The Sound of Science

tlf9999

Disabled Account
2005-05-25 2:25 am
none
or is it the science of sound? or the art of sound?

I was browsing the chip forum, and noticed that many now consider the inverting topology that much superior to the non-inverting topology, based on multiple sound (pun not intended) theories and personal testimonies from trusted forum members.

But if you go back a little bit, you will see that not too long ago, the non-inverting topology was all the rage, based also on sound theories and personal testimonies from equally trusted forum members who have listened to both topologies.

this reminded me of my experience with audio. When I first started in audio, the williamson's amp was all the rage, countless people (DIY and commercial) raged on as to how the transformerless and PP topology of the Williamson's were that much superior to the SET and how they felt a huge improvement in sound quality after going to the Williamson's.

Then, it was the age of transistors. first people loved the sound of germanium SET amps. that was replaced by the "far superior" germanium Class AB PP transformer-coupled amps. Then OTL came alone, and people were in love with them, due to their "far superior" sound quality (no transformers!). Only to be toppled by the "far superior" OCL.

Soon after that, we got MOSFETs because of their supposedly "tube" sound that bipolars couldn't provide - wait, didn't we just say that transistors were that superior to tubes?

And then we saw people coming out stating how superior the bipolar sound over the MOSFETs (?). We did take a detour in the IGBT and chip amp land but that didn't take too long to get back.

Now, you hear people talking about how much better tubes sound, or transformers sound, or carbon film resistors sound; how much tantalum caps suck (they were once thought to be the king of audio, remember?), or polyester caps suck (they almost took out those "bad" sounding oil paper caps, remember?).

The point I want to make is that our perception of sound is much like our perception of fashion: too many of us just don't know the good from the bad, in spite of our firm believe that we do.

So when someone tells you next time A sound so much better, take that with a huge grain of salt. Because chances are that person don't have the slightest clue what he is talking about.
 
This is interesting! You might be starting a fight!

But it is good to put things in perspective. I got back into diy audio a few years ago, starting with National chip amps, and ending up with tubes and mosfets. And I remember how transitors were supposed to last forever and sound better through direct coupling. Now I know better than to believe all that.

My experience is that they can all sound good, but in different ways. My LM3886 amp sounds very clean and detailed, but compared to my triode amp, it sounds rather dry and lifeless. The tube amp has a warm lively sound, but may be rather "colored" compared to the more "analytical" chip.

Which is more "accurate"? I have no idea! Maybe it's more a matter of taste. I like my tube amp, but I have also heard transistor amps that I could be just as happy with. I am still looking for my ideal amp..... and that's the fun of this hobby.

At this point, I don't think there is a "best". Just lots of interesting paths to take.....

Kent
 

anatech

Administrator
Paid Member
2004-06-06 8:31 pm
Georgetown, On
Hi tlf9999,

Thank you! I couldn't have said it better myself. Over 25 yrs of observing people and their audio components prove you correct.

I can't tell you how many audiophiles have come in wanting an upgrade ("the unit sounds great, I want to make it better"). Setting the unit up on the bench then shows actual problems, and no, it didn't measure to spec either. The customer was always surprised. Hmmmm

-Chris
 
Audio is subject to the very same fad and fashion which besets most other consumer arenas. Some even formalize it by calling it Fashion.

This is normal behaviour for the human being, and merely reflects two facts: that the wisdom of the parents is not transferred to the offspring at birth, and that human beings are herd animals, unself-consciously seeking the approbation of those around them.

Cheers,

Hugh
 
hi tlf9999

absolute phase means that the sound comimg from the microphone is in phase with the sound from the speaker

in an ideal HiFi system the non-inverting topology is prefered
over anything else and it is the one used in most descrete
form amplifier topologies

"or is it the science of sound? or the art of sound?"

in my opinion science becomes art when its sound is also judged
by subjectivism which in other words means art of sound just
as a painting is mostly judged by vision

"The point I want to make is that our perception of sound is much like our perception of fashion"

this could be the case, perception is an individual thing especially
when ears behave like mics of different specs

"Soon after that, we got MOSFETs because of their supposedly "tube" sound that bipolars couldn't provide - wait, didn't we just say that transistors were that superior to tubes?"

in my opinion it is not a device issue but rather a circuit issue
there is however advantages over devices with certain circuit
topologies

"So when someone tells you next time A sound so much better, take that with a huge grain of salt. Because chances are that person don't have the slightest clue what he is talking about"

as ive said before it all comes down to what their ears tell them what to talk about that doesnt mean they dont know what they talk about

nice thread!

cheers
 

anatech

Administrator
Paid Member
2004-06-06 8:31 pm
Georgetown, On
Hi mastertech,
If I hear something reproduced exactly as I heard it live, there is absolute fidelity there. Same goes for everyone, no matter what their hearing is like. So that cancels out. Hearing loss can mask a non-perfect reproduction but that's it.

