• 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

I checked and it stays under 5V:razz: Much more likely that tube hitting wood mounting causing nasty vibrations. Didn't have right tube socket(pcb only with no mounting bracket) so glued to wood top. Got new one coming
PIO is first cap in PSU. :razz:
Truthfully, I am going to give it some time to see if caps "run in" any. Listening to Allison Kraus, you can hear it in her voice. Same with Mark Knopfler on Ragpicker's dream. I did have 4.7uF Obbligato PIO bypassed with Wima MKP10 .47uF. Took it out. Problem is, I have changed too many variables. Also, my FR units would be called bright by some. 6v6 was big step in right direction, driving BA3, but tube rectifier is not what I expected. I have no doubt it is me, but need time to figure it out. I'll be sure to ask questions or send personal PM's when necessary:D
 
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Official Court Jester
Joined 2003
Paid Member
too many posts on too many pages

do you have somewhere proper sch or at least block sch of actual preamp ?

I presume you have shunt reg there ;

if yes , it is hardly that you'll hear too much of difference between solid state and tube rect. , especially if you're using choke in PSU

nevertheless , choke input PSU could be best , in case you have enough ooomphs in xformer secondary

btw - that resistor going from rect. cathode to first pio ; desolder it , put wire bridge instead ;
divide resistor in two , halved in value . and put one of them in each anode of rectifier
decrease their value if needed , to have proper voltage on first pio

that way tube rectifier will work more relaxed
 
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too many posts on too many pages

do you have somewhere proper sch or at least block sch of actual preamp ?

I presume you have shunt reg there ;

if yes , it is hardly that you'll hear too much of difference between solid state and tube rect. , especially if you're using choke in PSU

nevertheless , choke input PSU could be best , in case you have enough ooomphs in xformer secondary

btw - that resistor going from rect. cathode to first pio ; desolder it , put wire bridge instead ;
divide resistor in two halved in value and put them in each anode of rectifier
decrease their value if needed , to have proper voltage on first pio

The 6V6 is built as Salas spec'd it with dual SSHV2 and CCS filament voltage. Sounded angelic. Decided to change PSU, to CLC over CRC, and at same time add, 5U4G Winged "c" blackplate. Too many variables, I know, but it has not improved the circuit. As I said, probably sloppy me and my implementation. Do have parallel 330R resistors before first cap, will break up as you said. Will pursue more slowly now. BTW, you have multiple PM's:D:D:D:D
 
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sorry - I was recommending big motor run in PSU , not on output

modern motor runs are polysomthing in blahblah oil

older ones are real PIO

maybe is easiest to find some Russian PIO caps and bypass them with MKC or small teflon

Gotcha. MOtor run in PSU. Obbligato Fil in Oil first cap in PSU. Obbligao Film in oil as output. FT1 and another Russian was recommended by Salas. Haven't gotten to it yet. Will do though.