start for a SSS ,help
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Re: start for a SSS ,help
ok thanks ToneMerc,  but I think that 60V 100mA for bias, is too much low voltage for cathode driver type!
			
			
									
									
						Re: start for a SSS ,help
If you need a higher bias voltage you can "reverse" hook up a filament transformer to the 6v supply giving you 120 ac out - assuming the filament transformer is spec'd at 120 in to 6.3 out.
			
			
									
									
						- David Root
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Re: start for a SSS ,help
There is also the matter of the internal local negative feedback circuits in the preamp which are a part of probably most SSS circuits, based on my own digging around. 
Also the headroom limiting mechanism I have heard of in some undetermined part of I believe the preamp or possibly the PI circuitry is, if true, likely connected with the local NFB in attaining the characteristic singing/sustaining tone of these amps.
General description, I know, not prescriptive detail, but it can inform some possible imaginative development.
FWIW, if you are going to use a 12AX7 as a driver I think you will need at least -130V or so cathode bias but only about 5mA current. Higher current drivers eg 12AT7, 6CG7, 12BH7 would need more current I think. I bought a small transformer that can provide -175V bias with a FWB rectifier from 120VAC secondary. Hammond 262B12. Also has a 12V6 secondary that can run a 12FQ7 driver's heater, which I might try. Andy Fuchs uses a 6FQ7 driver in his Clean Machine.
			
			
									
									
						Also the headroom limiting mechanism I have heard of in some undetermined part of I believe the preamp or possibly the PI circuitry is, if true, likely connected with the local NFB in attaining the characteristic singing/sustaining tone of these amps.
General description, I know, not prescriptive detail, but it can inform some possible imaginative development.
FWIW, if you are going to use a 12AX7 as a driver I think you will need at least -130V or so cathode bias but only about 5mA current. Higher current drivers eg 12AT7, 6CG7, 12BH7 would need more current I think. I bought a small transformer that can provide -175V bias with a FWB rectifier from 120VAC secondary. Hammond 262B12. Also has a 12V6 secondary that can run a 12FQ7 driver's heater, which I might try. Andy Fuchs uses a 6FQ7 driver in his Clean Machine.
- RJ Guitars
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Re: start for a SSS ,help
Exactly correct -- The SSS is not simply one design and what I learned was a combination of real info, assumptions, and my own best guess about how I might build this amp. One fact that seems pretty solid is that each SSS was a unique creation built for a specific individual. The limited info from folks and photos that have had an inside look at these amps verify some significant differences between the various builds.dreric wrote:These schematics have been floating around TAG for a while now. the first two are Rj's musing into the SSS. In this thread:
https://tubeamparchive.com/viewtopic.php?t=7972
People have made amps (longhorn) but are not open with the info. For now the SSS remains a mystery and seeing that no two are alike it will most likely remain so.
Eric
The constants seem to be: Loud clean power, large heavy amps, and somebody famous on the other end of the guitar cord.
rj
Good, Fast, or Cheap -- Pick two...
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- LeftyStrat
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Re: start for a SSS ,help
Was that a curly cord? And what was the string gauge? LOL.RJ Guitars wrote: The constants seem to be: Loud clean power, large heavy amps, and somebody famous on the other end of the guitar cord.
rj
Honestly, and this might be heresy, just buy a vintage Ampeg SVT head, the tone section is probably superior to the SSS.
And with that head, you'll be able to play Jimmy Page's favorite solo ever:
http://www.youtube.com/watch?v=rBllejn5fVA
http://en.wikipedia.org/wiki/Reelin%27_In_the_Years
It's never too late to have a happy childhood.
						Re: start for a SSS ,help
The band I was in years ago used to cover that song.
We murdered that solo nightly!
			
			
									
									We murdered that solo nightly!
Tom
Don't let that smoke out!
						Don't let that smoke out!