Should Amplifiers Be Transparent?

[moktan]

to wade right in with my two paise...
the problem with measurements is that they are reductionist exercises..at the most, they just provide that illusion of clarity that comes with the over simplification...
measurements could get more relevant if one could assign a weight to those numbers in terms of how they contribute to the overall perception of the musical information...but that as things stand is a pipe dream ...

 

[arj]

There no doubt that measurements give some information, but it is only part truth. there are so many aspects for which we do not have measurements or even know what to measure.

To give an example, as written by Robert Harley, many years back audiophiles had maintained that digital cables do make a difference and the objectivists /engineers maintained that a cable is a cable and being a digital signal it cannot make a difference.

it was then that the impact of Jitter in a cable was "discovered" and how threshold values could cause timing/data error

Similarly many tube amps actually measure worse in aspects like THD/SNR. Although you can call them inferior to a well measuring amp technically, if it sounds better in tonal accuracy then i would think of it as a better amp.

in fact while measurements of speakers/amps if done well would be a better story but the lack of standards/regulations or even proper parameterisation make it not so reliable.
the standard specs available for an amp say Frequency Response, THD, Phase, Crosstalk and Signal-to-Noise Ratio thats it.

Any amp would have decent enough figures to meet expectations above and could sound as bad as a USD10 amp or good a USD10K amp (i dont meant to say all 10K amps are great..but they better be better than a 10USD one !)

On the other hand amps with a freq response of 30Hz to 20Khz could sound so much better than one with 5 Hz to 50Khz.
and vice versa.

while the measurements are only a hygene factor they really do not mean much regarding the Quality of sound.

While some of the measurements done by John Atkinson are a lot more helpful, in the end it is only the ear which is able to get that ultimate decision on emotional satisfaction which we would all agree is unmeasurable

 

[shershah]

to wade right in with my two paise...
the problem with measurements is that they are reductionist exercises..at the most, they just provide that illusion of clarity that comes with the over simplification...
measurements could get more relevant if one could assign a weight to those numbers in terms of how they contribute to the overall perception of the musical information...but that as things stand is a pipe dream ...

i mean no offense to anyone -

Mr. Moktan - you seem to have the depth, and so i will deign to engage you-

i say this to you - "you give me the numbers and i will give you the music - it is all in the numbers, that is how we sense the world"

please do not take offense because i have been forthright and honest -

a thousand pardons

 

[moktan]

i mean no offense to anyone -


i say this to you - "you give me the numbers and i will give you the music - it is all in the numbers, that is how we sense the world"


a thousand pardons

the first thing i would like to reciprocate is a number, a transfer of apology ..'one' that is implicit in the 'thousand pardons' invocation...
but my current feeling is that by quoting numbers etc technically savvy guys try to overwhelm and smother the opinion of subjectivists who have to take shelter in words instead of ones and twos and sundry other decimal points and percentages to justify their preferences....

.

 

[shershah]

the first thing i would like to reciprocate is a number, a transfer of apology ..'one' that is implicit in the 'thousand pardons' invocation...
but my current feeling is that by quoting numbers etc technically savvy guys try to overwhelm and smother the opinion of subjectivists who have to take shelter in words instead of ones and twos and sundry other decimal points and percentages to justify their preferences....

.

Ah! Moktan - you are an intelligent man

but transparency of audio amplifiers is the topic being discussed here, and i adjure you to abjure the abstract and stick to "the numbers"

but, yes - i must agree with you - the "experience" is everything

including all the "numbers" from 0 to finite measurement

 

[moktan]

but transparency of audio amplifiers is the topic being discussed here, and i adjure you to abjure the abstract and stick to "the numbers"

i think the degree of 'transparency' (in an optical sense and not the Transparency International sense ) is measured by a number called refractive index..does such a number exist for amplifiers??.....
was wondering why so much of the aural borrows analogies from the visual..speaking of color..i think history of science bears us out that when newton observed colorful halo effect around the stars that he captured through his telescopes..he first blamed the instruments...since no amount of grinding could get rid of those chromatic aberrations..he concluded that color was there in the light itself..instead of the contraptions that were used to capture them.....

 

[shershah]

i think the degree of 'transparency' (in an optical sense and not the Transparency International sense ) is measured by a number called refractive index..does such a number exist for amplifiers??.....
was wondering why so much of the aural borrows analogies from the visual..speaking of color..i think history of science bears us out that when newton observed colorful halo effect around the stars that he captured through his telescopes..he first blamed the instruments...since no amount of grinding could get rid of those chromatic aberrations..he concluded that color was there in the light itself..instead of the contraptions that were used to capture them.....

and then came Zeiss and Leica with their apochromatic optics-

and newton was an extra-ordinarily gifted man - a clever man

 

[shershah]

HEY!!!

let us call it quits -

this thread has been reduced to meaningless drivel within the span of a few posts.

let us REALLY discuss what should be discussed - "TRANSPARENT AMPLIFIERS"

i am outta here.:indifferent14:

 

[square_wave]

Measurements (whatever they measure) have no such biases. They truthfully tell you what they are 'hearing' and, in that sense, are more consistent and reliable.

