So you guys that are doing JM Sig builds...

[pinkphiloyd]

...what kind of speakers/cabs are you running? I'm planning on doing one in the near future (if I can talk my wife into it) and I'm just thinking ahead a little.

[M Fowler]

Either WGS ET-65's or EVM12L's in Dumble 212 cabs either cab sounds great.

[beasleybodyshop]

I am running a pair of Eminence EV12 clones, they are the EM12s. Similar sound. Works great. Good luck on your build!

[pinkphiloyd]

I was thinking WGS ET65's. If I decide to go all out Scumback makes an equivalent and I've had great luck with his speakers in the past. I was more curious about cabs. Anybody have any experience with Lamar by any chance?

[pinkphiloyd]

As long as I'm asking questions, are these the most recent schem and layout? Seems like I read there might have been an issue with the layout. Was that remedied or should I double check this layout? (I know I should just out of principle but I'm just curious.)

the schematic shows the switch
https://tubeamparchive.com/download/file.php?id=30388

and beasleybodyshop's draft layout shows the pot correctly (I think it's missing the one jumper on the switch tho):

https://tubeamparchive.com/download/file.php?id=37515

[beasleybodyshop]

Layout is just for parts reference. It is not 100% correct. I haven't got around to fixing it. I should though. Ive had several people message me complaining of issues with their build. This is definitely not a solder by numbers amp.

I should probably just pull the layout until i get around to completing it.


Yes please refer to the schematic.

[pinkphiloyd]

That's cool, I can handle the layout. Thanks.

[amplifiednation]

A pair of Celestion Golds is pretty awesome...but a LOT of cash.

[pinkphiloyd]

A pair of Celestion Golds is pretty awesome...but a LOT of cash.

I've never really been an alnico speaker fan for some reason.


Where can I go to learn about reverb? I understand the basics. Take part of your signal, amplify it enough to drive it through the springs, recover it on the other side and blend it back in to your signal. But that's pretty much the extent of my knowledge. So say I wanted to tweak this circuit. Is there a resource I can use to begin understanding how I would go about that?

[M Fowler]

I like alnico speakers with non reverb amps because these speakers to me give off a reverb quality which I don't understand. Heck I don't understand most of what I've noticed about amps.

Try a Trainwreck Rocket through Celestion gold or blue and if that doesn't impress you nothing will.

[beasleybodyshop]

A pair of Celestion Golds is pretty awesome...but a LOT of cash.

I've never really been an alnico speaker fan for some reason.


Where can I go to learn about reverb? I understand the basics. Take part of your signal, amplify it enough to drive it through the springs, recover it on the other side and blend it back in to your signal. But that's pretty much the extent of my knowledge. So say I wanted to tweak this circuit. Is there a resource I can use to begin understanding how I would go about that?

You pretty much explained the gist of it. Signal going to the reverb tank needs an impedance change for the transducer in the tank. Start with a blackface AB763 fender schematic and study the reverb circuit from there. Another good circuit to look at for study is the fender standalone reverb units, Gibson GA series amps with reverb, etc. Compared to the fender standalone reverb unit, you can see what things in the circuit affect the tone, drive, etc.

[pinkphiloyd]

A pair of Celestion Golds is pretty awesome...but a LOT of cash.

I've never really been an alnico speaker fan for some reason.


Where can I go to learn about reverb? I understand the basics. Take part of your signal, amplify it enough to drive it through the springs, recover it on the other side and blend it back in to your signal. But that's pretty much the extent of my knowledge. So say I wanted to tweak this circuit. Is there a resource I can use to begin understanding how I would go about that?

You pretty much explained the gist of it. Signal going to the reverb tank needs an impedance change for the transducer in the tank. Start with a blackface AB763 fender schematic and study the reverb circuit from there. Another good circuit to look at for study is the fender standalone reverb units, Gibson GA series amps with reverb, etc. Compared to the fender standalone reverb unit, you can see what things in the circuit affect the tone, drive, etc.

I missed this, but thanks. I've pretty much been doing this and studying the JM schematic. I want to "get it" before I build it.

Regarding that, am I missing something? Should there be a switch to ground the grid of the recovery tube, maybe, when no 'verb is desired? Or is the premise that one would simply turn the send and/or return all the way down? It seems to me that that might lead to signal loss that you wouldn't get if you had the option to ground the grid of V2A or V2B? I'm probably missing something or overthinking it.

[amplifiednation]

If you wanted to switch the reverb off you could just toggle ground on the reverb return jack. You could put it on a relay if you wanted. I'm sure there's a million ways to do it but that's one way.

[BarryW]

For another flavor - mine sounds great with JBL K120s. Just a beaut with a strat for Dead ...

[pinkphiloyd]

I've purchased a couple of Eminence Legend EM12's in anticipation. My first Eminence speakers. Hopefully they live up to the EVM standard.