Bob Latham wrote:

Don't anyone ever tell me all good amps sound the same, they
simply don't, unless of course these amps are both not good.

Or one of them was good and the other wasnt.

Or the listener imagined it (you didnt say anyone else heard that, only
the listener)

All good amps will produce the *exact same* voltage pattern on their
outouts. hence if theres a different sound, at least one of the amps is
'not good'.

You are also unclear on the point of wether any other parts of the
signal path changed - did you use the same source on both amps or not?

"Ian Molton" wrote in message
...
Bob Latham wrote:

Don't anyone ever tell me all good amps sound the same, they
simply don't, unless of course these amps are both not good.

Or one of them was good and the other wasnt.

Or the listener imagined it (you didnt say anyone else heard that, only
the listener)

All good amps will produce the *exact same* voltage pattern on their
outouts. hence if theres a different sound, at least one of the amps is
'not good'.

You are also unclear on the point of wether any other parts of the signal
path changed - did you use the same source on both amps or not?

It would only produce the *exact same* voltage pattern, if it were the
*exact same* amp, good or otherwise.

I must admit that I have never subscribed to the 'golden ear' brigade.
However I have used a Quad 33 as a pre-amp, later replaced with a
Cambridge C70 (A1 without the power amps) and now a NAD 3120 as a
pre-amp only.

I have to say that after getting used to the Quad, when I replaced it
with the Cambridge the sound was totally different - much more solid -
perhaps what some would describe as warmer - and with a noticable loss
of higher frequencies. The Quad by comparison would be described as
polite and laid back with a distinct lack of dynamics. Comparing their
outputs on a network analyser shows them to have a similar frequency
and phase response - certainly nothing that would account for the
audio difference.

The change to the NAD was more subtle but still noticable. Certainly
the top end was more detailed (cymbals and triangles show things up
remarkably well) and the bass was noticably deeper but not so 'in your
face' (I like classical organ music.) Again however the frequency
response and phase responses were almost identical to the other two.

Anyone any polite suggestions as to cause? Even my wife and children
(then teenagers) noticed the difference without asking or prompting.


--
Woody

On Sun, 10 Oct 2004 06:59:39 GMT, "harrogate2"
wrote:

I must admit that I have never subscribed to the 'golden ear' brigade.
However I have used a Quad 33 as a pre-amp, later replaced with a
Cambridge C70 (A1 without the power amps) and now a NAD 3120 as a
pre-amp only.

I have to say that after getting used to the Quad, when I replaced it
with the Cambridge the sound was totally different - much more solid -
perhaps what some would describe as warmer - and with a noticable loss
of higher frequencies. The Quad by comparison would be described as
polite and laid back with a distinct lack of dynamics. Comparing their
outputs on a network analyser shows them to have a similar frequency
and phase response - certainly nothing that would account for the
audio difference.

The change to the NAD was more subtle but still noticable. Certainly
the top end was more detailed (cymbals and triangles show things up
remarkably well) and the bass was noticably deeper but not so 'in your
face' (I like classical organ music.) Again however the frequency
response and phase responses were almost identical to the other two.

Anyone any polite suggestions as to cause? Even my wife and children
(then teenagers) noticed the difference without asking or prompting.

Sure - try it again under level-matched DBT conditions. Been there,
done that many times. Without LMDBT, it don't mean a thing.

--

Stewart Pinkerton | Music is Art - Audio is Engineering

In article , harrogate2
wrote:
I must admit that I have never subscribed to the 'golden ear' brigade.
However I have used a Quad 33 as a pre-amp, later replaced with a
Cambridge C70 (A1 without the power amps) and now a NAD 3120 as a
pre-amp only.

I have to say that after getting used to the Quad, when I replaced it
with the Cambridge the sound was totally different - much more solid -
perhaps what some would describe as warmer - and with a noticable loss
of higher frequencies. The Quad by comparison would be described as
polite and laid back with a distinct lack of dynamics. Comparing their
outputs on a network analyser shows them to have a similar frequency and
phase response - certainly nothing that would account for the audio
difference.

The change to the NAD was more subtle but still noticable. Certainly the
top end was more detailed (cymbals and triangles show things up
remarkably well) and the bass was noticably deeper but not so 'in your
face' (I like classical organ music.) Again however the frequency
response and phase responses were almost identical to the other two.

Anyone any polite suggestions as to cause? Even my wife and children
(then teenagers) noticed the difference without asking or prompting.

My recollection is that the 33 does not have a very flat response even with
the controls set as near flat as possible compared with more modern units.
FWIW my experience is that even quite small changes in overall response can
be audible.

I'd be interested to know how you measured the response in terms of the
circumstances of use. Afraid I don't know much about the other amps you
mention, but wonder about things like the levels of hum/ripple, output
impedances, etc.

