I agree with Fred's comments about self-confessed "experts". And I agree with Self that there is nothing magic about his approach to amplifier design. And I will expose myself to sniper fire by saying I think it is the lack of anything special in Self's approach that is the reason he doesn't have anything to contribute in the marketplace.
There are holes in the hifi market. There always will be. There is the always present price/performance chase and there are specific holes like the need for an amp that rocks like a Naim and images like a Krell.
The people who know what they are doing almost never publish, not even in AES Journal nor in patents. Plenty of people who don't know what they are doing publish volumes. This makes things very confusing for the uninitiated reader. As Fred said earlier, everything is questionable. The fun is still in the chase
"The people who know what they are doing almost never publish, not even in AES Journal nor in patents. Plenty of people who don't know what they are doing publish volumes. This makes things very confusing for the uninitiated reader. As Fred said earlier, everything is questionable."
I once pulled back a telecom patent application because I was unhappy with the circuit It worked and looked liked a valid thing to patent but I didn't think it worked well enough. My coworkers and company patent attorny had a fit and called me an idiot.
I once pulled back a telecom patent application because I was unhappy with the circuit It worked and looked liked a valid thing to patent but I didn't think it worked well enough. My coworkers and company patent attorny had a fit and called me an idiot.
Re: Re: power to the people please
I know you must be pulling my leg now. I wish I could write such bold and vivid satire. I am laughing so hard I can hardly type!
Good one! Obviously a payback for the commom sense crack.
To inspire you for your next whooper, I don't think thats even related to common sense by marriage. Line conditioners were not even orginally designed for audio. I guess you have never seen noise on your TV from RFI on the AC! Stop it, you making me hurt from laughing!!!
nw_avphile said:
I know you must be pulling my leg now. I wish I could write such bold and vivid satire. I am laughing so hard I can hardly type!
Good one! Obviously a payback for the commom sense crack.
To inspire you for your next whooper, I don't think thats even related to common sense by marriage. Line conditioners were not even orginally designed for audio. I guess you have never seen noise on your TV from RFI on the AC! Stop it, you making me hurt from laughing!!!
Re: Re: Re: power to the people please
If you have credible, objective, pertinent issues with what I posted above, I'll try to respond to them. Otherwise, it would seem you're back to attacking me to apparently avoid addressing any of the real issues here?
This forum is called diyAUDIO isn't it? I'm not talking about the use of conditioners for TV or other purposes. TV's used to get their sync signals from the raw AC line. So line noise tended to make all sorts of weird things happen. But that has about as much to do with this discussion as birds flying south for the winter.Fred Dieckmann said:
If you have credible, objective, pertinent issues with what I posted above, I'll try to respond to them. Otherwise, it would seem you're back to attacking me to apparently avoid addressing any of the real issues here?
I'll do it for him:
How To Design a High End Amp (Tube Version)
1. Find a schematic from the 1950s; the Eico HF87 is a good start, being the basis for amps from Conrad-Johnson and VTL.
2. Determine what name-brand parts and wires are in fashion.
3. Have Peter design and fabricate your metal work (I'm frankly in awe of his abilities).
4. Make the unit with the fashion parts, price it at $10K.
5. Have a bunch of poetic hype ready for your conversation with the Stereophile reviewer.
How To Design a High End Amp (Tube Version)
1. Find a schematic from the 1950s; the Eico HF87 is a good start, being the basis for amps from Conrad-Johnson and VTL.
2. Determine what name-brand parts and wires are in fashion.
3. Have Peter design and fabricate your metal work (I'm frankly in awe of his abilities).
4. Make the unit with the fashion parts, price it at $10K.
5. Have a bunch of poetic hype ready for your conversation with the Stereophile reviewer.
Pmkap
Pmkap....i have studied this particular chip's schematic with some rigour......it is infact a widlar-thomson derivative....i.e: the same topology in essence recommended by D. Self...my point is, differentiating between topologies by merely listening to them is shown to be fraudulent by the D.Self/gainclone debate on this forum...
Some rigor......
No...pmkap......i refuse to discuss corpses here...
Evidently a quasi-complementry output stage is equivalent to a compementry EF of CFP within the context of your rigorous study....
Actually my dear fellow, i have nil difficulty in distinguishing between these most elementary of SEPP arrangements.....
Both the National LM and Signetics TDA72xx are quasi-complementry output configurations, possibly due to the difficulty of putting complementry output devices of sufficient power in a monolithic circut. That toplogy is not something I've not seen in Mr. Self's work.
...you appear to have only a cursory appreciation of Self's material, which is quite detailed in its discussion of all three output stage topologies used in the context of the Thomson-Widler voltage gain block...
Indeed, most amps use a ltp input, a Vas, a Vge, and an ouput stage in an amp; and if by your understanding that makes them equivalent topologies I'll accept that as consistent with your intellectual acumen. In the scheme of things, certainly, most all AB audio amps 'look' like Bob Widlar's op amps.....
