OK thanks se, I'll pass on that then. 😀
Okie doke.
I'll go ahead and put you in the "not a serious designer" column. 😀
se
There are many ways to get the early info from the JAES. First, you could find a library that has the copies bound on the shelf. The easiest way is to by the CD set from the AES. It is NOT cheap, but it is convenient. The third way is to find someone nearby who has a bunch of old issues and borrow them. I did that, after the firestorm. Yet another good way is to find a designer of interest and link to their website, if they have one.
However, it takes effort or money, sorry about that. Perhaps you could all pitch in and buy a set for this website, letting Jan keep it, for example. Whatever.
However, it takes effort or money, sorry about that. Perhaps you could all pitch in and buy a set for this website, letting Jan keep it, for example. Whatever.
Perhaps you could all pitch in and buy a set for this website, letting Jan keep it, for example. Whatever.
I don't think the AES would take very kindly to that. It would be a copyright violation.
se
One of the unfortunate things that has become even more difficult, is the dissemination of intellectual information. On one hand, if someone wants a 'Wiki' view of something, it is easily available. However, for a deeper or a historical view, it can be expensive, unless one has access to an extensive technical library. For most here, I would presume that it would not make that much difference, as most here do not design audio equipment professionally, in any case.
I just have recognized that the JC-3 is revieved in the latest issue of Stereophile. It is hard to get here in Germany so i have not read it so far. When i look inside the box it seems to be a bargain.
The Parasound JC-3 is an IC based phono preamp, partially described here as a 2 stage phono preamp. I am still shopping for the best IC's out there.
I just have recognized that the JC-3 is revieved in the latest issue of Stereophile. It is hard to get here in Germany so i have not read it so far. When i look inside the box it seems to be a bargain.
You mean the article "Four More Phone Preamps" in March issue?
Now what are the lamination thicknesses of the audio input transformers talked about here? Sowter, Jensen, Lundhal, etc. Anybody know? If not, why not?
What I use has lamination thickness of about 20 microns, which is under 1 mil.
unless one has access to an extensive technical library.
As e.g. a friend who works at the National library, with extended employee privileges, and used to live across the street.
And access to the electronics faculty library (before they cleared the old lot, afaig from Loek the other day)
Plus unlimited FOB access to a pro Xerox machine.
Nowadays, $74 for a 2-disc set sounds comfy chair cheap and easy.
(anyone in the mood for a couple of thousand lbs of Xerox paper ?)
11 JC-3's for 1 Ypsilon VPS100, and to state that Greece has economic issues.

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Jacco, think of the prestige that the Ypsilon brings Greece. I am serious. It would NOT be competitive to make a cost/effective design in Greece itself. It would have to be made somewhere else, with parts made even somewhere else, and just designed and advertised as a Greek product.
The JC-3 was compared to MUCH more expensive phono preamps, kind of comparing a Honda to a Porsche or a Bentley. It survived the comparison, BECAUSE it was designed and engineered the best that I could do, given the conditions imposed on me from the inception of the design. Many subtle changes were made that would be laughed at here, but my 'sighted' listening tests told me enough to get some changes made. Had I not insisted on these changes, the design would have fared far worse. That makes me sort of a 'wizard' in my boss's eyes, and that helps us both keep gainfully employed, as we can make a series of successful products together, even in this difficult economy.
The REAL challenge will be the next 2 commercially available phono stages that will be introduced by Constellation Audio. Look out Nelson, this future comparison, and Epsilon too! '-)
The JC-3 was compared to MUCH more expensive phono preamps, kind of comparing a Honda to a Porsche or a Bentley. It survived the comparison, BECAUSE it was designed and engineered the best that I could do, given the conditions imposed on me from the inception of the design. Many subtle changes were made that would be laughed at here, but my 'sighted' listening tests told me enough to get some changes made. Had I not insisted on these changes, the design would have fared far worse. That makes me sort of a 'wizard' in my boss's eyes, and that helps us both keep gainfully employed, as we can make a series of successful products together, even in this difficult economy.
The REAL challenge will be the next 2 commercially available phono stages that will be introduced by Constellation Audio. Look out Nelson, this future comparison, and Epsilon too! '-)
OK SY,
So you never did get back to me on if the wet playing induced noise in a record decreases from the start groove to the inner. Your theory that it is a property of velocity should have the noise decrease by more than 10 db. Should be obvious even with out test gear.
Because I haven't tested it yet. 😀 I've been building a new phono stage to accommodate my new cartridge, so the LP system is not in use at the moment. Of course, your experiment assumes that the damage isn't velocity dependent, so a null result isn't dispositive.
John, I'll plug Pieter (remember, I mentioned him a few pages back as someone you'd want to talk to). He owns Tribute, whose transformers I've never tried but have an excellent reputation.
Pieter T, what transformers do you make? You sound like a 'serious' designer to me.
About everything audio related, from tiny SP/DIF to big tube OPT's.
And inductive volume controls.
There are many ways to get the early info from the JAES. First, you could find a library that has the copies bound on the shelf. The easiest way is to by the CD set from the AES. It is NOT cheap, but it is convenient. The third way is to find someone nearby who has a bunch of old issues and borrow them. I did that, after the firestorm. Yet another good way is to find a designer of interest and link to their website, if they have one.
However, it takes effort or money, sorry about that. Perhaps you could all pitch in and buy a set for this website, letting Jan keep it, for example. Whatever.
Well you can get Leach's article on "Noise Analysis of Transformer-Coupled Preamplifiers" here:
http://users.ece.gatech.edu/~mleach/papers/Transformer.pdf
Don't know if there were any follow-ups on any corrections or typos.
Pieter, you have to give more info to make sense of what you truly make. I went to your website and I got some pretty pictures, little more.
However, you do use different transformer laminations for different audio transformers. Why don't you JUST use 12 mil lams? Can't you explain to people here what happens if you do? Thanks in advance.
However, you do use different transformer laminations for different audio transformers. Why don't you JUST use 12 mil lams? Can't you explain to people here what happens if you do? Thanks in advance.
Unfortunately, Pooge, it doesn't say much about the transformers, themselves, just how they can help to improve S/N in limited quality input stages.
An awful article. A prime example of why I not only don't subscribe to this magazine, I rarely read it even for free and never take anything it says seriously.
ftp://194.45.31.243//Parasound/Revi... Four Phone Preamps incl JC3 - March 2011.pdf
ftp://194.45.31.243//Parasound/Revi... Four Phone Preamps incl JC3 - March 2011.pdf
However, do you SELL your transformers?
No John, being a socialist I actually give them away for a small additional fee 😡
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