All amplifiers do not sound the same

[Sokel]

So it is a mechanical issue then, not psychological? Fair enough.

Not sure temperature is comparable since we adapt to that. When I worked in cold storage I never felt cold in winter but summer was too warm for me. When I left that job I soon adapted back.

You're right about adaptation, I was never able to adapt to this.
At its worst it even causes me a round headache, I'm a walking RTA about it

 

[DavidEdwinAston]

https://geocities.restorativland.org/ResearchTriangle/Lab/6722/pwint1.txt

Peter Walker: An amplifier should, within its limits of voltage and rate of change of voltage,
(which is slew rate limiting) if you keep within those two it should be very much
better than any program material. These are the things that are measured at .01
per cent or .05 per cent. But what is listened to is usually a program with 2 or 3
per cent distortion in the first place. That's the least you can get on records,
tapes, and such things. Listening tests are usually not done in this region of .01
percent distortion. I'm quite convinced within that range the amplifier is just as
perfect as you like to make it. It's quite possible to put 50 amplifiers in cascade,
each one into a load, potted down into the next one, and to listen to the 50th one
or to listen to the first one, and the sound will be virtually the same. So I think you
can make an amplifier just as good as you like, and no more different than a
piece of wire. But where they vary, when these tests are done, are a whole lot of
areas. To start with, you can compare one amplifier with a bass cut-off of 20 Hz
and another one that goes right down to DC. If you've got a program with a bit of
fluffing going on at 5 Hz or so, the speaker cone in one case will be moving, and
in the other case it won't be moving, so the sound from the speaker will be
different. This isn't really a condemnation of the amplifier, it's that they shouldn't
have this 5 Hz stuff there in the first place. So if you compare an amplifier with a
straight wire, you've really got to make the straight wire have the same
bandwidth as the amplifier, and the same terminating impedance as the
amplifier. Once you do all these things, then the amps will be just as good as the
straight wire. The peripheral effects are what get people into trouble. You can
see why you find these differences in amplifiers. You can always find them. If
people test two amplifiers and say, "These sound different," there's no magic in
it. Spend two days, maybe a whole week in the lab, and you find out exactly why
they're different and you can write the whole thing down in purely practical,
physical terms. This is why these two sound different, and the cause is usually
peripheral effects. It is not really a case of good or bad amplifiers, it's that the
termination impedances are wrong, or something of that sort.

Thank you for posting this. As a long time user of modern Quad SS amplifiers, and as someone who attended a Peter Walker demonstration at a distant Harrogate hifi show, I do find this reassuring.

 

[Mart68]

It really depends on the speaker, the PMC Twenty.22's I had were definitely sibilant. Based on Amir's review of the Twenty.21 (same tweeter as the 22, just a smaller woofer) I'd say that's not surprising. Never had electronics cause it though.

Agree that it can be the speaker in some cases. That series of PMC were pretty terrible in measurement, curiously not so bad in listening as I expected. But then when you see the price tag...

 

[Koeitje]

Agree that it can be the speaker in some cases. That series of PMC were pretty terrible in measurement, curiously not so bad in listening as I expected. But then when you see the price tag...

They were terrible to listen to. I got rid of them long before I joined ASR. Apart from the excessive treble and sibilance it also did some weird things in the bass. At certain lower frequencies it sounded distorted and there was a lot of port noise.

 

[LTig]

According to https://boomspeaker.com/amplifier-power-required-calculator/, it's more 2500W!

This is probably not in a room (free field) and for one speaker. My calculation for this case is 110dB + 2*6dB (distance) = 122dB per speaker. This is 34 dB above 1W hence roughly around 1600W.

 

[Foxxy]

Maybe, but when I think how many different speakers I've had over the years (including B&W), at least 10 different rooms and god knows how many turntables, amps, cd players, tape decks. And never been bothered by sibilance. And yet some people find it a big issue that changing any of the equipment fails to cure. They blame the recordings, but other people don't perceive a sibilance issue with those same recordings,

Isn't tinnitus created by the brain? Could perception of sibilance be similar? (I'm speculating, obviously).

