Search found 209 matches

by flood
Thu Dec 18, 2014 3:26 am
Forum: Technical Discussion
Topic: Dummy load/silent recording - Output Transformer ringing?
Replies: 8
Views: 1062

Re: Dummy load/silent recording - Output Transformer ringing?

Reeltarded wrote:Transformer sing is what you are saying. I hear it all the time, even when not loaded and ripping on a 100w amp. If you stand 3' away it will drive you insane.
Yes! This is a 15w about a foot away. The main issue I have is that it sounds really nasty in the DAW
by flood
Thu Dec 18, 2014 3:04 am
Forum: Technical Discussion
Topic: Dummy load/silent recording - Output Transformer ringing?
Replies: 8
Views: 1062

Re: Dummy load/silent recording - Output Transformer ringing?

Thanks a ton for all your answers - to answer some of the questions briefly, the "ringing" of the OT could essentially be thought of as microphonics - i can hear what i'm playing, high frequencies only, of course, through the OT. I could rewire the load for 7.5 ohm operation, which should be closer ...
by flood
Wed Dec 17, 2014 1:35 pm
Forum: Technical Discussion
Topic: Dummy load/silent recording - Output Transformer ringing?
Replies: 8
Views: 1062

Dummy load/silent recording - Output Transformer ringing?

Hey there everybody, I'm building a load box for a friend as way of reparations for dropping his Strat on concrete. I'm using a 4-resistor network in series-parallel to give me a total of 30 ohms at 200W, for the 8 ohm tap. The idea here is not to attenuate, but to build a load box for silent record...
by flood
Thu Jan 24, 2013 9:45 am
Forum: Technical Discussion
Topic: Mosfet VVR question
Replies: 33
Views: 11796

Re: Mosfet VVR question

Do you have a 'gate stopper' resistor at the MOSFET, or is this on the turret board? This needs to be as close as possible to the MOSFET for all the same reasons that grid stoppers need to be right on the valve sockets. Could be your problem. If it is the problem, it will be a problem for a differe...
by flood
Wed Jan 23, 2013 1:52 pm
Forum: Technical Discussion
Topic: Mosfet VVR question
Replies: 33
Views: 11796

Re: Mosfet VVR question

I've been using IRF840Bs in my VVR installations, and none of them have lasted particularly long. It would help to know voltages & current requirements of the circuits that you're building. As long as you don't exceed the voltage rating of the IRF840, and it's adequately heat-sinked, it's hard to s...
by flood
Tue Jan 22, 2013 10:32 am
Forum: Technical Discussion
Topic: Mosfet VVR question
Replies: 33
Views: 11796

Re: Mosfet VVR question

at the risk of reviving a very dead thread: hi again to everybody from india. was on a hiatus from the amp hobby, and thought i should peek back here to solve my VVR problems, thinking i could get away with paralleling my MOSFETs. I've been using IRF840Bs in my VVR installations, and none of them ha...
by flood
Tue Jun 05, 2012 11:14 pm
Forum: Technical Discussion
Topic: ampclones Who are these guys?
Replies: 34
Views: 13963

Re: ampclones Who are these guys?

coolidge, those boards are beauties! thanks for sharing the link to the manufacturer, although i don't see myself making use of it for a long time. funnily enough i was designing hybrid turret/PC boards for my own amp designs, but then i decided to trade amp building for grad school. i'll probably g...
by flood
Wed May 18, 2011 10:08 am
Forum: Trainwreck Discussion
Topic: My X10 has begun
Replies: 190
Views: 36952

Re: My X10 has begun

surfsup wrote:
Bigger means they wont fit n wont look as nice! 8)
oh my god, that's what she said. :D

compliments on very nice looking build, i'm sure she'll sound awesome.
by flood
Sat May 07, 2011 9:51 am
Forum: Trainwreck Discussion
Topic: Sub miniature Blues Express - blatty distortion
Replies: 4
Views: 2213

Re: Sub miniature Blues Express - blatty distortion

thank you ian, think i found the problem - the 7806 regulator must have crapped out at some point, taking heat damage. filament voltage was down to 4V and not 6V as initially measured. going for AC heaters with a 100R/100R virtual CT referenced to the junction of a 220k+100k bleeder series pair (try...
by flood
Sat May 07, 2011 8:49 am
Forum: Trainwreck Discussion
Topic: Tiny blues express combo / 12AU7 PP w. cathodyne PI
Replies: 10
Views: 6670

Re: Tiny blues express combo / 12AU7 PP w. cathodyne PI

servus martin, thought i should post here and ask you for your assistance again - i've finished my build and could use a little help... here's my thread regarding my 12AU7 express problem: http://ampgarage.com/forum/viewtopic.php?t=14650 i did make a couple of mods just a minute ago, switched the ca...
by flood
Wed May 04, 2011 2:02 pm
Forum: Trainwreck Discussion
Topic: Sub miniature Blues Express - blatty distortion
Replies: 4
Views: 2213

Re: Sub miniature Blues Express - blatty distortion

ok, swapping the tubes again didn't help. i'm wondering if i should go back to AC coupling. also thinking of increasing the grid leak resistor, R9, at V2A from 68k to 100k-220k, i have a feeling that 68k resistor is a bit too low. something has gone awry here, not sure why the sound just cut out lik...
by flood
Tue May 03, 2011 4:53 am
Forum: Trainwreck Discussion
Topic: Sub miniature Blues Express - blatty distortion
Replies: 4
Views: 2213

Sub miniature Blues Express - blatty distortion

So I built a Blues Express based amp (with a voxy tone stack though). Schematic is attached. I followed Merlin's instructions with respect to cathodyne PI design, using a 1M grid stopper and 100k grid leak with the diode... and it sounds nasty for some reason. Initially, the cathodyne PI was AC coup...
by flood
Wed Mar 09, 2011 11:14 am
Forum: Garage Talk
Topic: Shocked the ^&^$%#$# out of myself!
Replies: 36
Views: 8066

Re: Shocked the ^&^$%#$# out of myself!

i've made it a point to use a bleeder resistor on EVERY amp i build now. no bleeder, no power up. got shocked (by AC though) a couple of times, didn't enjoy it at all.
by flood
Tue Jan 18, 2011 6:11 am
Forum: Technical Discussion
Topic: 1/4 A slow blow for HT fuse?
Replies: 9
Views: 2609

Re: 1/4 A slow blow for HT fuse?

I've used 200mA SB in the secondary CT-to-ground of my 18W design. I'm pretty sure this is not the right way to do it, but definitely took it off a schematic as i knew very little about building amps back then.

i'm omitting the fuse on the secondary entirely in my soldano atomic 16 build though.
by flood
Fri Jan 07, 2011 7:31 am
Forum: Trainwreck Discussion
Topic: Tiny blues express combo / 12AU7 PP w. cathodyne PI
Replies: 10
Views: 6670

Re: Tiny blues express combo / 12AU7 PP w. cathodyne PI

Ha! I'm doing the same thing - converting my firefly to a 1.5W blues express type amp, using the cathodyne PI and 470R//47u (non-polarised) cathode resistor on the 12AU7 power stage. 8k2 grid stoppers though. other changes: the tone stack is a bit different - using the Vox TS (because i only have 3 ...