The Amp Garage

Fixed the links, working on my side.........

Here's a little of me diddling around

https://www.youtube.com/watch?v=O7Auic7wG84

Ok here's a video, my first one so be gentle on the quality and the playing.

Not sure it if it captures the amp, I make do another one.....

https://www.youtube.com/watch?v=snruyEdJN88

Considering Randall Smith has serviced the amp, I'm looking for mods............

Other than all the 100K resistors are 1 watts I'm not seeing much, but I'm not much of a mod guy.

For those that are interested, here's some better shots of the main board.

Deric, I think the 20uf might tighten things up slightly but I don't think it will make a big difference. I personally prefer to keep vintage amps as stock as possible, so I would lean towards the 16uf. I am curious, is the 47pf bright cap still on the vibrato channel volume and is there any change...

modman wrote: ↑Fri Jan 19, 2018 9:03 am As far as the coupling caps go -- you can easily check how they are doing by checking for DC leakage.
If there was smoke, it's more probably a burnt resistor than a capacitor.

Are there pictures of Jerry playing this amp?

The source of the smoke:

Got it! Probably why Dumble moved on from them after the “pre-production” era.. ??? Dumble has always been a 6PS man. Not really. Check Odyssey, Winterland and pre production ODS You're right. I tend to think of those amps as one offs and the efforts of a young Dumble finding his niche. Once he fou...

That is a cool idea. Keep us posted!

Woo Hoo! Very nice looking cab, too, well done! I guess that obviously bad tube was hiding on the other side of the chassis, just where you couldn't see it. So, how is the UL sounding to you? Is the presence effective? You might want to experiment with the GNFB level (varying the FB resistor) to se...

Ta Da!

IT"S ALIVE!!!!!! The beast lives! Found a stray wire from the stranded wire input into the filters, one little fiber taking out the signal into the filters. All issues fixed, presence work well, FET works well, filters are GREAT (go Martin!) very usable frequency shifts. Cabinet is ready! Happy!

So ................ I was happy to find this. The source of silence.

With the CF replaced, I still have and amp which seems to be giving me only the reverb signal.

All of the control on the front panel for with the exception of the filters. At least I know where to look.

Bombacaototal wrote: ↑Wed Jan 17, 2018 6:40 am

dreric wrote: ↑Wed Jan 17, 2018 4:53 am

Bombacaototal wrote: ↑Tue Jan 16, 2018 6:22 am

Hi Dreric, why are the choco drops dreaded?

Of all the Fender caps they have the most controversial reputation. My goal with this amp is to leave them alone.

Got it! Probably why Dumble moved on from them after the “pre-production” era..

??? Dumble has always been a 6PS man.

From your description, the signal could be grounded out at the filter output, which is where you were working. Maybe the shielded cable is shorted? Check the resistance to ground. I check in and around the filters, all good. I did find 2 pins on V2 that I neglected to solder. Quickly fixing those I...

Bombacaototal wrote: ↑Tue Jan 16, 2018 6:22 am

dreric wrote: ↑Sun Jan 14, 2018 3:00 am ... The dreaded chocolate drops are present..

Hi Dreric, why are the choco drops dreaded?

Of all the Fender caps they have the most controversial reputation. My goal with this amp is to leave them alone.