Tube Amp Archive

Also, the PI input cap - should that be 0.022 rather than 0.0022?

Would anyone have suggestions of what reverb transformer and pan to use for that SW22R schematic? I've made a few amps before but never put in reverb...

Good one with the Sharpies - I wouldn't have thought of that! Maybe time to buy the "80's Glam" theme 24-pack I spotted in the supermarket!!

The next one I do I'm planning to etch control knob labelling. Tie-die might work nicely with that. Do you use primer at all? I did with the "granite" effect.

Right, you wanted gutshots - I'm afraid many feel ill at the sight of spilled guts, so you have been warned!! Also an aerial shot, to give an idea of major component layout. Component choice was mostly to do with available recovered parts!

Have you wired the master volume as in the HRM models? (If not the OD master output is usually switchable to the master volume input.) I was thinking the same thing about the MV setup but it looks like a global master after the loop perhaps? Yup - essentially the output volume from the "dumbleator"...

Guy77 wrote:Wow I thought my 16x8x3 in chassis was small !

The dimensions are 12 1/4" x 7" x 2 3/4"

What is the finish on the chassis? I wonder if that clear front panel is going to be OK so close to the power tubes . . . I guess you'll know one way or the other soon enough. The finish is "Faux-granite" using the guide at aronnelson.com The front panel is clear polycarbonate. It's made it through...

Schematics done. The different PAB arrangement isn't as flexible as I'd hoped it would be!

tictac wrote:I like the cabinet too; did you make a template to cut those oval shapes?

I used a zip saw when making cut in handles like that. Looks nice.

TT

I just used a hole saw for the corners and jigsaw in between:

Hi there, Here's my somewhat unconventional ODS build. I've put off posting for a long time as it's a bit (a lot) on the amateur side for this forum, but it makes me happy, so that's what's important, isn't it? I've realised while typing that I don't have an up-to-date schematic, so I'll try to put ...

It's already converted, and seems quite happy now. Or at least it did after I changed the PI output caps - one had gone short somehow, putting +135V at the grid of one KT66...

I'm thinking the fixed bias option is probably the best - top of p3 of the Genalex datasheet has almost the same conditions.

Shame I'd already ordered the 1k resistors...

Hi there, I've built an amp with a pair of KT66s cathode biased, and seem to have under-estimated the effect the screen voltage has on the current these things pass - they're dissipating more than they should be! Having looked back at the datasheet, I'm a bit confused as to how I missed it, as there...

Thoughts on switchable master volumes - just replacing the master with parallel switched pots will result in volume jumps on reverbs/delays/loops, so putting something before the FX loop makes sense... Given that the clean channel is quieter than the drive channel, an adjustable boost would be simpl...

Another question for them that have played with this circuit: The paralleled 500k pot // 560k resistors - is the resulting "taper" useful or would sticking a 250k pot in there be just as effective?