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

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

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.

On Sun, 10 Oct 2004 10:14:19 +0100, "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.

Why not? What's your alternative?

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 ?

This old warhorse gets dragged out regularly. I use insensitive 3-ohm
speakers, and while my Audiolab (and several other amps) sounds just
like the Krell, it gets *very* hot after half an hour or so at high
SPLs. Hence, the Krell is there because it drives the speakers with
ease, not because it sounds different.

--

Stewart Pinkerton | Music is Art - Audio is Engineering

Stewart Pinkerton wrote:

On Sun, 10 Oct 2004 10:14:19 +0100, "Richard Wall"
wrote:



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 ?


This old warhorse gets dragged out regularly. I use insensitive 3-ohm
speakers, and while my Audiolab (and several other amps) sounds just
like the Krell, it gets *very* hot after half an hour or so at high
SPLs. Hence, the Krell is there because it drives the speakers with
ease, not because it sounds different.


so did you get the Krell or the Apogees first?
And what speakers were you using before the Apogees?

Hmmmm, I don't like the chances of running your Apogees through my 8000S
.... my amp gets really hot in the Australian summer just driving a
nomimal 8 Ohm pair of speakers ...

(of course, it could be because my room gets the afternoon sun and the
amp could probably do with more clearance in the rack for ventilation)

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

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.