........No......dear...dear.....dear...fellow.......most amps. do not 'use a VAS'.....as suggested by you or indeed, Self...this would imply the local application of shunt (voltage) derived, series (voltage) applied negative feedback.......
The second stage is, strictly speaking, a T.I.S, (transimpedance stage), courtesy of the local shunt (voltage) derived, shunt (current) applied negative feedback implemented by the Miller stabilising capacitor. I trust you are with me thus far...
I would never argue that one can differentiate between amps toplogies (by whatever metrics) by only listening. I will say that after using 'engineering' to ensure stability, bw, slew.... one can differentiate between implementations by listening......
If you cannot distinguish subjectively between 2 amps of similar objective metrics, good for you, you can save yourself some money, but please don't try to justify yourself with specious topological equivalencies.
I fear you misunderstand.......i strongly assert that infact anyone can hear the difference between two amplifiers with different power ratings and current delivery, ounce such worthies are afforded the opportunity to twiddle the volume control....that is elementary...
However, i reiterate,....it has been shown to be impossible to distinguish between units of whatever topological provenance, provided such posses THD+N, (across the audio band), below 1000 ppm, (Prof. Cheery suggests <33000ppm!), when driven in turn, into the same set of speakers, at the same voltage swing across the later, and well within the power ratings of the units.
As for 'specious (sic) topological equivalencies'...nothing further need be said...
Pmkap....i have studied this particular chip's schematic with some rigour......it is infact a widlar-thomson derivative....i.e: the same topology in essence recommended by D. Self...my point is, differentiating between topologies by merely listening to them is shown to be fraudulent by the D.Self/gainclone debate on this forum...
Some rigor......
No...pmkap......i refuse to discuss corpses here...
Evidently a quasi-complementry output stage is equivalent to a compementry EF of CFP within the context of your rigorous study....
Actually my dear fellow, i have nil difficulty in distinguishing between these most elementary of SEPP arrangements.....
Both the National LM and Signetics TDA72xx are quasi-complementry output configurations, possibly due to the difficulty of putting complementry output devices of sufficient power in a monolithic circut. That toplogy is not something I've not seen in Mr. Self's work.
...you appear to have only a cursory appreciation of Self's material, which is quite detailed in its discussion of all three output stage topologies used in the context of the Thomson-Widler voltage gain block...
Indeed, most amps use a ltp input, a Vas, a Vge, and an ouput stage in an amp; and if by your understanding that makes them equivalent topologies I'll accept that as consistent with your intellectual acumen. In the scheme of things, certainly, most all AB audio amps 'look' like Bob Widlar's op amps.....
........No......dear...dear.....dear...fellow....
...most amps. do not 'use a VAS'.....as suggested by you or indeed, Self...this would imply the local application of shunt (voltage) derived, series (voltage) applied negative feedback.......The second stage is, strictly speaking, a T.I.S, (transimpedance stage), courtesy of the local shunt (voltage) derived, shunt (current) applied negative feedback implemented by the Miller stabilising capacitor. I trust you are with me thus far...
I would never argue that one can differentiate between amps toplogies (by whatever metrics) by only listening. I will say that after using 'engineering' to ensure stability, bw, slew.... one can differentiate between implementations by listening......
If you cannot distinguish subjectively between 2 amps of similar objective metrics, good for you, you can save yourself some money, but please don't try to justify yourself with specious topological equivalencies.
I fear you misunderstand.......i strongly assert that infact anyone can hear the difference between two amplifiers with different power ratings and current delivery, ounce such worthies are afforded the opportunity to twiddle the volume control....that is elementary...
However, i reiterate,....it has been shown to be impossible to distinguish between units of whatever topological provenance, provided such posses THD+N, (across the audio band), below 1000 ppm, (Prof. Cheery suggests <33000ppm!), when driven in turn, into the same set of speakers, at the same voltage swing across the later, and well within the power ratings of the units.
As for 'specious (sic) topological equivalencies'...nothing further need be said...
DUMMIES ABOUND.
Hi,
This is sooo unfair...Peter never did anything but show his work to the public and as far as I know he's only building some for friends and doesn't even have a company established yet.
Moreover it's not even relevant.
There are a lot of members involved in the commerce of selling/building audio stuff, myself included although not actively anymore.
For all the time I have been a member here I've never seen any of them push their product, if anything the forum just served as a platform for exchange of information, most of the time at the request of fellow members.
If I was a mod here you'd be sinbinned for remarks like that.
In case you ran of of arguments for the rest of your poor attempts defending something entirely defenseless than try to refrain from cheap shots.
You definetily come across as a poor individual.
Cheers,
Hi,
This is sooo unfair...Peter never did anything but show his work to the public and as far as I know he's only building some for friends and doesn't even have a company established yet.
Moreover it's not even relevant.
There are a lot of members involved in the commerce of selling/building audio stuff, myself included although not actively anymore.
