Heretical Build

memphis032 · Post by **memphis032** » Mon May 25, 2015 9:31 pm

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 that together tomorrow. I'm also a lot embarassed by the mess that is inside the thing, so no gutshots today. The outside is here though!

The chassis was my first attempt at sheet metal folding (well, was one of a batch of four I did, anyway), and didn't go too badly. It is the same size as an Epi Valve Jr chassis.

The sleeve is made from an oak tabletop we had delivered by mistake, and they didn't want it back when they delivered the correct one...

PT is a Mojotone 758EX Vibrolux/Tremolux, OT is a second-hand JTM45 with 7k5 primary for a pair of KT66s.

Last year it had parallel input triodes, a cathodyne P.I. and cathode biased output valves, but that wasn't a good experiment, so the preamp is now more conventional non-HRM low plate, apart from the boost (will be clear when I've done the schematic), with bluesmaster P.I. values.

The reasons behind my choices were mostly to do with reading posts here to find what seemed to work for which guitars and styles, and tryiong to come up with a good compromise for my own playing. I'm not after a perfect clone which requires a seperate Dumbleator and exact length curly Loop cable to sound right, but something which is practical for live playing where most won't hear the difference.

I hope the somewhat compact build will be interesting rather than offensive to folks here!

tictac · Post by **tictac** » Mon May 25, 2015 9:46 pm

I like it....

I built a non-standard ODS myself... tubes up like yours

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

romberg · Post by **romberg** » Mon May 25, 2015 9:47 pm

I'm currently working out how to fit all of a HRM into a small sized chassis. And your's is even smaller than the one I'm using! I think it looks sweet. I'd love to see how you arranged things inside (no need to be bashful). How does it sound?

Mike

10thTx · Post by **10thTx** » Mon May 25, 2015 11:19 pm

I like it! I hope you will post an interior chassis shot whether it looks "messy" or not.

Any chance of a sound clip?

with respect, 10thtx

drew · Post by **drew** » Tue May 26, 2015 12:24 am

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.

vibratoking · Post by **vibratoking** » Tue May 26, 2015 6:00 pm

I love your concept. That's a damn small chassis. I really like the clear front panel too.

By the way, I don't think you need the Dlator to get the 'true' Dumble sound, whatever that is. Others will disagree. I happen to like the increased clarity without the Dlator, but it does depend on what, if anything, that you put in the loop. The Dlator helps with certain effects and loading.

Guy77 · Post by **Guy77** » Wed May 27, 2015 1:56 am

Wow I thought my 16x8x3 in chassis was small !

Great build!

Guy77
Keep the iron hot

memphis032 · Post by **memphis032** » Wed May 27, 2015 9:07 am

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:

memphis032 · Post by **memphis032** » Wed May 27, 2015 9:52 am

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

bluesfendermanblues · Post by **bluesfendermanblues** » Wed May 27, 2015 1:32 pm

memphis032 wrote:Schematics done. The different PAB arrangement isn't as flexible as I'd hoped it would be!

Great looking lunchbox-size amp! Build for live usage.

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.)

memphis032 · Post by **memphis032** » Wed May 27, 2015 1:54 pm

drew wrote: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 a few hours of use so far with no noticeable change, but time will tell!

memphis032 · Post by **memphis032** » Wed May 27, 2015 1:58 pm

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

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

David Root · Post by **David Root** » Wed May 27, 2015 10:36 pm

Remarkable job! Very nice woodwork, you must have done that before.

If it doesn't hum in a tiny chassis like that your wiring is OK, even if it doesn't look too tidy to you (we haven't seen it yet!).

Smokebreak · Post by **Smokebreak** » Thu May 28, 2015 12:15 am

bluesfendermanblues wrote:
memphis032 wrote:Schematics done. The different PAB arrangement isn't as flexible as I'd hoped it would be!
Great looking lunchbox-size amp! Build for live usage.

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?

stelligan · Post by **stelligan** » Thu May 28, 2015 1:42 am

Cool Cab! Cool paint job, Cool build!

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