Since I have some tinnitus and extremely susceptible to sibilance, there might be some correlation.

 

[peng]

As one of these people I can state in any possible way that's only very few recordings that bother.
The main reason is playback chain and room, with speakers being the dominant cause (could very well be a load dependent amp as well,etc )

Even the slightest rise at 4kHz to 6kHz does the trick and new B&W is amongst these along with a bunch of studio monitors.
But it's not only the 4-6kHz that does it, it's more a combination of that along with thin midbass usually.

May be, but imo it is more to do with the recording/mastering, not the amplifier that measured well in FR and distortions. If the lightest rise at 4-6 kHz is the cause, then it can be proved easily but apparent not, so... Does the lightest mean less than 0.5 dB, for example, if it is, again it would be very easily to do some experiments.

I don't know why people focussed on amplifiers that measured so well in many bent tests, and don't seem to consider the signal chain in the recording and mastering process when that obviously already include so many electronics such as mics (multiple usually in most cases?), preamps, amps, processors, adc/dacs, even speakers in some cases and even in live recordings. With so many things involved, it is hardly practical to just focus on consumer class hifi audio amps.

 

[OldHvyMec]

No. Your fantasy I suppose.

I need to castrate some goats in the front 20 and go listen to my broken TUBE AMP in the cut shed. I'll be thinking of the music, NOT the goats!

BUT by all means, you have a swell day.

Nah... they haven't/weren't, an old wives tale.

Dodd. Samra, Herron, Tillis, Barton, Carver, Pass, STI, James B., Atmasphere class D, and their valve amps, ALL the early McIntosh, all the early WD, all the early Marantz SS and Valve amps, Early Krell Class A, Quad, Early ICE vs Early NCore, Cary valve amps from valve to valve series are as different as night and day, Cary SS especially early class A/B. Adcom EX: GFA565 vs GFA5500, 5800, or even the 7400/7500. Early Emotiva sounds like a blanket was thrown over them, with many small planar/ribbon speakers I use.

The personal/factory upgrades on Cary valve amps don't do a thing, you got me rolling here. I've done at least 30 upgrades on Cary's different models alone.

Don't tell me, Records suck, valve amps are inferior, RtR is a thing of the past, and digital is the best thing to ever happen since sliced bread. Though I do agree it is pretty cool and fairly simple to get close.

SOME people know how to change things. OTHERS couldn't change their dippers.

Listen to a class D Atmosphere vs a Nord NC500 rev d. They sound different, and it's not subtle over protracted periods or several listening sessions.

The manufacturer's builder (Ralph) clearly states he VOICED the amp to sound and appeal to valve/tube amp enthusiasts.

Regards

 

[JSmith]

clearly states he VOICED the amp

How?


JSmith

 

[Petrushka]

How?


JSmith

Carver did it. I believe he added a resistor to reduce damping.

 

[Sal1950]

Who even came up with this bullshit?? And why was there no backtalk?? Why was this allowed to stand???

The subjective community posted this BS in an attempt to discredit the objective community, claiming it was our position.
Nothing could be further from the truth.
What is true is that amplifier design has been a solved issue for a number of decades now when they are built to modern standards.

"In controlled double-blind listening tests, no one has ever (yes, ever!) heard a difference between two amplifiers with high input impedance, low output impedance, flat response, low distortion, and low noise, when operated at precisely matched levels (±0.1 dB) and not clipped."
Peter Aczel (https://www.biline.ca/audio_critic/critic1.htm)

That is the statement I like to refer to.

Yes this is true

 

[oleg87]

Not sure I’d call adding an unpredictible interaction with specific speakers “voicing”, but whatever floats people’s boats, I guess…

 

[post]

Who even came up with this bullshit?? And why was there no backtalk?? Why was this allowed to stand???
Objective?? Objective would be "all amplifiers which reach sufficient thresholds in key parameters will sound the same."
Done.

