to go on and listen to the amplifier?

Building my own valve amp
 

The word "better" is the problem. It is an objective term that is
being hijacked into a subjective meaning. It has clear objective
meanings in terms of flatness of frequency response, absence of
distortion etc. Can't we simply refer to preference and thus have no
reason to argue?

Well, no. Not really. I can't see that the phrase "sounds better"
hijacks any word that has a specific scientific meaning. It's common
speech.

And your proposal that listeners who are quite secure in their audible
preferences should demote themselves to "subjective", leaving those
who put their trust in some far from exhaustive measurements occupying
the high ground of "objective" continues to be demeaning to those who
have heavily researched hi-fi systems and who know very well the sound
of live instruments.

We can't get away from the situation that we're dealing with sound
here, and all we're doing right now is writing about it, not even
listening to it. Like dancing about architecture really.

Building my own valve amp
 

The fact that amplifiers have reached a state of
essential perfection

Says who? Can you prove this? It's a huge claim, given that amplifiers
for the most part sound different from each other.

Building my own valve amp
 

On Mon, 05 Nov 2007 21:49:27 -0000, Andy Evans
wrote:

The word "better" is the problem. It is an objective term that is
being hijacked into a subjective meaning. It has clear objective
meanings in terms of flatness of frequency response, absence of
distortion etc. Can't we simply refer to preference and thus have no
reason to argue?

Well, no. Not really. I can't see that the phrase "sounds better"
hijacks any word that has a specific scientific meaning. It's common
speech.

No, don't do that. What we are seeking is something that would address
"Is it a better amplifier". See the problem?

And your proposal that listeners who are quite secure in their audible
preferences should demote themselves to "subjective", leaving those
who put their trust in some far from exhaustive measurements occupying
the high ground of "objective" continues to be demeaning to those who
have heavily researched hi-fi systems and who know very well the sound
of live instruments.

We can't get away from the situation that we're dealing with sound
here, and all we're doing right now is writing about it, not even
listening to it. Like dancing about architecture really.


Quoting others doesn't help either. The question really boils down to
this; do you want to listen to something that resembles what the
artist intended, or the output of an effects box?

Oh, and I'm listening as I type,

d

--
Pearce Consulting
http://www.pearce.uk.com

Building my own valve amp
 

On Mon, 05 Nov 2007 21:53:07 -0000, Andy Evans
wrote:

The fact that amplifiers have reached a state of
essential perfection

Says who? Can you prove this? It's a huge claim, given that amplifiers
for the most part sound different from each other.

No, they don't. Apart of course from amplifiers that are designed to
be wrong. You will find these at the "high end", typically.

I am assuming a basic level of competence in my statement.

d

--
Pearce Consulting
http://www.pearce.uk.com