Thank you Steve, I hoped to save the extra and redundant cost by asking someone here on this website. It isn't that important, but the 3rd edition would be interesting in terms of what was not yet available to the public.
john curl said:
You're welcome, John. Too bad Pete Millett's only interested in tubes or else he'd probably have them all on his website. Though ultimately there's no reason why we couldn't do something similar for solid state.
If you'd care to send me your 5th edition, I'd be happy to scan it into a pdf that could be made available here.
Saw a 3rd edition in good condition online for about $12. Could do that one too.
What other such "manuals" would you recommend?
se
It is for historical value that I find these manuals extra interesting. For example, there were npn germanium transistors, as well as the more popular pnp transistors at least as early as 1960. I was only interested if they were available in 1958 or so. I will just keep my 5th edition on my reference shelf.
john curl said:
Certainly.
Yes. I think the first germaniums were NPNs and the PNPs followed shortly thereafter.
Ah. Well if I buy the one online, I'll let you know if someone else doesn't offer it up.
Okie doke.
se
More fossiled talk, guess i mistakenly winded up in the SuckTorch thread again.
Can some kind stranger give me directions to Mr Wurcer's superlow noise, huge overload and 0-servo Phono stage thread, please ?
Can some kind stranger give me directions to Mr Wurcer's superlow noise, huge overload and 0-servo Phono stage thread, please ?
I would prefer to present new, elegant, yet still practical ideas in circuit design. Transformers are OK in a pinch, but they are expensive and take a lot of space, chokes are rarely made anymore, cost big money, and tend to pick up hum. Tubes are OK. Obsolete transistors from 25 years ago, such as Vfets, SIT's, early Siliconix mos fets, Supertex complementary mosfets of the past, and Toshiba 2SK146's, J73's (that are worth their weight in gold at this time) are impractical to implement for most who read this thread, even if they are serious about trying something.
Of course, I do not 'own' this thread, and although it started as a 'critique' of my best design to date, the Blowtorch, I had hoped to 'guide' it in meaningful discussion of high fidelity circuit design, between designers throughout the world. However, the moderators apparently think my aspirations, too high handed. I will leave it at that.
Of course, I do not 'own' this thread, and although it started as a 'critique' of my best design to date, the Blowtorch, I had hoped to 'guide' it in meaningful discussion of high fidelity circuit design, between designers throughout the world. However, the moderators apparently think my aspirations, too high handed. I will leave it at that.
I think you did. But you probably may not have to high expectations from public forum, especially not continuously. Anyway, many thanks for great hints in circuit topology.
I would prefer more input from you, PMA. Your emulations are very, very, good. The best that I have seen so far.
There's a SS phono thread here- maybe some in this thread that are interested in the subject will want to participate..
http://www.diyaudio.com/forums/showthread.php?s=&threadid=122129&perpage=25&pagenumber=1
http://www.diyaudio.com/forums/showthread.php?s=&threadid=122129&perpage=25&pagenumber=1
john curl said:
Mmmm. Well, using a transformer for differential input and VAS seems rather novel. At least for home audio. Don't see how you could do something much more "new" except to make it more complicated just for the sake of being more complicated and "new" which rather detracts from the elegance you're also looking for.
As for practicality, I don't see it being terribly impractical.
Well, they do cost more and take up more space than a transistor. But they're not prohibitively expensive unless one makes their living diving in dumpsters and standing on street corners holding up cardboard signs.
As for space, 1-1/2" by 1-1/4" isn't so large unless you're looking to build your preamp inside an Altoids mint tin or something.
150 x 4 output transformers are readily available and work quite well as a center-tapped choke. Big money? What exactly is your idea of "big money"? Anything more than a 20 cent transistor?
As for hum, I haven't experienced any hum problems with this arrangement. But if someone thinks it's an issue, they can replace the choke with a pair of current sources.