For all the time I have been a member here I've never seen any of them push their product, if anything the forum just served as a platform for exchange of information, most of the time at the request of fellow members.
If I was a mod here you'd be sinbinned for remarks like that.
In case you ran of of arguments for the rest of your poor attempts defending something entirely defenseless than try to refrain from cheap shots.
You definetily come across as a poor individual.
Cheers,
Re: DUMMIES ABOUND.
And if the "something entirely defenseless" is the Hafler test that Tube_Dude has been discussing, you're wrong. Its very defensible. In fact, it's SO defensible that nobody here has yet come up with any credible reasons why it's not an extremely accurate indicator of real-world amplifier performance.
The null difference test was first proposed (that I know of) by Baxandall in 1977 and so far I've yet to see its validity disputed by any objective means. If you have some objective reason why it's a bad test, please share it with us.
Cheap shots like the one you made at me in this thread? Shall I quote you?fdegrove said:Hi,
In case you ran of of arguments for the rest of your poor attempts defending something entirely defenseless than try to refrain from cheap shots.
You definetily come across as a poor individual.
And if the "something entirely defenseless" is the Hafler test that Tube_Dude has been discussing, you're wrong. Its very defensible. In fact, it's SO defensible that nobody here has yet come up with any credible reasons why it's not an extremely accurate indicator of real-world amplifier performance.
The null difference test was first proposed (that I know of) by Baxandall in 1977 and so far I've yet to see its validity disputed by any objective means. If you have some objective reason why it's a bad test, please share it with us.
Re: The menace!!!!...reprise...
Much as he might wish to sinbin people, Frank can't!
However, Jorge, I would personally appreciate it if you read a little of the background of others contributions to the forum before criticising them.
Everyone- can we keep this thread on the intellectual high ground please, this is one of the most interesting topics in a long while, I'd hate to see it falling apart now.
Tube_Dude said:
Is the second time that you came with this menace...want put me in sinbin...do it....here i am...
"Nothing fears the stronger... not even the death!!!"
Zeca Afonso (Portuguese Poet)
Cheers
Ps
Yes...the oposite of you....the true" rich individual"!!!!!
Much as he might wish to sinbin people, Frank can't!
However, Jorge, I would personally appreciate it if you read a little of the background of others contributions to the forum before criticising them.
Everyone- can we keep this thread on the intellectual high ground please, this is one of the most interesting topics in a long while, I'd hate to see it falling apart now.
HA...
Hi,
The wonderful Wondercaps...
That goes to show how little value the test method you are defending really has.
If you can't discern the definitely present colourations in these caps than I just wonder where you're heading in your quest for better audio.
Conversely, if you're dimissing the value of any "boutique' parts based on your assesment of the sound of these caps I can fully understand that too.
See?
Hi,
The wonderful Wondercaps...
That goes to show how little value the test method you are defending really has.
If you can't discern the definitely present colourations in these caps than I just wonder where you're heading in your quest for better audio.
Conversely, if you're dimissing the value of any "boutique' parts based on your assesment of the sound of these caps I can fully understand that too.
See?
Re: The power of publicity....
If I have managed to have a product like that, it's only because I'm spending countless hours on this forum. So far, I didn't sell a single unit yet and I just thought that it might be nice to show my first real world product to fellow members. Actually, I went so far as to show the inside of the product as well which is rather an act of a good will on my part, since because of simplicity of a design, anybody can copy it. I also never protected the secret of parts I'm using as some other makers do.
So it was actually a bit of disappointment to see it was greeted with a hostile response from some members under a false premise that I try to advertise it here. I don't think of selling it here on a forum, because most of you can build it yourself and for rest it's still unobtainium, since the price tag is more than $1000. My Zen amp didn't sell at $500, so I don't have any delusions to sell Gainclone at $1500.
The product will be marketed through regular channels and I don't care much who's buying it. I'm also too busy building it and don't have much time to market it.
Since that info might be regarded as an attempt of free advertising again, it will be deleted after few hours, after everybody concerned have read it.
Tube_Dude said:
If I have managed to have a product like that, it's only because I'm spending countless hours on this forum. So far, I didn't sell a single unit yet and I just thought that it might be nice to show my first real world product to fellow members. Actually, I went so far as to show the inside of the product as well which is rather an act of a good will on my part, since because of simplicity of a design, anybody can copy it. I also never protected the secret of parts I'm using as some other makers do.
So it was actually a bit of disappointment to see it was greeted with a hostile response from some members under a false premise that I try to advertise it here. I don't think of selling it here on a forum, because most of you can build it yourself and for rest it's still unobtainium, since the price tag is more than $1000. My Zen amp didn't sell at $500, so I don't have any delusions to sell Gainclone at $1500.
The product will be marketed through regular channels and I don't care much who's buying it. I'm also too busy building it and don't have much time to market it.
Since that info might be regarded as an attempt of free advertising again, it will be deleted after few hours, after everybody concerned have read it.
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