On Sat, 09 Oct 2004 19:25:32 GMT, Bob Latham
wrote:

I had an interesting experience this morning. I have been helping a hi-fi
newbie at work choose his first AV system. When it came to amplifiers I
had advised him to try the Arcam AVR300 which suited his requirements and
would nicely fit on his tv/hi-fi rack. Plus I knew of Arcam's excellent
after sales service and I have an AV8/P7 which I am very happy with.

All was well until someone suggested that it might be interesting to try
the Denon amp at a similar price as it was getting good reviews. It was
wired in to exactly the same cables and speakers and the speaker levels
(balance) were set the same.

My newbie mate was first to indicate his feelings. The Denon was, to my
ears considerably more alive and dynamic than the Arcam both on CD and DVD
music videos. The Arcam was warm and cuddly but very laid back. He decided
on the Denon and it was easy to have a preference.

This friend of mine had never been in a hi-fi dem in his life before and
because we were using a projector for the music DVDs the room was in
almost total darkness there was no subtle facial expressions guiding him
at all. Don't anyone ever tell me all good amps sound the same, they
simply don't,

Yes, they do.

unless of course these amps are both not good. I will
concede that it could have been the DACs that were so different as we did
not use an analogue source but even so...

Incidentally, I wouldn't think the shop wanted that result as the Denon
was 300UKP cheaper.

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

Don't anyone ever tell me all good amps sound the same, they simply don't,

Yes, they do

Another vote for "they simply don't" here. As we should have expected, opinions
are completely divided.

=== Andy Evans ===
Visit our Website:- http://www.artsandmedia.com
Audio, music and health pages and interesting links.

Bob Latham wrote:

In article ,
Stewart Pinkerton wrote:

On Sat, 09 Oct 2004 19:25:32 GMT, Bob Latham
wrote:


[Snip]


Yes, they do.


No they B. don't. Another example, My Yamaha amp (recently retired) always
sounded hard and harsh to me, I purchased it from a box shifter as it was
a good price and I fancied a dabble with surround sound. On swapping to
the Av8/P7 the improvement in sound was staggering and it mattered not
which was played the loudest the AV8/P7 blew away the Yamaha by a good
margin.

it doesn't matter which amp can go loudest, they both have to be level matched
and be able to drive the speakers without clipping.

snip shrillness comments




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


Rubbish! I'm sorry but this is so much hogg wash, the differences were so
obvious immediately and the shop clearly would have preferred to sell the
other amp but had to agree the Denon had the legs. Besides I don't know
anyone that listens to their hi-fi in an LMDBT manner they just switch it
on and turn up the wick until it sounds right, that's what we did and the
Denon was better QED.

uhm, who does listen to their hi-fi in a LMDBT manner? that would mean switching
between 2 sources or 2 amps. The LMDBT manner is meant to provide an unbiased
comparison between different digital sources or amplifiers, ie to be used when
purchasing new equipment (or to perform experiments)

I also know that
amplifiers sound different depending on what you place them on, I don't
think this, I know it! (True story told before).

could you elaborate? I'm thinking of hum or other nasties that the amp picks up
from the surroundings (e.g. like placing pre and power amps too close to each
other, stray RF sources). Or does this indicate poor amp design?


What would you have people do, buy the cheapest amp that had the
facilities they need and ignore the sound?


well, if the amps sound the same and are capable of driving the speakers ...

On Sun, 10 Oct 2004 13:19:20 GMT, Bob Latham
wrote:

I also know that
amplifiers sound different depending on what you place them on, I don't
think this, I know it! (True story told before).

You do know you said that out loud? He he...

I've never seen anyone do a better job of blowing his credibility
while trying to score a point.

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

In article , Andy Evans wrote:
Don't anyone ever tell me all good amps sound the same, they simply don't,

Yes, they do

Another vote for "they simply don't" here. As we should have expected, opinions
are completely divided.

I wonder if you or someone else could explain why they don't (or why
they shouldn't)?

As background this is my perspective:

* As a former engineer (who has designed and built audio amplifiers in
an amateur capacity), I design an "amplifier" to amplify. For the range
of expected loads and the range of expected output voltages, the output
voltage differs from the input only in amplitude (usually with a small
delay - 1.5 microseconds or so).

* Loudspeakers and rooms are still so variable that adding one more
variable is not a good idea if reasonable accuracy - "high fidelity"
- is a goal. My goal *is* high fidelity to the recording and not to
make the recording more euphonic by using the amplifier. As such I
believe the amplifier should be "transparent" and that translates into
the goals above.

* If the load (the loudspeaker's impedance) is outside the design limit
or the amplifier is asked to produce a greater output than specified
then I am sure the amplifier could have its own sound but that's an
abnormal operating condition.

The logical outcome of the above principles is clearly (to me) that an
amplifier that is properly designed and is operating within its limits
cannot have its own sound. Thus "all good amplifiers sound the same."

Of course it could be argued that for the current state of the art or
for a specific budget the above goals cannot be achieved. However I
assume at least the state of the art is sufficient leaving only budget
as a possible consideration. It could also be argued that the above
goals are not shared by everyone.

--
John Phillips

Bob Latham wrote:

Rubbish! I'm sorry but this is so much hogg wash, the differences were so
obvious immediately

Er. the *POINT* of a DBT is to differentiate between the 'immediately
obvious differences' that can be created by poor test conditions.

Unless you can devise a test that shows you werent influenced in your
NON DBT tests, nothing you say means anything.

This is *not* to say that some differences arent so staggeringly obvious
that you dont even need to run tests, but you cant dismiss DBT testing
for subtle differences, just because you can tell the difference between
grossly differing systems without a DBT...