So what would you care to offer that's new, elegant and practical?
se
I recall a thread wherein another member posted a numeric count of the number of times Steve had mentioned transformers as evidence of his obsession with transformers. Steve's retort was to post the number of times that the other poster had mentioned transformers, and the number was (as I recall) larger than the number of times that Steve had mentioned them.
The thing that was left out of the whole argument was whether the other poster had been speaking of power transformers vs. interstage transformers. With Steve, it's a given that if he uses the word transformer, it's in the context of a signal transformer. It's his religion.
Steve,
The idea of using a transformer as a driver is problematic. You can either have voltage or current, but not both at the same time. If your output stage requires current to drive it (and they all do), then a simple step-up transformer, although attractive on a voltage swing basis, is not a contender unless you're willing to put a lot of current on the other side.
Of course, you're also left to deal with the DC offset problem because the output of the circuit in question was deprived of its DC connection.
Grey
The thing that was left out of the whole argument was whether the other poster had been speaking of power transformers vs. interstage transformers. With Steve, it's a given that if he uses the word transformer, it's in the context of a signal transformer. It's his religion.
Steve,
The idea of using a transformer as a driver is problematic. You can either have voltage or current, but not both at the same time. If your output stage requires current to drive it (and they all do), then a simple step-up transformer, although attractive on a voltage swing basis, is not a contender unless you're willing to put a lot of current on the other side.
Of course, you're also left to deal with the DC offset problem because the output of the circuit in question was deprived of its DC connection.
Grey
I used transformers 40 years ago in Ampex pro audio. Then, with the Grateful dead, we used transformers for mike splitters, input gain, and for telephone transmission of live musical broadcasts. We used the best transformers available at the time, UTC. Dave Wilson, and all other pro recording companies that I have designed for, have quality interstage transformers available, if needed for RFI reduction or to break a feedback loop. We also had highest quality isolation power transformers available for the same reason. It has been the general experience, that EVEN the best Jensen transformers change the sound slightly and it is preferred to not use them, unless necessary.
In this new age of high RFI in the home. Transformers offer a way of fixing a problem, but only with the added compromise of the input coupling transformers adding a change to the overall sound. Of course, in one of SY's double blind tests, you would probably hear no difference, but I prefer to direct couple high speed circuits and passively shield with aluminum or copper, as best I can. Low level RFI, properly controlled does not appear to do much to a low feedback discrete design.
In this new age of high RFI in the home. Transformers offer a way of fixing a problem, but only with the added compromise of the input coupling transformers adding a change to the overall sound. Of course, in one of SY's double blind tests, you would probably hear no difference, but I prefer to direct couple high speed circuits and passively shield with aluminum or copper, as best I can. Low level RFI, properly controlled does not appear to do much to a low feedback discrete design.
GRollins said:
That's not my recollection. I seem to recall that most of his mentions had to do with interstage and output transformers vis a vis tube circuits. But if you can find that post, that will clear the matter up.
Religion? No. I simply like them. So what? If you don't like them, fine. No skin off my nose. Why do you seem to have to disparage me for my preferences?
I don't seem to recall recommending using a transformer as a driver.
No!
Really?
Thank you for finally setting me straight on that. And to think all these years I believed that transformers were exempt from the law of conservation.
Oh well. Back to the old drawing board.
I didn't offer up just a simple step-up transformer.
Deprived of its DC connection? How exactly is it deprived of its DC connection?
se
john curl said:
It's never been any secret that some prefer not to use transformers. However others do. Is this thread restricted only to those who prefer not to use them?
So, again, what would you care to offer that's new, elegant and practical?
se
I would hope so. It is too disrupting, but then only the moderators can do anything about it.
It has become almost impossible to split posts out of this thread.
From a technical point of view it is too large and the amount of different subjects would require us an all night reading and weeding.
Creating new threads on separate (sidetracked) topics would be very welcome and all players are encouraged to do so.
/Hugo
From a technical point of view it is too large and the amount of different subjects would require us an all night reading and weeding.
Creating new threads on separate (sidetracked) topics would be very welcome and all players are encouraged to do so.
/Hugo
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