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In Reply to: RE: I apologize for butting in posted by Ray Moth on December 04, 2014 at 13:40:40
Yes, I was waiting for him to bring up the old "wire is in the magnetic field" argument too...Maybe he has given up on that one (as I think he should!), and now it seems he just resorts to the argument that he leaves the internal wire alone because he can't get at it. Which leaves the question of why replacing two inches of the "inadequate" wire while leaving the other hundred feet or so of it intact is of any use at all. But I fear one cannot expect any science-based argument to be presented from that particular quarter...
Chris
Edits: 12/04/14Follow Ups:
I was part of a group buy from Electraprint a number of years ago and I bought two pairs of the groups' 3.8K primary transformers. One pair is set up like a normal transformer with lead-outs added on and the other pair have the magnet wire coming out directly from the windings. This pair were the prototype and apparently the only difference between them was the lead outs. The DCR is very close on all four transformers.
I still have both pairs but only made an amp with one set (300B SE). I think it would be educational to compare the two varieties and hear what if any difference the lead outs in identical transformers actually makes.
I'm sure I could rig something up to make them switchable in the same amp and get a better idea if there is a subjective difference.
Unfortunately, I sold my Altec 604-8G's last month so the comparison would be with a pair of Altec Model 19 instead. That might be an issue for JM but shouldn't be a show stopper.
There is more than enough well proven theory and practice over the past 100 years which proves there will be no audible difference.
What's the point of running through all this again. Why not focus your efforts on improving the performance by applying modern components and theory.
Do you honestly believe it took 100 years and a person with no background in electrical engineering to discover a 1amp rated choke requires 10awg leads?
Seriously!
No doubt science has made advances in the last 100 years, so why do we build amps with 1920's technology to listen to our music?
Because it sounds better?
Is there scientific proof that it does?
A SET amp or PP tube amp does indeed sound different than a modern solid state amp. Some people like that. It's also an awarding hobby to built vintage technology.
But a small power supply choke with generic 22awg leads sounds no different than the same butchered up with 10awg leads. So why bother.
An a part of building vintage technology is to preserve the find hand workmanship of that era. Looking into a replica amp and seeing transformers butchered up with gaffers tape and tyraps to no technical advantage insults this art.
And if education or adventure is ones goal, there is plenty of material on legitimate circuit modifications and topologies you can try. Why waste time on these silly tweaks that do nothing. Why not put that energy towards something that reaps rewards.
"Is there scientific proof that it does?"Yes.
Here's the short version;
"Norman Crowhurst wrote a fascinating analysis of feedback multiplying the order of harmonics, which has been reprinted in "Glass Audio," Vol 7-6, pp. 20 through 30. He starts with one tube generating only 2nd harmonic, adds a second tube in series (resulting in 2nd, 3rd, and 4th), and then makes the whole thing push-pull (resulting in 3rd, 5th, 7th, and 9th), and last but not least, adds feedback to the circuit, which creates a series of harmonics out to the 81st. All of this complexity from "ideal" tubes that only create 2nd harmonic!"
A single ended amp using a direct heated power triode with no feedback produces very little upper ordered HD. Upper ordered HD is what the human ear objects to.
Tre'
Have Fun and Enjoy the Music
"Still Working the Problem"
Edits: 12/05/14
Just to play the devil's advocate, how about designs like Doug Self's Blameless amplifier, which literally has almost no measureable distortion, and more or less ideal square wave response?
I appreciate that a perceptible amount of higher order harmonic distortion is going to be worse than a perceptible amount of lower order harmonic distortion, that point is proved beyond any doubt, and is not the subject of any argument.
However I would propose that when you compare an SET amplifier, with a THD in the 5% range to a solid state amplifier which has 1000 times less distortion, what really will explain the difference in perceived sound quality of the SET is the *presence* of distortion, not the absence of it. The higher order harmonics in the solid state amplifier may be present, but they are well below the noise floor of the SET amplifier.
+1
"However I would propose that when you compare an SET amplifier, with a THD in the 5% range to a solid state amplifier which has 1000 times less distortion, what really will explain the difference in perceived sound quality of the SET is the *presence* of distortion, not the absence of it. The higher order harmonics in the solid state amplifier may be present, but they are well below the noise floor of the SET amplifier."
