The Amp Garage

Jana wrote: Show me a schematic that uses a 12DW7 in a long tailed pair and I will eat my shorts.

heh!

Using a 12dw7 in a long tail pair phase inverter is about the worst possible place to put it. If you want lower gain try an AT7 in the phase inverter. And/or try an AU7 in the first stage. well, yes and no. A direct replacement will sound lousy, but with some modification the 12DW7 can be a screame...

Voodoo_Man wrote: 317VDC with FW Center Tapped Rectification and Capacitor Input (121VAC Supply), No load

oops -- forgot to mention mine are real life numbers, too, but with load. I more or less got the same results as you. Thanks for clarifying.

Hello I think you could make a nice champ/princeton style amp with the output tranny.but you would need alittle more juice in the power tranny.I think the ex269 specs@190 0 190 which gets you about 260 B+. with SS rect.when you would want 300 + IMO.I built a champ style amp a few years back with el...

I bought a Sourmash 1x12 fairly recently. He did a very nice job on the tolex, better than the Weber cab I bought last year The speaker cutout was not as perfectly round as it should have been, but I managed to mount the speaker securely. It's a very lightweight cabinet, but it feels and seems rathe...

Fire in the Store!!

http://www.sacbee.com/latest/story/1471436.html

If I am not mistaken the blackbirds are based on the blackface era deluxe amps. Yes they are. BTW, I ran into Ben a couple of weeks ago and he told me some great news: via Ben's association with Joe Satriani, Steve Vai was blown away by Ben's amps and got him together with Carvin to completely re-d...

Carlin, check here: http://www.angela.com/ and here:
http://www.bltsound.com/index.php/categ ... r-speakers

Thanks, Jana, for your replies. I appreciate the help. I will, in fact, employ the circuit you describe. But (Please don't take offense at this), I was asking how to calculate a fixed-bias circuit. Basically, how/why was a 220k/180k/etc. dropping resistor chosen, as well as the 15k between the filte...

OK, so now that some things have been clarified, I'm still confused as to how to actually calculate and approximate not only the dropping resistor, but the entire circuit. It seems like skyboltone was on the right path. Can anybody maybe give a step-by-step on how to do this? I really need the help....

dave g wrote:That PT is only rated at 100mA. Seems a little light to me...

huh?

273BX 182VA, sec. 350-0-350, DC ma 175, Fil.#1 (rct) 5.0V @ 3a, Fil.#2 (htr) 6.3V @ 5.0a ct.

Thank you; this is great stuff, skyboltone it's very much what I was seeking to find out. I hope others will chime in, too. I know I could use even more clarification.

I'm getting ready to start on the new build utilizing a pair of 6L6's in fixed bias. I'm using a Hammond 273BX PT and it has no bias tap, which means I have to tap off the HV. How do I calculate the size of the dropping resistor to generate the desired negative voltage?

I wish the ticket was Obama/Clinton so we could get a black guy and a babe in the same vote. Ok, now I have to throw the penalty flag. It is not acceptable to use the words "Hillary Clinton" and "Babe" in the same sentence unless you are referring to the animal in that pig movie. Old log legs is th...