On 10 Oct 2004 13:19:10 GMT, ohawker (Andy
Evans) wrote:

Don't anyone ever tell me all good amps sound the same, they simply don't,

Yes, they do

Another vote for "they simply don't" here. As we should have expected, opinions
are completely divided.

It's not a matter of opinion in my case, it's a matter of many
experimental results under bias-controlled conditions. IME, any amp
which sounds different from a nominally competent SS amp, is
*colouring* the sound, and hence I'd define it as a *bad* hi-fi amp.
--

Stewart Pinkerton | Music is Art - Audio is Engineering

On Sun, 10 Oct 2004 13:19:20 GMT, Bob Latham
wrote:

In article ,
Stewart Pinkerton wrote:
On Sat, 09 Oct 2004 19:25:32 GMT, Bob Latham
wrote:

[Snip]

Yes, they do.

No they B. don't.

Sure they do - why wouldn't they?

Another example, My Yamaha amp (recently retired) always
sounded hard and harsh to me, I purchased it from a box shifter as it was
a good price and I fancied a dabble with surround sound. On swapping to
the Av8/P7 the improvement in sound was staggering and it mattered not
which was played the loudest the AV8/P7 blew away the Yamaha by a good
margin.

It probably had high HF IMD, pretty common in that range, and I
suspect that was what gave away the AX-570 in my own tests. OTOH, if
you haven't tried that comparison under *blind* level-matched
conditions, then your opinion is not of any real value.

A friend of mine has a Linn amp which has blown up and is away for repair.
He borrowed the Yamaha on a Friday night about a month ago. When I saw him
on the Monday morning after thanking me for the loan he commented "its a
bit shrill isn't it?".

By pure coincidence (honestly) after talking to the hi-fi shop yesterday
about the Denon being better than the ARCAM AVR300 another guy in the shop
said and I quote "The Denon does sound lively compared to the AVR300 but
doesn't have the harsh sound the Yamahas tend to have". Exactly my
experience without any way for the guy to know my view first and no
listening test to be done wrong.

The smaller Yamahas I have indeed found to be bright, the big 100 watt
2-channel ones seem to have this under better control, but I agree
that in my own comparison, the Yamaha was distinguishable. This does
not affect the argument that 'all good amplifiers sound the same', it
simply confirms the notion that certain Yamaha models have audible
deficiencies. Note also that in my comparison, a 'rave review' pair of
Denon POA 6600 monoblocs came out very badly, having very shrill
treble and being tossed out at the first comparison. My own Denon PMA
350 II is certainly distinguishable from my 'good' amps. In this case,
I suspect the harshness is down to switching distortion as well as
treble problems.

unless of course these amps are both not good. I will concede that it
could have been the DACs that were so different as we did not use an
analogue source but even so...

Incidentally, I wouldn't think the shop wanted that result as the Denon
was 300UKP cheaper.

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

Rubbish! I'm sorry but this is so much hogg wash, the differences were so
obvious immediately and the shop clearly would have preferred to sell the
other amp but had to agree the Denon had the legs.

Yeah yeah, if I had a quid for the number of times I've heard that
one...................

Just try it.

Besides I don't know
anyone that listens to their hi-fi in an LMDBT manner they just switch it
on and turn up the wick until it sounds right, that's what we did and the
Denon was better QED.

Bull****. Just *try* it.

I don't give a monkeys what the measurements say (I have electronic
qualifications) I know those measurements were not taken driving those
speakers and neither were they taken using music. I also know that
amplifiers sound different depending on what you place them on, I don't
think this, I know it! (True story told before).

Bull**** - unless it's a *really* bad amplifier!

What would you have people do, buy the cheapest amp that had the
facilities they need and ignore the sound?

I'd have them buy the cheapest amp that had the power and facilities
required, and that sounded just like any other good amplifier. That's
the other reason I keep the Krell - it's a useful reference.
--

Stewart Pinkerton | Music is Art - Audio is Engineering

In article , Bob Latham
wrote:
In article , Stewart
Pinkerton wrote:
On Sat, 09 Oct 2004 19:25:32 GMT, Bob Latham
wrote:

[Snip]

Yes, they do.

No they B. don't. Another example, My Yamaha amp (recently retired)
always sounded hard and harsh to me, I purchased it from a box shifter
as it was a good price and I fancied a dabble with surround sound. On
swapping to the Av8/P7 the improvement in sound was staggering and it
mattered not which was played the loudest the AV8/P7 blew away the
Yamaha by a good margin.

So why would you describe the Yamaha as a "good" amplifier? Why not simply
conclude that it wasn't a satisfactory design (or had a fault)? - i.e. not
good at all...

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

On Sun, 10 Oct 2004 15:50:06 GMT, Bob Latham
wrote:

In article ,
Don Pearce wrote:
On Sun, 10 Oct 2004 13:19:20 GMT, Bob Latham
wrote:

I also know that
amplifiers sound different depending on what you place them on, I don't
think this, I know it! (True story told before).

You do know you said that out loud? He he...

I've never seen anyone do a better job of blowing his credibility
while trying to score a point.

Sorry to be utterly thick but having read, read again, and again I still
don't understand any of it. Firstly I was not point scoring I was making a
statement of belief, as for this "said out load" comment, no idea what
you're on about but it seems you were trying to personalize a
disagreement. This is usually done by the losing side in my experience.

Cheers,

Bob.

You were not making a statement of belief - read what I quote from you
"I don't think this, I know". So you actually deny that it is belief,
but is fact. So make your mind up - do you believe it, or do you know
it? There is a huge difference.

Anyway, how exactly do you think (believe if you like) you are
advancing the argument by posting such unmitigated ********? If you
believe you are helping your side of the picture, think again - you
are just sounding stupid - almost as if you were religious or
something.

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