This stupid Dunning-Kruger inaccurate pseudo objectivist bullshit has cost me a TON over the years. I kept changing speakers and treat my room and never be happy. Turn out I should have taken a good chunk of change and get a good studio amp first.

There is nothing more to say.
I am only angry because it cost me so many years of my life. Those are limited. I want them back

It's very sad that you had to suffer many years of bad sound.
But mostly its also your fault to accept the wrong ideas and not do your research. It's too late now, but generally you have to have a good source, good amplification, good speakers and a good sound treated room to have a good sound. Skimp in any one of these and you will have a less satisfactory sound.

 

[OldHvyMec]

How?

Where and when he fed the feedback into the different sections of the amp. Ask Ralph, he is quite happy to converse with any civilized person who posts to him. He'll usually tell them how to get likely results through different means without giving up proprietary information. He has his own personal flavor added that can surely be MEASURED! He spent a few years picking and modifying the GaN class amp modules he uses.

If you ever get a chance, look inside any of his amps (especially any valve-based amp/preamp; they are absolute works of art to any builder.

He built one of the best LS valve preamps I've ever heard for a particular type of speaker. It was modded and made for Brian Cheney's testing of all of his JVC/AC ribbon/ Neo 8-based planar speaker systems that he was VIOCING to his personal taste. BTW, VMPS won best in show so many times at CES, I quit counting and THAT Preamp was there a few times for important shows.

I personally love the BY EAR voicing. VMPS and the philosophy of low-cost products (when they work together) and knowing when to spend a few bucks on build quality, like wiring, soldering the wires to the drivers, the quality of the solder over protracted periods, the quality of the binding post, voicing the cabinet for the amount of resonance. Even using different drivers for different people.

Brian putty-pinched the passive radiators in the sub/bass systems in all of his speakers with very few exceptions (there were very few tube ported speakers). He used it to dampen the amp, cabling length/size, then get the lowest possible octave and not have BOOM in the room. He did it by removing a soft putty mass, a thumbnail at a time. THAT is called voicing, and it doesn't stop at an amp, including drapes, floor covering, and decoupling the system either partially or completely.

Believe it or not, most avid listeners don't like flat as a board systems, untreated rooms, and DSP. They really prefer Human Sound Processors. You do realize the first computers were human. Look it up!! 16.4 billion ears, and they all differ slightly from one another.

YES, there is a thing called VOICING.

Besides that, I need to go see about the goats.

Regards

 

[Mnyb]

Not sure I’d call adding an unpredictible interaction with specific speakers “voicing”, but whatever floats people’s boats, I guess…

Good amps have predictabale interactions hence no voicing thus avoid esoteric high end if you can , be vary carefull if you must.

 

[Bruce Morgen]

I wonder how long it will until some enterprising builder offers a Purifi-based power amp with a tunable front end circuit so the users can impose their own "voicing."

 

[Mnyb]

I wonder how long it will until some enterprising builder offers a Purifi-based power amp with a tunable front end circuit so the users can impose their own "voicing."

Many class-D amp builders offers front ends with a choice different op-amps for this already ? I does not have to do any actual difference as longa as the customer is happy .

 

[Bruce Morgen]

Many class-D amp builders offers front ends with a choice different op-amps for this already ? I does not have to do any actual difference as longa as the customer is happy .

I'm talking about built-in tunability via back panel controls amd/or selector switches that actually do "voice" the signal, e.g. controlled amounts of negative feedback or tweaks to the FR curve.

 

[Sokel]

I'm talking about built-in tunability via back panel controls amd/or selector switches that actually do "voice" the signal, e.g. controlled amounts of negative feedback or tweaks to the FR curve.

Tone control like?
Aren't there any integrated amps out there using class D modules and also having such features?

 

[Bruce Morgen]

Many class-D amp builders offers front ends with a choice different op-amps for this already ? I does not have to do any actual difference as longa as the customer is happy .

I'm referring to back panel adjustments to control things like the amount of negative feedback or even the FR curve -- not DIY component swaps.