• 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

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Stajo is sailing in his warm bunk, watching an 8-year old soon to wake up and in a while go to school:)

Cool video, no I havent yet tried the USSR. Cathode rays are cool.

Actually I plugged the barge in a little quickie yesterday. Without AC filaments referenced to anything. That makes a wonderful sound:D

Then I tried to silence them with referencing them first to ground then to to different potentials with a pot divider from B+

I made it so I can go from +5 to +95 volts over gnd, but it made small differences over ground ref wich still make a little hum. I guess that signal taken from a cathode that is only an oxide layer from a 50 Hx filament is hard to accomplish. I will go to DC (District of Columbia) today.

I also remade the schema a bit, will post later.

Full to the gunwales or I'll walk the plank
 
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Yes, it was an early shot but today is "work-from-home" day so maybe I'll come with some updates whilst you get your beauty sleep;)

Me sleeping beauty, when you pricked your finger on the 6V6 spindle the other day...Watch it, good fairy gives 100yrs sleep for such if she happens to be around.:D Tchaikovsky - Sleeping Beauty Waltz - YouTube
 
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Heres the current config for sleeping beauties while I'm deep diving for some DC stuff
 

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Yea okok. I know you guys enjoy some pix while Im putting on the second pot of coffee. The barge is playing now, all uneathed and unisolated so its still picking up some hum/noice. And its extremely microphonic. It could be a challange to get that away. Plonging a tube with finger almost makes a loop.

I first run it on a Hafler EL84 and subjectively I like that better with its own volume pot and no pre. But now in a 6L6 Candela and its rocking. Firm (ish) bass (feel it in the walls:D) and decent mid/top. Well its still early.

Brb after coffee.
 

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Since its so darn sensitive I might have to give it an overlook on EMI-shielding, earthground the metal and try to isolate physical trafo-hum etc to give measures a fair chance. I might put in a 20k plastic Alps also but thats gonna take some time. Poll?
 

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