Cheers

Sorry. Measurements will never truthfully what you are hearing. Measurements are just a basic building block. It is where you start. What the amp is capable of musically is what the human ear has to comprehend and validate. Unless it passes this test, the amp is useless whether it measure right or not !

If an average joe with basic electronics knowledge spends enough time on diyaudio.com for an year, he can put together an amp or dac with amazing measurements. Making music is a different ball game !

 

[no1lives4ever]

Since there is some talk about good sounding tube amps, here is some food for thought.

In most studios, you will find a lot of tube gear. Any decent studio will not function w/o the tube gear. Now where are these tubes used and for what purpose?

What you will find is that tubes used in studio are used mainly in the preamps, compressors and guitar amps. In all these cases, the tubes are used because of the way they handle the signals when they are over driven. An over driven tube has a warm sound that all recording engineers love. The easy way to add warmth to any signal is to pass it through a tube compressor or a tube compressor simulator when working with a digital system. Similarly tapes and tape emulators are used for the unique characteristics of a magnetic tape when over driven.

To me this clearly explains why people love tube amps and why they are still in vogue in the audiophile community. A well designed tube amp will distort the signal such that it sounds warm and nice to the ears. This also explains the horrible THD figures on some very good sounding tube amps. Most of those good sounding amps will color the audio signal to make it sound good. But then you get to the point where the amp is adding to the music to make it sound good.

@Kanwar can you shed some light on the relative transparency of tube amps and also about why tube amps used in some pa stacks?

-- no1lives4ever

 

[shershah]

pa stacks?

he! no1lives4ever -

for sound reinforcement in large arenas and stadia-

ONLY SOLID STATE WILL DO -

with massive capacitor values for each channel

tubes for the capture - yes, perhaps!

http://www.hifivision.com/amplifiers/16623-should-amplifiers-transparent.html

hehe

 

[Dr.Bass]

If you had read my statements carefully, you would have understood what I have always been maintaining. That measurements are the building block of a good design that ensures that the product meets certain specifications. The designer then builds up from there to get the sound that he wants. I have always maintained that measurements and hearings (or sound and music) are complimentary, not contradictory, nor opposing. But, if you say measurements are meaningless and only hearing matters, then I am afraid you are wrong.

One of the issues with hearing is that the outcome is very subjective. For example if I blindfold a man, and make him hear a amp that has a measurable high noise to signal ratio, and he says he likes the music and that it is good - what do we conclude? That he does not know music or that he is lying? That is the reason most blindfold tests have consistently failed.

Even seasoned auditioning experts have consistently come to wrong conclusions when they have undergone blind tests. Every time you change your source, amp, speakers, or even cables, you hear a different sound, even if the variations are very minor. But the sound is different. Which is better? What you hear before or what you are hearing now? You will look like a fool if you say the wrong thing. So what do you do? You end up making mistakes.

Add this to the fact that we all have different tastes for music and ways to listen to it. I like to play my music softly is a quiet room. Someone else may like to blast his ears at 90dB. I like drums to be tight. Someone else may like drums to be boomy and rolling.

Measurements (whatever they measure) have no such biases. They truthfully tell you what they are 'hearing' and, in that sense, are more consistent and reliable.

Cheers

Where do I start:

1. I never said measurements are useless. You are putting words in my mouth. I just said they are just guidelines to start with. I clearly admitted that audio gear is after all physics, so measurement is common sense.

2. A blindfolded man can very well like an amplifier with low SNR because the PRAT and tonality were excellent. He was neither lying nor is he incapable of judging music reproduction. I think you still did not get my initial point that things like PRAT and Tonality cannot be measured by scientific instruments even though they are fundamental building blocks for music reproduction. If you know of an instrument like that, please suggest, I will be the first one on this forum to buy it.

 

[Asit]

Should amplifiers be transparent?

Yes.

Can they be transparent?

No.

The above is my view based on the following argument.

Sound (even a musical sound of a single solo note, for example the middle octave C on any instrument or vocals) is made up of many components with a variety of frequencies (only the so-called fundamental freq would correspond to the mid-octave C in the example). The relative strengths of these components make the 'tonality' of the sound, technically called the 'quality' of the sound which makes two voices singing the same note different.

For argument's sake, even if it is assumed that a certain amplifier has zero distortion, the electrical signal in a physical amplifier has to pass through passive elements. Any energy carrying signal when passing through a medium (the passive elements) necessarily changes the 'quality' (i.e., the relative strengths of the freq components) because the effect of the medium is different for different frequencies. Hence, no matter how much we may like an active element to be neutral and transparent, any physical implementation would necessarily change the tonality, however little. Hence I think , any perfectly neutral single piece of equipment is an illusion. I do not think it is possible (of course one can come pretty close to neutrality by clever choice of passive elements).