I agree with you. And in any case, in its path from the microphones in the recording studio to the output of the home CD player, the audio signal will have gone through many stages of amplification using colossal amounts of negative feedback (not to mention huge lengths of "bad wire that can ruin the musical experience"!).
If a SET amplifier in the home stereo system really makes a big difference to the sound, it must be be because of distortion effects that it injects into the signal. The difference could not simply be explained on the basis that it was not injecting NFB-induced distortion products, given that the signal will already have been through so many previous steps using huge NFB.
Chris
Chris,
The link is the best little anecdote I've read about a smidge of second harmonic distortion in with your music.
Jamie
Big speakers and little amps blew my mind!
"The link is the best little anecdote I've read about a smidge of second harmonic distortion in with your music."Well, I don't have any problem with the claim that people, or at least some people, may find some added harmonic distortion to have a pleasing sound. That is really a psycho-acoustical question. It is essentially saying that they find the sound is better if it is put through a sort of "sound effects box." This is perfectly believable.
However, it is not the case that the distorting amplifier is restoring or recovering harmonics that were lost in the recording process. It is introducing some new sound effects that were not present in the original. And it is also introducing new kinds of distortion that were not present at all in the original concert-hall performance. For example, the harmonics that Benny Kim's Stradivarius produce do not result, in the concert hall, in intermodulation distortions amongst the sounds from all the other instruments that are playing. But the distorting amplifier, even if it is only contributing second-order distortion, is going to generate lots of intermodulation distortion products amongst all the sounds that it is reproducing.
Also, I didn't see any explanation in that little story about why the recording process was supposed to be preferentially suppressing the harmonics in the Stradivarius, while preserving the fundamental. However, the article claimed that "what we lose are subtle harmonics." I don't think there are "subtle harmonics" and "non-subtle harmonics." There is just an audio signal that can be decomposed in a Fourier analysis into a spectral distribution of frequencies.
In any case, if any "subtle harmonics" really are lost in the recording process, then they are lost. Period. Running the signal through a distorting amplifier is not going to succeed in subtlely restoring them again.
Chris
Edits: 12/05/14
I wouldn't advocate adding distortion but the best measuring amp is not always the best sounding one.
I'm probably gonna get flamed for this, but...
IMH and unlearned opinion a lot of it comes down to side-harmonics. Class AB amps somehow self-cancel the side harmonics, and thereby reduce the amount of musical information the ear/brain receives. They sure sound like they do. I believe class A amplifiers allow more of the input signal to be reproduced by the speakers, and the ear/brain is able to hear this, discern it, and add it to our muscial enjoyment.
I think a good analogy is MP3 vs WAV. The side-harmonics is exactly what the MP3 guts out of the music. Just throws it away. Anybody who isn't deaf can hear a WAV file sounds better than an MP3.
What I took away from the story was; The violinist thought his Stradavarious sounded more like a real violin on a SET amp, although it still didn't sound like a Stradavarious. Sometimes in life we just have to get by the best we can.
Jamie
Big speakers and little amps blew my mind!
Jamie, I remember reading an article in Stereo Review where one of the editors decided to learn how much distortion could be heard in 'real world' listening to music. He got some of his 'golden ear' buddies together for a listening test with a home system. I don't remember all the particulars, but what stuck with me was the conclusion. All of these expert listeners couldn't hear distortion until it was well within single digit and/or double digit distortion. I haven't thought twice about measured distortion since. I started looking at things differently and ran across an obscure company named Electronic Tonalities.
If second order distortion has me listening to music for hours and wanting more. as apposed to a clean amp that has me fatigued after an hour or so, I'm all for the distortion.
How's that amp build coming along?
"The violinist thought his Stradavarious sounded more like a real violin on a SET amp, although it still didn't sound like a Stradavarious. "Where, in the story below, does it say the Benny listened to a recording of his violin? It doesn't, it said the police had him listen to his violin. We have to assume the police had a different violin player come down to the police station and play different violins, including Benny's and Benny, even though he was blindfolded, picked his violin.
*The police after finding the Stradivarius violin back wants to be sure that it really is the correct violin of Benny Kim, so they blindfold him and make him listen to a number of different violins at the police station, can he recognise his violin ?
Probably yes, for a trained ear it should be easy, but Benny is sitting in a police office and is under stress and not in his familiar surroundings (conservatorium or practising room ) and still he probably manages to recognise his violin.*"IMH and unlearned opinion a lot of it comes down to side-harmonics. Class AB amps somehow self-cancel the side harmonics, and thereby reduce the amount of musical information the ear/brain receives."