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 other explanation is that the device you used for comparing the
frequency response and phase responses was not sufficiently resolving to see
the differences. I note you say almost identical so there was a difference
?
I note Stewart has pointed out that you cannot test without LMDBT. It is
most important that levels are exactly matched but I do not agree on the
merits of DBT. From memory Stewart has a Krell amp, if all "good" amps
sound the same does he think that it is not until you get to Krell territory
that amps sound "good" or was it their robust build quality that justified
the additional outlay ?
Regards Richard
"harrogate2" wrote in message
...
I must admit that I have never subscribed to the 'golden ear' brigade.
However I have used a Quad 33 as a pre-amp, later replaced with a
Cambridge C70 (A1 without the power amps) and now a NAD 3120 as a
pre-amp only.

I have to say that after getting used to the Quad, when I replaced it
with the Cambridge the sound was totally different - much more solid -
perhaps what some would describe as warmer - and with a noticable loss
of higher frequencies. The Quad by comparison would be described as
polite and laid back with a distinct lack of dynamics. Comparing their
outputs on a network analyser shows them to have a similar frequency
and phase response - certainly nothing that would account for the
audio difference.

The change to the NAD was more subtle but still noticable. Certainly
the top end was more detailed (cymbals and triangles show things up
remarkably well) and the bass was noticably deeper but not so 'in your
face' (I like classical organ music.) Again however the frequency
response and phase responses were almost identical to the other two.

Anyone any polite suggestions as to cause? Even my wife and children
(then teenagers) noticed the difference without asking or prompting.


--
Woody

Just Askin' wrote:

It would only produce the *exact same* voltage pattern, if it were the
*exact same* amp, good or otherwise.

Yeah, and we all know you've got the mysterious Vorlon electron
recyclign machine in your back garden so that you can repeat the test
with the same electrons.

Muppet.

Richard Wall wrote:
The other explanation is that the device you used for comparing the
frequency response and phase responses was not sufficiently resolving to see
the differences. I note you say almost identical so there was a difference
?
I note Stewart has pointed out that you cannot test without LMDBT. It is
most important that levels are exactly matched but I do not agree on the
merits of DBT.

I dont see how you can fail to agree on the merits of DBT - it removes
both the testers AND the subjects bias.

"harrogate2" wrote in message
...
I must admit that I have never subscribed to the 'golden ear' brigade.


Believe it - they exist. I once asked my partner (musician) to stop me when
I had increased the sound from a Technics deck (with pitch sliders) by a
semitone by 'blind' listening alone - she stopped me at virtually *dead on*
+ 6%!! (On many other occasions she has been able point out subtle
differences in sounds that I hadn't heard up 'til then but which became
immediately obvious.....)

Me? - I've no idea and never trust my own hearing beyond 'liking/preferring'
or 'not liking/not preferring' a sound. Which is why I often quote the
remarks of others who claim (and seem) to have better 'listening' abilities.
Much as some here don't want to hear it, I only decide on 'improvements' (or
otherwise) over an extended listening period with a range of very familiar
music. But then I go a long way matching components to produce a similar
'house' sound anyway and will only say that, AFAIAC, an amp is only one half
of the vital and inseparable amp/speakers combination in any given listening
room, in any case...


snip

The change to the NAD was more subtle but still noticable. Certainly
the top end was more detailed (cymbals and triangles show things up
remarkably well) and the bass was noticably deeper but not so 'in your
face' (I like classical organ music.) Again however the frequency
response and phase responses were almost identical to the other two.

Anyone any polite suggestions as to cause? Even my wife and children
(then teenagers) noticed the difference without asking or prompting.


Well if the 'all good amps sound the same' mantra is true (a good example of
the 'banging on' we hear so much about...) it kinda infers that at least one
of your amps isn't too good, doesn't it? Also that manufacturers using
different components, circuit topologies and architecture must, for the
greater part, be simply ****ing in the breeze if all they do is achieve
another version of exactly the same sound...??

To me it's quite simple - I definitely hear no difference between SS amps
from, say, £150 and up other than sheer volume, but I don't think any two
different valve amps will sound exactly the same and even identical models
can easily be 'tuned' to be different by swapping valves and other
components. This is a great part of the appeal for me - they allow me to
'tweak' a sound that I like and which I think sounds best or faithful
according to *my* own ideas.

What's scary is just how quickly I can accomodate to the sound of different
systems and it indicates to me that, for all the talk of 'fidelity' to
mastertapes (real or imagined) or live events (whether attended or not),
that we *all* do a lot of kidding ourselves that we have *neutral* and
'accurate' systems.....

Moreover, I don't think that one amp/speaker combination is ever likely to
be 'ideal' for *all* different types of music and prefer to run a number of
different setups (there will be 4 of them on the go, later this afternoon)
for different types of music - choirs or solo female vocals accompanied by
an acoustic guitar vs. electronic dance/trance/techno being two fairly good
examples of music that benefit from quite different setups IMO...

But then, that's just me.... :-)

In article ,
Jim Lesurf wrote:
My recollection is that the 33 does not have a very flat response even
with the controls set as near flat as possible compared with more modern
units. FWIW my experience is that even quite small changes in overall
response can be audible.

It has, of course, got a tone control bypass switch.

IIRC, the pickup preamp had distinctly marginal headroom on the 33.

--
*Never underestimate the power of stupid people in large groups

Dave Plowman London SW
To e-mail, change noise into sound.