Hi Staffan, comes out nicely on the box. Did you get any difference in tone with the DC in the filaments nonetheless?
DC worked fine and I didnt hear much of a difference so far. Gonna work off B+ ripple tomorrow and then compare to elevated AC.
But overall its a lovely little rat-amp. I will try it on a friends 6C33 OTL some day, which is especially hard driven.
Staffan
But overall its a lovely little rat-amp. I will try it on a friends 6C33 OTL some day, which is especially hard driven.
Staffan
Hi all,
I've just built 6V6 pre for my friend. Here are some pics. Sound is very good on mid, bass and rich tone.
My schema is based on Salas' one, but I use AC filament with hang of 40Vdc. PSU is with 5V4 tube, CLCRCLC for separate chanel. No hum AC, but I have some hizz on one chanel. I think it's tube noise.
I've just built 6V6 pre for my friend. Here are some pics. Sound is very good on mid, bass and rich tone.
My schema is based on Salas' one, but I use AC filament with hang of 40Vdc. PSU is with 5V4 tube, CLCRCLC for separate chanel. No hum AC, but I have some hizz on one chanel. I think it's tube noise.
Attachments
Good looks. Did you take any anti microphonic measures? Its the common cathode 15dB gain circuit yes?
No.... unfortunately I do not build anything with bulbs for long now... but I will.
I am using a p2p dcb1 with V12r shunts as a reference.
I am using a p2p dcb1 with V12r shunts as a reference.
DCb1 is no slouch by any measure. It is my SS volume control. If you dont need the gain, try the CF. It will be next for me. I will have both versions interchangable, depedning on my mood.
cathode follower. It is on first page. Would be good alternative to DCB1 if no gain is needed. Check first page.
Thank you.
I know it is a good contender... that is why I am following.... It will happen soon 🙂
I know it is a good contender... that is why I am following.... It will happen soon 🙂
Nice Salas. I had kids here today so it was more Minecrafting then soldering but I made those:
The hawkeyed can see that it has the same screwhole placement as SSHV2, so I can interchange them. The cap-thingy will become an R-C then.
I also did some quick voltage measurement and I ended up between 245 and 310 V B+ with 2,2-6,6 k as last R. That puts the bias to between 16,6 to 21 V which might put me in a strange little corner on the curves. Maybe a 680 DCR LL1660 would be more suitable.
Then I'm stuck with a strange groundnoice. I rewired stargrounding without results. DC-filaments and more smoothing C dont affect it.
Well, one's got to save some for the day after...
Staffan
The hawkeyed can see that it has the same screwhole placement as SSHV2, so I can interchange them. The cap-thingy will become an R-C then.
I also did some quick voltage measurement and I ended up between 245 and 310 V B+ with 2,2-6,6 k as last R. That puts the bias to between 16,6 to 21 V which might put me in a strange little corner on the curves. Maybe a 680 DCR LL1660 would be more suitable.
Then I'm stuck with a strange groundnoice. I rewired stargrounding without results. DC-filaments and more smoothing C dont affect it.
Well, one's got to save some for the day after...
Staffan
Thats possible. Usually that takes us to motorboating but i can easily swap the filterchoke to a resistor and see if it there. I could also rig the scope. Its downhill skiing on the agenda tomorrow so lets see what it brings.
I changed last RC and also second C a couple of times so it shouldnt be there . And its overkill 1 k carbons on the grids. But you never know with chokes and capacitors.
Well yes. I could check with a lil resistor network instead of beasts.
Cathode Circuit is currently just the chokes (930 DCR 100+ H), 10 uF output caps decoupled with 10 k to ground.