I had to take a vacation from tube amplifier fiddling after my life got too busy. Im back at it. I drew this up some time ago, but i just now got to wire it up in a prototype form. Best sounding circuit I've yet to listen to. Compared to a triode driver/preamp this tube is far more precise/articulate without losing the part that makes tube amplifiers awesome
An externally hosted image should be here but it was not working when we last tested it.
Following up my sharing with a question. Anybody put together a 6au6 line level amplifier or have an idea of how to go about designing one? I want to build a tube buffer for my subwoofer channel that is partially for balancing the volume with the main amp. is it as simple of copying my circuit as seen above and using a voltage divider on the other end to attenuate it down to line level voltage?
i was actually considering bypassing it, i dont have parts on hand to do that tho, need to order some. using up my stock of 10 uF caps on building the gain stage
maybe that feedback is desirable tho. ill have to carefully compare them. my quick and dirty test used a 10k resistor in there(as thats what is installed at this moment)
and yea, i guess your right on it being a beam tetrode.
i was actually told in the past that as my 300v supply is regulated that the bypass on the 807 screen wasnt needed. i was going to compare but you agreeing with my original thoughts changes my mind back on that decision
going to rip apart my amp and rebuild it as described in the schematic this coming week, ill report my findings with experimentation and actual b+ voltage
maybe that feedback is desirable tho. ill have to carefully compare them. my quick and dirty test used a 10k resistor in there(as thats what is installed at this moment)
and yea, i guess your right on it being a beam tetrode.
i was actually told in the past that as my 300v supply is regulated that the bypass on the 807 screen wasnt needed. i was going to compare but you agreeing with my original thoughts changes my mind back on that decision
going to rip apart my amp and rebuild it as described in the schematic this coming week, ill report my findings with experimentation and actual b+ voltage
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so in other words you like the idea of ~2.5k resistor there with an 10uf or so bypass like i assembled the 6au6
resistor i guess in theory helps prevent oscillations
I should try it out as each... who knows, like you said you get varying results and i might in fact enjoy one of them.
anything else i should experiment with? perhaps bypassing the cathode resistor on the driver?
resistor i guess in theory helps prevent oscillations
I should try it out as each... who knows, like you said you get varying results and i might in fact enjoy one of them.
anything else i should experiment with? perhaps bypassing the cathode resistor on the driver?
Im all up for trying out different combinations/experiments to find out what i like best. 100-200 ohms will be on my list of things to experiment with.
I did the prototype experiment mostly because i wasnt sure if i liked pentode or triode sound better yet, so i decided to build a circuit that mostly went all out on the pentode, and i was ecstatic with the results. Guess im taking more of the experimentalist approach
I did the prototype experiment mostly because i wasnt sure if i liked pentode or triode sound better yet, so i decided to build a circuit that mostly went all out on the pentode, and i was ecstatic with the results. Guess im taking more of the experimentalist approach
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