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Old 15th September 2012, 02:15 AM   #1871
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Quote:
Originally Posted by lhquam View Post
Buzz: You might consider this modification to the circuit. Add 20 ohm pots in parallel to the source resistors. The pot wiper is tied to the capacitors. This provides complete freedom to experiment with balance of top and bottom JFET modulation, and the pot adjustments do not affect the DC bias. Also, the source resistors retain their normal values and WATTAGE.
This is such a cool idea !!!! Zowieee ....
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Old 15th September 2012, 02:17 AM   #1872
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Has he had a chance to hear any of your other amps?
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Old 15th September 2012, 02:20 AM   #1873
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Originally Posted by kasey197 View Post
This is such a cool idea !!!! Zowieee ....
Just make sure the pot is correctly rated for the job
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Old 15th September 2012, 02:33 AM   #1874
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Not a problem. The pot is 20R or more in parallel with the normal source resistor. Look at post #1844 F6 Amplifier
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Just make sure the pot is correctly rated for the job
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Last edited by lhquam; 15th September 2012 at 02:36 AM.
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Old 15th September 2012, 02:33 AM   #1875
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Originally Posted by Nelson Pass View Post
Maybe he just likes the sound of transformers.

Possible isnt it. If being totally honest, I have to admit there is a certain magic to a nice triode tube, but I am not willing to concede that tubes have the market cornered. This amp, more than any other, has shown me the potential to influence the sound of an amp. It is not with parts but design, something i believe you have tried to show. The RO85 will make its way into this design. HAve you found different sounds in similar topologies between the two SS parts. On paper, they see, to have different responses. I lost interest somewhat in R085 after reading SiT Nemesis article. Shouldnt have given up so easily.

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Originally Posted by Melon Head View Post
Has he had a chance to hear any of your other amps?
He has heard them all. The other amp he likes is BA3 with Ba2 output stage, as do I. I need to figure out if this sound i like is the result of harmonic breakdown, transformer, or even SS fets. Laterals are another transistor that I really like and i enjoyed them in this amp. I am going to post some stupid ideas tomorrow in my new thread. I am really going to play with this thing, as it is so easy to do.
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Old 15th September 2012, 02:46 AM   #1876
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Quote:
Maybe he just likes the sound of transformers.
Friend Rene Jaeger has been working on a hybrid topology, with SS PP circuitry using high voltage devices that run at tube voltages. Startlingly sweet sound and with interstage and input transformers to complement the PP OPT, one that was intended for a PP 300 B amp (Lynn Olson's Karna amps had the first pair).

Seems to work well with SS Guitar amps also, a high performance 70 volt line matching transformer works amazingly well, with no other changes.

Bud
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Old 15th September 2012, 02:51 AM   #1877
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Bud,
I want to try choke loading my 6v6 pre, got anything that will work. Need 5K and 20mA minimum, with more current capability being better, I assume. Once again. Don't really know. Some nutjob that goes by Choky hinted at it. He gives good hints in the past.
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Old 15th September 2012, 04:31 AM   #1878
lhquam is offline lhquam  United States
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I have been tweaking the pots. With Rs=0R20 I found this very interesting pot combo. The pot wipers were quit low, perhaps 0.1 of the hi FET and 0.3 on the low FET. I do not have an accurate way to measure either the pots or the source resistors to say what the exact resistor values might be.
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Last edited by lhquam; 15th September 2012 at 04:35 AM.
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Old 15th September 2012, 04:44 AM   #1879
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Buzz, I admit choky might seem a little on the Crazy side but, he obviously knows this sheeet
And,
So, try to get by the Serbian language barrer and don't sell him short
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Last edited by flg; 15th September 2012 at 04:48 AM.
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Old 15th September 2012, 05:02 AM   #1880
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lhquam I have a for real wheatstone resistance bridge if you want to send them to me.

Bud
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