Phase? What is the correct phase after it goes through the outboard gear and mixer + tape decks in a studio? That's a crap shoot. Some amps are inverting, some speakers are reverse phase to the norm. Some cables are miswired. Happens.

People each can deal with some shortcomings and not others. That's called taste I guess. As the system becomes more accurate, the more people tend to agree on those systems - in general (on average).

No one likes to appear less knowledgeable than others. It only takes one self proclaimed expert to start a "fad" - misinformation. People trying to learn will pick this up.

Salesmen and manufacturers use this to sell useless items to the public. Good money wasted for greed and or stupidity. May as well be tonic.- (cures all don't ya know) And many people haven't any clue what they are talking about, but they do like to talk. Those people will defend their point of view to the death, as in "all I know is what I heard (insert saw). The same goes for people with "special powers".
I wish physiology didn't come into it, but that's where we get into trouble. A young child is an excellent defence here.

-Chris
 
When we make choices based on sound differences that we think we can perceive but we actually cannot, those choices are always random or not related to sound at all (they may be based on any other criteria like shapes, colours, materials, names, finishings, prices, smells, etc...)

This explains the evolution of past and current audio fashion and market trends quite well. Indeed there is a strong random and non audio-related component.

I've even seen a website demonstrating that blind A/B tests render 50% / 50% results (purely randum) when similar enough equipment and a high enough number of listeners is employed. This is the same statistic result you get when you throw a money a high enough number of times.

Have you ever heard about Synesthesia? It is a well known neurologic phenomena involving unconscious cross-talk between different senses and it's well documented on medical literature.
http://web.mit.edu/synesthesia/www/synesthesia.html

Try google for more links. Note that it's also sometimes misspelled as 'Synestesia' or 'Sinestesia'.
http://www.hyperogga.com/synesthesia.asp


I remember that decent trebble at moderate volumes made me feel cold back when I was in my teens and got my first pair of decent-sounding speakers. It was obviously a new stimuli that my brain was misunderstanding. In fact, I no longer have that ability.

Actually synesthesia is a natural stage of child brain develompent, we all have gone through it in the first few years of life and a small amount of it remains in most adults.
 
Brain adjust everything, so, many times, the decision of good or bad

Depends your own decision.... everything is brain processed.

As images, from movies, flicking and we do not see them flicking, because light persistence phenomena of our eyes/brain.

Also, try to look down.... the nose will be blocking.... brain re-compose the image to you, and your nose do not appear in the image perceived.... Brain make that.... you see one illusion, not the real image.... and the audio?

We can listen music, produced by our brain (memory), and no music playing, when we are feeling deep love...and no music is playing...brain produce music, play it using memory....many guys that really had strong passions can say that.

So...there are many subjective things to study, because we can hear 3 db of power changes.... so.... 100 watts and 150 watts are the same for us.... that difference has no meaning, only numbers, we do not perceive nothing!

0.001 and 0.01% of distortion sounds the same for humans, i believe the scopes can be happy, distortion analisers can feel very good, and i believe spectrum analisers will smile a lot.

But you will not see those equipments going shopping audio appliances....so, do not make sense construct amplifiers having too much worries about some distortion reduction from 0.01 to 0.001, as speakers, by itself already distorted 1 percent or more...so...good to see Eva studying Human perception, i really think this is a need to Enginnering College.

To invert the phase, you can check.... stay up side down and listen to the music..... and tell us if you perceive some....yes, you perceive.... your home furnitures will appear inverted!

regards,

Carlos
 

tlf9999

Disabled Account
2005-05-25 2:25 am
none
Eva said:
When we make choices based on sound differences that we think we can perceive but we actually cannot, those choices are always random or not related to sound at all


that is so accurate. People, including some of us here, are so intereted in appearing knowledgeable and expert-like sometimes they will invent impossible tales or buy into impossible tales just to conform with the "experts", aka herd behavior.

I guess it is not a bad thing to part those people from their hard-earned money, :)
 

Greg Erskine

Member
Paid Member
2002-01-05 11:56 pm
Sydney
tlf9999 said:
that is so accurate. People, including some of us here, are so intereted in appearing knowledgeable and expert-like sometimes they will invent impossible tales or buy into impossible tales just to conform with the "experts", aka herd behavior.

I guess it is not a bad thing to part those people from their hard-earned money, :)

tlf9999,

This is my opinion and I offer it for others to consider.

