The Amp Garage

Something I just realized today, the treble pot acts very oddly in this amp because of the loading of the trem pot. You get the same sort of signal dump as you do in a typical bf/sf fender circuit, but because it is right at the treble pot, it acts more like a "thin knob", as you turn it up. The amp...

Cool thanks for that. I wonder how those numbers change for five 50W resistors. Certainly it wouldn't be a 60"x60" box
I've got a chassis kickin around here that's 16"x 7" and .09" thick. I imagine that will be plenty, based on the sizes of boxes I've seen used.

Lookin to build the 2/4/8 version 2 : https://www.aikenamps.com/images/Docume ... myLoad.pdf

What sized Hammond enclosure will I need for proper dissipation and would I need any sinks?

Without turning on standby? Check the rectifier

Funny you should ask, I was just about to pull mine into rotation and do some playing. Mine sounds killer, though it is tube rectified
I think we still had a few other unanswered questions didn't we? A pot value and probably voltage divider or something between stages iirc

I was gifted a SF Twin chassis. Who's making boards these days for Dumble stuff I could drop in?

This is exactly what happened , I believe. One more thing to look out for y'all.
This was a total fluke , and a nasty shock that went in one arm and out the other. I'm fine , and have been shocked a handful of times, but I'm going to the doctor tomorrow to make sure

Troubleshooting a BF Showman that apparently cut out on a gig. Turning it off/on returned full volume. I was troubleshooting the speaker cable that was being used, and had it plugged into the speaker jack of the amp on one end, and the other into my female to male speaker cable extension, then that ...

Qustion here, is the 18K plate stage considered a Cathode Follower(looking at original schematic)? Is that why it can be DC coupled, in the original schematic? However there is signal coming off the plate too, no? through the small 820pf coupling cap? or is that a function of the varistors? So based...

That's awesome! Yep I'm sure I put a 1M stopper at the concertina, I remember tying different values at some point, and there was no high end loss even at 1M. Thanks for confirming the dc coupled PI. Yea the amp works so well with single coils because of the unbypassed, perhaps dark flavored, cathod...

Smokebreak, Did you stick to the original schematic? Have you measured voltages? I am especially interested in the cathodyne; how balanced or unbalanced it is. For the most part yes, but that was 10 years ago! Certainly I kept the PI and power section the same, as well as the vibrato section....als...

Yea that tone control is neat, it acts as a mixture of cathode bypass on one side, and high frequency dump on the other, or a mix. I think the overall sound of the amp is unique due to the combo of high Rp/Rk values on the unbypassed 1st stage. I put an added stage in front , on my amp, using a seco...

Revisiting this amp I built 10 years ago (!). It has become my shop amp over the past few years with a great sounding Jensen blackbird alnico speaker. I ended up modifying over the years, and built an extra gain staged in front of the posted schematic. It's a thick, kinda dark amp, and sounds great ...

Should be good enough for rock n roll! Someone else may want to confirm, I don't have the DRRI in my possesion anymore

My apologies, I had 4 incorrect measurements. I think everything adds up now...

The length is actually 16 1/4
The height is actually 2 7/16
2 other intraboard measurements were off by 1/8