However, just like what Dr. Bass said some pages ago, one may strive to make a total system comprising of source, amp and speakers (and cables) as neutral as possible (again through clever combination of elements) if one likes that kind of thing. I certainly like to hear Ali Akbar's sarod sound through my system as close to the original unamplified sound (albeit in a closed room with a bit of peripheral noise).

I was itching to write my view on this for a while now. I was very hesitant though, because whatever I have written in the above is firstly a bit abstract, and I have to admit, a bit speculative too.

I have also my views on measurements, on why they may hide more than they show. But that's for another time, if I can gather some more courage to write naive things in front of vastly knowledgeable participants of this thread.

Regards.

 

[sidvee]

Since there is some talk about good sounding tube amps, here is some food for thought.

In most studios, you will find a lot of tube gear. Any decent studio will not function w/o the tube gear. Now where are these tubes used and for what purpose?

-- no1lives4ever

As I understand there are 3 environments of sound reproduction under discussion here:

1. Home Audio
2. Closed Studio
3. Open Venue

I agree that in the first 2 there is extensive use of tubes, but I am not too sure if tubes are used in the third.
Regardless if tubes are used and liked for the first 2, then measurements of these equipment will not be impeccable as I alluded to in my first post, and the very fact that they are being used proves a point that there is demand for equipment that does not necessarily measure great but apparently sounds good.
I am not trying to make this a debate between tubes and ss but just pointing to a fact that there is a big difference between Pro and Home audio equipment.

Cheers
Sid

 

[ajay124]

Frederic Chopin's Fantasy Improptu in C Sharp Minor.Performed by some famous Chopin interpreters.All of them 'colour' the music in different ways.Who knows which version is true to the intentions of the composer?
Yundi Li
YouTube - Yundi Li - Chopin "Fantasie" Impromptu, Op. 66
Artur Rubinstein
YouTube - Chopin - Fantaisie Impromptu, Op. 66 (Rubinstein)
Valentina Igoshina
YouTube - Chopin - Valentina Igoshina - Fantasie Impromptu

*This thread has contributed a lot of valuable information and I intend to read all the posts at leisure to learn what I can.But I feel the end objective of audiophilia is the music we listen to.Audiophilia divorced from music is ultimately an academic exercise doomed to reach a 'dead end'.What we like and the degree of 'colour' we like is as much of an individual choice as the colour of the clothes we wear.I doubt that a valid,universally acceptable way will ever be discovered to measure or pin down what is coloured and what is transparent.

 

[captrajesh]

At least in their case, they are groping a tangible thing.

 

[vivek.saikia]

At least in their case, they are groping a tangible thing.

Ha ha........Good one Cap'n hyeah: hyeah:

 

[arj]

..But I feel the end objective of audiophilia is the music we listen to.Audiophilia divorced from music is ultimately an academic exercise doomed to reach a 'dead end'.

I guess the problem is of trying to explain Art through science. it is like trying to define the beauty of a photograph or a painting scientifically with parameters.


I sincerely hope Love and taste are not parameterized too

..What we like and the degree of 'colour' we like is as much of an individual choice as the colour of the clothes we wear.I doubt that a valid,universally acceptable way will ever be discovered to measure or pin down what is coloured and what is transparent.

What you have put in a nicely eloquent and pictorial metaphor is what i had been trying to put in my own vague, slightly verbose and lax articulation ie "neutrality" is very person specific

 

[captrajesh]

Ha ha........Good one Cap'n hyeah: hyeah:

Thank you buddy.

 

[Asit]

Captain,
Although you put that picture up jokingly, you probably had no idea that portrays perfectly what I think of measurements of amp parameters.

The problem with measurements, I think, is that currently there are no complete set of amp parameters that should determine the audio properties of an amp uniquely. That is the reason two different amps measuring the same or very close, generally sound so much different. Given the complexity of the issue, I think we are far from determining the complete set.

As I said, the captain's elephant measurement already gives us a wonderful example. Let me add my usual boring example. Two spherical balls are given with same diameter and same weight. Are they really same? Not necessarily. One ball could be hollow, another one could be solid; one could be red, the other blue. Unless we know a minimal but complete set of parameters to measure, we cannot determine the object uniquely. An electron at rest, for example, is determined completely by its electric charge, mass and spin. There is nothing more to it. If you happen to meet such a gal while crossing the road, it is bound to be an electron.

I have nothing against measurements. They certainly give one something quantitative to look at. It may help in some way. But until one finds a complete set of measurements for amplifiers, the incomplete set as of now is of very limited use.

I think, in a very different language, arj also have tried to say the same thing especially when he brought up the unknown factor of jitter in his recent post.

Regards.

Note added later:
I consciously avoided bringing in music in my discussion. It only complicates already a very hard problem. After all, an amplifier can amplify any audio signal. I am looking at it as a piece of electronic equipment and I want a minimal but complete set of parameters to measure so that a given amplifier can be understood uniquely. Unfortunately even a reasonably complete set of measurements is lacking.