There is no absolute truth in audio or anything for that matter. It is all a matter of one's perception of reality. This is why there are so many different and changing "right" answers. You have to choose which is right for you. People kindly offer their version of the correct answer and it is up to us as individuals to either accept or reject their advice. If we decide to reject some advice, it doesn't automatically mean it was wrong, just it didn't suit our situation, preference or understanding.

I choose to appreciate everyone's opinion and select what fits with my situation or perception. I get a lot of enjoyment and happiness by doing this. Everyone has something to offer and I don't see people as idiots or a sheep to fleece.

I like to try to treat everyone with respect and understand that while poeple may have a fundamentally difference of opinion they are not necessarily wrong.

It is human nature to try and fit in with a herd, this is a automatic survival instinct. The size of the herd does vary. Many find this a great source of happiness.

There is nothing wrong with handing over large amounts of cash for the latest and greatest if you personally achieve happiness and enjoyment by doing so. It doesn't matter that I could never do this but I can appreciate other can.

What is not right is when one doesn't just offer their opinion but tries to force their opinion on others as the only right answer. (Did I just contradict myself, oh.. doesn't matter) :D

Regards
 

anatech

Administrator
Paid Member
2004-06-06 8:31 pm
Georgetown, On
Hi
SY, of course you are correct, but I didn't want to get into that argument. Phase is just such a mess so as to make polarity a moot point. I'm in total agreement with you.

Eva is explaining the why with humans, and probably dogs as well. -I will read the links, thank you.

Carlos is reminding the number chasers about reality. But the final engineering is about accounting, I think all manufacturers and designers will agree with that (you have to be able to sell it, right?).

Greg, after many years as an audio salesman, yes. You have to sell something to put food on the table. I have to "sell" something real to consumers. Not green markers for CD's (loved that one - green LED's now), power cords, bricks (magic ones), on and on. I sell good service work grounded in reality. I think it is very important not to purposely mis-guide our customers. If we do, we all lose in the end. Good business practices would do the industry a lot of good in the long run. I do not believe the audio industry is being remotely responsible in it's activities. Now we have RoHS to deal with.

I think we are all agreeing with tlf9999. Besides, we have enough real experts on this forum to consult with. I learn every day.

-Chris
 
About absolute phase:
Obviously absolute phase in itself doesnt matter, but who knows electronically is does matter indeed...
For example: in a CommonEmitter configuration therefore is the Miller Cap so considerable.
(maybe the junctions, parasitic caps, etc do they job here...)
A CommonBase stage doesnt invert, and it is much faster, but has a low input impedance,
and doesnt amplify the current.
And the CommonCollcetor is the reverse, it amplifies only the current, etc...
What would happen, when we amplify our sign across two stage:
a CB should amplify the voltage, and a CC the current, instead of
the general LTP. (Note: this would look like similar to a diff-amp)
And now our amplifier (both CB & CC) has an absolute phase...
A DC (an absolute phase) amplifier like this, interest me long
time ago, so i'am curios to your comments on this idea !!!
(I know that the cascode configuration already exists!)
 

Cortez

Member
2002-12-26 9:45 am
Hungary
Yes, thats maybe true, but temporarily, let's aside from that by
the first time, and lets suppose that it somehow has a much
better audio quality. If yes, what would happen when we cancel
this direction cause of offset... :eek: We should be much more
carefull with throwing solutions away ! Think every time that
this would be the best soultion ever seen... :D
(Maybe a DC servo should solve the DC problem, let's go further.)
 
anli said:
I have tried to inspire the forum members to discuss a very close theme:

http://www.diyaudio.com/forums/showthread.php?s=&threadid=62150

As you can see, I was not lucky there :(


I think I know why you didn't succeed... You asked for evidence to support claims. Things that could be measured and reprocuced accurately. Measurements and hi-end gear don't mix. ;)
As someone already insinuated, people will tell you that there are factors that just can't be measured. If they could (or people started to agree that every property of audio gear can be measured), the magic would go away.

Not that you'd ever get to the perfect amplifier. The components aren't ideal, and this influences on the result, so for every manufacturer, be it DIY or commercial, there are compromises. This is what "taste" is all about. Finding the compromise you (or your ears) prefer.

Just my 2 cents
Jennice
 
"Measurements and hi-end gear don't mix. "

Now that's PURE marketing. First destabilise the buyer's perceptions then sell them MORE than they need because they are willing to spend! Once you have convinced them that measurements are meaningless you can convince them of your 'black art' abilities - and flog them any overbuilt c*ap! From 2KW power supplies to simplistic concepts with flair! Anything that blights the planets resources to excess, it seems, has to be a worthwhile goal! Can mostly only be judged by the amount of power it consooms and almost uniquely US - surprise, surprise!

Beneficial mostly to the purveyors bank account. Buyers convince themselves it sounds good because they don't want to accept they've been severely ripped off.

Cheers,
Greg