• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

6V6 line preamp

dmm at DCmV with probes touching = zero ..
removed the teflon cap, no difference ... still variable indication at the DCmV position ..

guess I have to recheck the rca's/pot grounding scheme ... which is pretty much as the one at post #1064
 
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Some DC settling during first minutes reflecting to the output caps when not connected to lower load as a main amp probably. Mine does the same. No worries I guess. Watch it over a 50 to 100K pseudo output load simulating an amp over 15 mins.
 
I am not easily worried there is much chance its about something peculiar, its a non loop feedback very simple circuit to do particular funnies. With electronics and various layouts you never know on the other hand, but no, slim chance.
 
false alarm, the output was after the resistor ...

so, I took off the pot and done the wiring again ... and ... bingo !!! 😀


it's dead quite and it sounds wonderful ...
 

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setup is netbook/foobar/m2tech/buffaloII/6v6 ....
with my 2.5 way 92db speakers (horns moved to another room for the holidays) ...

I listened it with zenV4 and f5, with both it sounded excellent, esp with zen cause zen needs the extra dbs (I was listening to it with dcb1) ...

Nick ... thank you for your design and for the unique power supply and all the members who contributed to it ....

now its time to play with some rectifier tubes and output caps ...
 
I listen to flac's from a netbook (mostly 192/24), using foobar and hiface m2tech, then is the bufalloII dac ...
I havent listen through my cd player yet, and I dont have a turntable (tho I have about 500 vinyl records ....)
main speakers are 2w , with deltalite 2510ii in mltl and bc de250 in tractrix horns / x-over based on zilch's econowave work , for the holidays I have taken them to another room and I am using my artemis


yes I use a 50k pot, placed in the middle is allready too loud ....
 
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With such low gain main amps yes, gain aids their dynamics even on sensitive speakers. There was a very easy to understand article by member Pano about gain distribution in the whole chain. A rather underestimated thing in home audio but every one involved in live and recording systems knows its of cornerstone importance.
 
yes, I have read that article, not long ago ...

btw pot is a cheap one, have tried it in dcb1 and it was fine for the job to start wth, later I replaced it with a khozmo one which was much much better of course ...
I probably put a khozmo in this line stage too - with z-foils this time .... 🙂
 
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