Tube Amp Archive

thank you fabio,I think its worth trying,before trying dc filaments,my express clone sounds great but hums!

heisthl wrote:Go up this page 5 posts to the schematic in my post.

thank you so much..what if you have 300v secondary?which resistor value do you suggest?if you had the time to show me the calculation method,would be reaallly appreciated!must be something that involves ohm law...

[quote="markr14850"]For me, a 10-turn 200ohm precision wirewound pot for balance, with about ~20v of elevation on the wiper does the trick. It's a *huge* difference. For people who have never tried this before, add this to an amp tonight! Even with the 10 turn pot, I'm amazed at how small a window o...

I posted an mp3,buzz is louder in real life,than what hear at the beginning and the end of the demo,in the middle me playing.Volume around 2(I'm home!!),vinetto strat straight in the express,shure 57 straight in the middle of a 1x12 celestion gold 100w,in a small anniversary serie marhall cab. To an...

its something more than annoying,but not so bad you couldnt do a gig,if you compare noise and volume..and,yes its higher than 60hz to my ear.I'm carefully reading the post you indicated,and I'll try the elevation method,I checked the heater's center tap,its grounded,caps are grounded,I tried with a ...

Hi everybody,big problem here..I recently finished my express build,I have a toneslut output transformer that's buzzing,more than they normally do (IMO). I didnt follow exactly the layout(I'll post some pictures one of these days)cause I used a different chassis,I suspended the heater wiring OVER th...

ok merlin,thanx a lot,this is very clear.I'm trying to put some ideas together,about this "Resistor vs.choke"thing.I found an interesting forum page about this :http://music-electronics-forum.com/showthread.php?t=9402 it seems amp builders use resistor because is cheaper than choke(cause choke turn ...

hi merlin,one question to you,or anyone so kind to answer:why do you think 5 watts its enough?In the meantime I found 15w 1kohm,who knows the proper calculation to find the right dissipation power for this resistor?
also,is 50 volts for the electrolitics in the bias section too low a voltage rating?

Wonderful!!I got all my beautiful parts and caps and cables,I feel a little guilty now!!One question:a power transformer as an output transformer?How does it work,how did you get there?

thank you so much,I'm a i..ot!I wasn't able to find the right resistor on mouser,unless I used "cement"and "xicon"in the search field.Problem with your language.Thanx again

Hi everybody,need help with the big 25w 1 kohm resistor in the supply board.It seems really difficult to get one,I got one from mouser and here's the surprise:there was no image available and when I opened the package I found one reeeally small Caddock resistor,same size of a LM three pins regulator...

thank you so much!!its been a great help,amp garage is a great thing!g

thank you mark...could you help me with my question on the transformer test?

hi everybody,I got an old ampeg gemini II,totally gone,someone modified it many years ago with a transistor power out,but left there the output transformer.My questions:the ampeg gemini II had 2 7868 tubes,is this output transformer usable with other tubes(I'd like to build a trainwreck clone with 2...