John Curl's Blowtorch preamplifier part II

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Unfortunately, B+D does *not* test their semis. They buy and resell. I am sorry to report that the Toshiba J74s that I acquired from them last year were in fact the same bogus parts as one can get on ebay. :(

Caveat emptor.

_-_-

Mr. Curl, I heard you were at AES NYC, I was there on Sat but did not happen across you, there. Wish I had known you were in town.
 
Unfortunately, B+D does *not* test their semis. They buy and resell. I am sorry to report that the Toshiba J74s that I acquired from them last year were in fact the same bogus parts as one can get on ebay. :(

Caveat emptor.

_-_-

Mr. Curl, I heard you were at AES NYC, I was there on Sat but did not happen across you, there. Wish I had known you were in town.

Bear could you send me a suspect part, I might be able to strip it. BTW I've had no problem with ebay parts, you simply can not fake the Idss and low Vp or noise.
 
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There's NO MONEY IN DISCRETES JOHN. Period.
Scott has said the same thing numerous times. Take those penny parts from Toshiba/NEC and put them in a very expensive pre-amp such as a Blow Torch II, Toshiba/NEC do not see any of this $. Maybe JC does not see much/any of the profits either? Makes you wonder how Linear Systems can justify developing new jfets when the rest gave up.
 
Linear Systems apparently makes its biggest effort in supplying 'obsolete' parts to the military/industrial complex. Many discontinued parts are produced by them. So, they have found an added niche in making complementary jfets, that Toshiba, Hitachi, and many others have abandoned.
Now, what about the 'future' of discrete devices? Of course, it is limited, just like tubes are limited. However, it can be shown that the BEST audio is made with discrete semiconductors or tubes still, and this will motivate the IC people to catch up (sonically). Of course, many IC designers think that IC's are all we need, but I beg to differ, AND we have stockpiled enough discrete parts, along with the added input from Linear Systems, and other semiconductor companies to make SOTA products for many years to come. No, they will not be in the cheap stuff, but the really excellent audio designs still possible from both tubes and discrete semiconductors will 'force' the quality of the large scale IC manufacturers to do better, just because there still is a difference sonically, and in future, we will have truly excellent, all IC based products.
 
Scott, you will shortly have a PM...

Or you can mail me some Red Fuming Nitric Acid (ha ha)

_-_-

PS, you must be the only one to have no fakes from ebay then! You can fake the Idss, the Gm and VP don't match up, and as far as noise, I don't have a way to test noise. :(

OK I'll post both pics when I can. I meant the Idss at low Vp can't be faked easily or it would be an equivalent device. The Fairchild J177 series I have (the ones with that have high Idss) use a very different dull encapsulant from the Toshibas.
 
So, they have found an added niche in making complementary jfets, that Toshiba, Hitachi, and many others have abandoned.
Even so, still hard to figure on a return of investment for them considering a very very small market.
I would expect Scott and others to challenge your statement as to the inferiority of modern day IC's in audio, so the debate continues :D
The way I see it, almost all the audio data are primarily from a digital source, so if it is flawed, because of IC's, then no discrete ckt there after makes any difference, as it can not correct the source.
Oop's did I stir the pot, not my intention
Cheers
Rick
 
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Even so, still hard to figure on a return of investment for them considering a very very small market.
I would expect Scott and others to challenge your statement as to the inferiority of modern day IC's in audio, so the debate continues :D
Oop's did I stir the pot, not my intention
Cheers
Rick

No, IMNSHO FET's and IC's have make phono stages that are indistinguishable from each other for a long time now. Just that there is too much to lose by proving it one way or the other. Be it sanity, patience, friends, money, whatever.
 
Well, it has just not been MY experience that I can make phono stages of IC's as good or better than phono stages of discrete fets.
I do both, I am successful at both, I use the SAME RIAA parts on both. YET, there is a difference, and I have heard it with my own ears, in my own apartment.
When I was developing the Parasound JC-3 phono stage, I compared it with the built-in Vendetta in my CTC Blowtorch, by putting the JC-3 in a line input of the same CTC Preamp.
I used the SAME input loading. RIAA was within .l dB. Still a difference, not much of a difference, but still a difference.
That is my experience, and I challenge Scott to make an IC based phono stage that is equal or better than the Parasound JC-3. However, he has to give a real challenge, not an engineering guess.
 
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