Our concerns about numbers, harmonics, distortion, square waves, THD, measurements

[destroyer X]

the main thing in their lives... alike a God... the correct thing to be done... the correct way to know things...and them someone say they have loose their time searching for fishes into the desert..... for sure this is not easy..but someone must point that... drop by drop.... trying to have more clever minds studying the subject.

As i told... IHF rules were crazy...and everybody was following....so.... we can go deep into crazy things, never criticising and the untrue turns true, and everybody enters the same boat and go inspecting the wrong thing.

Well... it is a very long way to go...but seed is planted and i will take care to put some water.

49 years reading US magazines, tests and evaluations based into numbers...and perceiving all that stuff as non sense... now a days...with internet... with forum...i can say that i disagree, that we need to study more psycho acoustic and reduce a little all that passion for numbers...to understand what happens inside a human beeing.... the real customer to amplifiers and speakers....not meters.

Alike worries about vibrations that can destroy some car when the engine reaches 12.000 RPM... when that motor,unders study and inspection cannot reach that RPM even without engaged...so....just academic brain exercise.

Reduce distortions from 0.1% to 0.008% is waste of time.... humans do not perceive... and speakers will produce enormous distortions that will turn the amplifier distortions almost nothing.

What represents a calculation error when you construct a road and discover was 10 centimeters longer into those last 50 kilometers.... when sun became hot.... the road will increase length by many meters because of heat!

regards,

Carlos

[PMA]

Both is important. I say 50% / 50%. People who only measure or people who only listen, both can remain in the vicious circle of same mistakes, routine and prejudice.

[destroyer X]

negotiator.... fifty fifty is fine..... and you are someone that design and produce precision instruments.... hard to you to think about that...i thank you by your attention in that thread..others will run from the thread and will say to themselves:

- "A hell to this idiot!"

But the best thing is to read, and to think about..and also to try to deenie my words, to reduce value and to point non sense things...this is evolution..because doing that, under the effort to show i am wrong, sometimes a ligth will appear into folks minds...when we try to find counter arguments to dennie something...many times... we realise the other guy is rigth..and this is evolution.

You was invited to inspect Symassym deeply...i have asked you to find for defects, for bugs..because someone doing that will discover, while listening and also while measuring, the amplifier quality.

So.... i am here to provocate... challenge may be better words in english...in portuguese is really provocation (provocação)..... the counter reaction will bring new ideas for sure.

Carlos

[jkeny]

To some extent I agree that 50-50 is the right balance but we have had amazingly accurate scientific measurements on audio now for what over 20 years but we have not made any discoveries as to what are the measures that determine a great sounding system. So my contention is that we have gone as far as we can go in this direction without some guidance as to where we should be focusing and this will come from psychoacoustics.

The real advances are to be found in understanding how we hear i.e. the brain-ear connection, psychoacoustics, whatever we want to call it. Once we get closer to that understanding we can then get closer to understanding how to build great sound reproduction systems.

[PMA]

More or less the same, I mean that careful listening may turn us to new methods of measurements of audio chain, regardless how difficult it is.

[ostripper]

By jkeny-The real advances are to be found in understanding how we hear i.e. the brain-ear connection, psychoacoustics, whatever we want to call it.

I think this describes the ASKA amps.. simple bootstrapped
"schoolbook"amps that sound better than 50 transistor
OEM's. "magic compensation" at work.
OS

[PMA]

I would warn against any "long distance" shared subjective experience. Nothing is as misleading as word description of sound. We need mutual experience at the same session. DIYaudio is great, it connects so many enthusiasts, on the other hand they have seldom an opportunity to listen together, and it is difficult to persuade someone in a 10 000 km distance about sound quality of a system he never heard.

[Rafael L]

Yes numbers indicate a bad amplifier

Ex:
DTH modifies the original wave, a note Do may sound like Do#
This can be measured or heard the sound.

IMD-Modulation between frequencies, the music will mix in complex passages(all instruments playing), effect not seen with a single instrument.
This can be measured or heard the sound.

Simply amps, are not stable with temperature and with the power, The damping factor change with the power, the bass are more loose.
This can be measured or heard the sound.

The loudspeaker are very important to appreciate good amplifier, Ex: a speaker rigid suspension and much heat in the whole magnetic a speaker has a lot of compression...

[Bigun]

Perhaps there are two groups of people, those who want amplifiers to be ideal - what goes in comes out unchanged but for being louder. And those who want their overall system to sound 'nice' whatever nice means.

back to photography for a second - people rate lenses on a subjective quality called 'bokeh' which deals with how an image looks in the out of focus areas. Sure it's possible to try and equate this with measurements of spherical aberration but by-and-by people prefer to describe it in words using terms like 'smooth' and 'harsh'. Even a 'bad' lens with a pleasing bokeh will be deemed a good lens by those who 'know'.

I think I'm more interested in amplifiers that are not ideal, there's no 'magic' in an ideal amplifier for me. Once you've made that leap, measurements of ideality are less helpful and we are back to the words 'liquid, tube-like' and the rest. I don't mind that one bit. It is a shame that some exploit the romantic side of audio with overpriced over hyped equipment.

[Bob Cordell]

Originally posted by Bigun
Perhaps there are two groups of people, those who want amplifiers to be ideal - what goes in comes out unchanged but for being louder. And those who want their overall system to sound 'nice' whatever nice means.

back to photography for a second - people rate lenses on a subjective quality called 'bokeh' which deals with how an image looks in the out of focus areas. Sure it's possible to try and equate this with measurements of spherical aberration but by-and-by people prefer to describe it in words using terms like 'smooth' and 'harsh'. Even a 'bad' lens with a pleasing bokeh will be deemed a good lens by those who 'know'.

I think I'm more interested in amplifiers that are not ideal, there's no 'magic' in an ideal amplifier for me. Once you've made that leap, measurements of ideality are less helpful and we are back to the words 'liquid, tube-like' and the rest. I don't mind that one bit. It is a shame that some exploit the romantic side of audio with overpriced over hyped equipment.

This is a very good way of putting it. If someone prefers an amplifier that alters the sound in a way that happens to be pleasing to them, more power to them. Some people describe this in terms like "expensive tone control". Hey, if it floats your boat....

The other group of people are philosophically inclined to amplifiers that are more true to their theoretical function - i.e., the straight wire with gain. For those peole, the tone control is a separate function (it may be their speakers, for example). Their view of a pair of "ideal" amplifiers might be two different ideal amplifiers that sound identical, even when the program material itself sounds harsh. They want the warts and all.

Another related thing to bear in mind here is the following question: With what amplifier did the loudspeaker designer voice his loudspeakers? If, for example, he voiced them with a soft-sounding tube amplifier with a modest dampling factor, the sound might be harsh with a solid state amplifier that is actually sonically more transparent.

Cheers,
Bob