By "Class AB amps" I am assuming you mean push pull amplifiers running in Class AB?
A push pull amplifier will cancel even ordered harmonics that are created in the push pull part of the circuit. Even ordered harmonics that are part of the input signal, as well as anything else that is part of the input signal, are not canceled by the push pull circuit, just the even ordered harmonic distortion that is created by the push pull circuit itself.
"I think a good analogy is MP3 vs WAV. The side-harmonics is exactly what the MP3 guts out of the music. Just throws it away. Anybody who isn't deaf can hear a WAV file sounds better than an MP3."
I agree with the last sentence but the parts of the music that are intentionally thrown away as part of the process of making a MP3 has nothing to do with push pull circuits and the canceling of even ordered harmonic distortion. Not even close, so it's not a good analogy at all.
Tre'
Have Fun and Enjoy the Music
"Still Working the Problem"
Edits: 12/06/14
"A push pull amplifier will cancel even ordered harmonics that are created in the push pull part of the circuit. Even ordered harmonics that are part of the input signal, as well as anything else that is part of the input signal, are not canceled by the push pull circuit, just the even ordered harmonic distortion that is created by the push pull circuit itself."
That's what they say. I'm not so convinced. You may be. There seems to be something going on with PP amps that don't meet the ear. I have a feeling our ability to really test what is going on is rather more limited than some people imagine.
Carry on.
Jamie
Big speakers and little amps blew my mind!
"There seems to be something going on with PP amps that don't meet the ear."Yes, I explained that in my first post.
Push pull creates odd ordered (the very kind of distortion that humans find objectionable) harmonic distortion.
Did you read the linked Lynn Olson page?
Tre'
Have Fun and Enjoy the Music
"Still Working the Problem"
Edits: 12/06/14
"Push pull creates even ordered (the very kind of distortion that humans find objectionable) harmonic distortion."
No it doesn't. I produces higher odd order harmonics. So you are wrong Tre' How about that?
I have read all the Lynn Olson I could get my hands on many times.
Now I want you to say you are wrong. Even if you explain it as a misprint. LOL
Jamie
Big speakers and little amps blew my mind!
You will find that when I'm wrong about something I have no problem admitting it.Tre'
Have Fun and Enjoy the Music
"Still Working the Problem"
Edits: 12/06/14
"You will find that when I'm wrong about something I have no problem admitting it."
You didn't admit you were wrong in this case. You explained it. You said you were sorry, but you didn't admit you were wrong.
I have learned quickly on this forum that a typo, or simple mistatement can have the Accuracy Gestapo on you in a heartbeat. I won't report you to them.
Jamie
Big speakers and little amps blew my mind!
"I won't report you to them."Thanks Man! :-)
And no, I didn't admit that I was wrong. In this case, I just mis-typed.
But when I'm proven wrong, and that has happened many times, I do admit it.
I'm not near as stubborn as it may seem.
Tre'
Have Fun and Enjoy the Music
"Still Working the Problem"
Edits: 12/06/14
"Thanks Man! :-)"
No Problem! ;)
Jamie
Big speakers and little amps blew my mind!
.
Have Fun and Enjoy the Music
"Still Working the Problem"
It was just an interesting little story. I don't like "effects boxes." And I think the old research said the human ear couldn't pick out 4% added second harmonic distortion, so I think it's a bit of a red herring. I think well designed SET amps can be held to 4% second harmonic distortion.
Jamie
Big speakers and little amps blew my mind!
If I have the time and already have the parts on hand, why do you care?
Caution Kyle,
No telling how good the stock lead out wire is !!!!! Have fun. The trannies have to break in 200 hours.
I've done this on Hammond Ef XFRs to DHTs starting back in 2007 as I recall.
I "giggle" when these guys are so wrong. The bigger the EE degree, the worse the mind is open to new possibilities. Sad, sad. NONE of them would think to simply try it out and find out for themselves...ohhh no !!
Jeff Medwin
That makes no sense at all if you stop to consider that statement.The EE has at least a four year education past high school. True EE programs vs the newer ET programs still require substantial credits in liberal arts. History, philosophy, language - just check and university degree outline.
On the strict technical side, the EE has studied many engineering theories, not just electrical but basic engineering principles that cover all engineering disciplines. Did you ever look at the study guide of a PE test? The FE exam (the first step) is universal for any PE license, the same for electrical, mechanical, civil. That's because true engineering has common ties within mathematics.
Any engineering curriculum requires work. It's not some degree program you can just BS through like a degree in "fine arts".
Now how is that "closed minded"?
Let's look at the weekend hobbyist such as you who refuses to acknowledge proven and tested theories. Eschews any attempt to test and qualify claims they make. States things like audio is extreme bandwidth which no modern test equipment can measure.
Now that sounds very "closed minded" in my book!
Edits: 12/05/14
Unfortunately I have to take Jeff's side on this one. I did engineering and engineering related work for 27 years and while I have moved on to another field, it doesn't mean I don't remember the practical aspects.
My experience taught me that just because a person has the education and has worked in a capacity for a period of time doesn't make him the equal of all in that area of expertise. Engineers are like anyone else, there are great ones and sh*tty ones. More sh*tty than great in my experience.
I worked with a lot of engineers over the years that weren't worth a damn in practical matters. They could spout off endless calculations and what their profs told them were best practices but when it came down to the actual project decisions they were at a loss. This is in industries as diverse as robotics, aircraft design, underground mining vehicles and refineries. There is just no substitute for experience and if you think that's not the case, you're likely a pencil pushing desk jockey with no real practical experience.
So, bottom line, while I disagree with Jeff most of the time I also appreciate his 30 plus years of actually making amplifiers. Lots of them. I read about his projects in Sound Practices in the 90's and they weren't my style then or now but I give credit where it's due. He's done the real work to have an opinion and I'll support his right to have that opinion.
I certainly think that many posters here haven't got the hours in with a soldering iron to challenge what he thinks he hears and are just reciting Crowhurst or Jones or whoever they relate to. While I'm a bit short of Jeff's hours, I have made a large number of amps and preamps of a wide variety of designs and not all of them sucked. Many of them would be ridiculed by the so called experts here because I didn't follow your idol's path. I'm good with that. You should be too.
I know exactly the class of engineer you are referring to. Bookworms that can recite the most complex formulas but can't solder on a RCA connector. Then there are just plain incompetent engineers that can't do the theory or practical right.Then we also have the non degreed engineers that can run rings around the group. I know many of these types too and they are all very successful.
Myself, I am hardly an engineering scholar, I am not a born student at all. But I have been building electronic projects since I was about 9 years old, that would be 1969. I built a B&W TV camera from raw parts in my junior high school year when I was given an old vidicon tube. I made it color in my senior year when I got another one tube and deflection coil and with the help of the defunct Edmund Scientific made a red/cyan optical system.
But after entering Drexel in the late 70s, and that camera project got me in by the way, not my pitiful SATs, I soon learned how it worked in great detail and why many things I "TRIED" did not. At 54 years old I have built thousands of personal projects as well and many commercial projects and products in the broadcast television industry.
So you can see I for one am not impressed with JM's meger project history. For all that time he has advanced very little in understanding how this stuff works. And for him to insult the the industry professionals as a whole is what labels him an idiot!
Edits: 12/06/14
"I certainly think that many posters here haven't got the hours in with a soldering iron to challenge what he thinks he hears..."
That is the problem. I'm sure he sincerely thinks he hears the effects of his choke mutilations. Just like the people on the Tweaker's Forum sincerely think they hear the effects of the crystals in the room, or the flashings LEDs, or the quantum fuses. It is all delusional.
Chris
Esse Est Percepi.
Jeff Medwin
Jeff, there is no doubt you have many years of building experience which few others can legitimately challenge. If one of us wanted something built and could afford to pay an expert to do it, I'm sure you would be a safe bet (provided that you were prepared to undertake the work). Some EEs, professionally qualified or otherwise, would not have the skills, experience, enthusiasm or understanding to be able to match your ability. You have also often given generous assistance to others and helped them achieve what they aimed for.
However, there are many EEs in this forum, both formally qualified and otherwise, who do understand what is going on -- because of their education, training and experience, not in spite of it -- and are very well able to contribute far more than most here. These members of AA, some of whom you know, deserve our credit and respect. They are far from being closed-minded and to dismiss them with such silly phrases is unprofessional, unfair and just plain wrong.
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