Marshall JCM 800 ”dual” footswitch wiring help

[jettrocker]

Hi. I need a footswitch with one switch that changes channel on two Marshall JCM 800 amps at the same time.
I found a schematic of a singel one and just added one more mono jack for the second amp.
Will this work? Or will I run into ground loops or other problems?

[PRR]

You might have trouble.

A 3P2T switch allows each amp to be completely separate.

[Hatredman]

Which JCM800? The Lead, The Split Channel, the Solid State or the Bass one?

We need to look at the correct schematic to answer your question.

[jettrocker]

Which JCM800? The Lead, The Split Channel, the Solid State or the Bass one?
We need to look at the correct schematic to answer your question.

Its JCM 800 2205. 50 watt with boost channel and reverb.
Im not using the reverb so the only thing I wanna switch is between normal and boost channel.

[Hatredman]

Have you checked the schematic ?

[Hatredman]

http://www.drtube.com/library/schematics/69-marshall-schemas#JCM800

[jettrocker]

http://www.drtube.com/library/schematics/69-marshall-schemas#JCM800

Im sorry but this is my first DIY build so looking at the amps schemas won't help me... Cant understand them.

[composition4]

Jettrocker if you do run into problems with running both with your configuration, use the bottom 4 lugs on your DPDT to control the two amps totally separately, and use something similar in principle to one of RG's Millenium bypass schemes on the spare lugs for the LEDs. Search the forum or geofex.com if you don't know what that is.  Yell out if you need help implementing this

Jonathan

[PRR]

Doesn't a 3 pole 2 throw (even 1-throw, but that's not standard) switch give:

* complete isolation one amp to the other
* complete disregard for schematics and thinking

??

jettrocker believes his plan IS correct for one amp. I suspect this may be true, and am not inclined to "think" about what whack Marshall put in their too-too-too-many amp models.

Given that...

jettrocker thinks his plan would work for two amps. I agree only that it "may" work for two amps, with an obvious risk of signal ground-loop.

If switches were ONLY 2 Pole, we might have to "think", even "schematic".

But the 3P2T switch is now VERY common in Stomp-Land, and available at any stomp-box supply store, and from switch specialists (B**ches L*ve My Switches, etc), and even lately a few at the "real" chip-houses (Mouser, DigiKey, et al).



So.... think, ***OR*** blow $5 for a switch is which very sure to work (if jettrocker is correct that a 1P1T switch will flip one amp; a 2P1T for amp+LED).

I'm a thinker, but many days I'll throw $5 to avoid having to think excessively.

[jettrocker]

Thanks for your help!!!

Doesn't a 3 pole 2 throw (even 1-throw, but that's not standard) switch give:

* complete isolation one amp to the other
* complete disregard for schematics and thinking

??

jettrocker believes his plan IS correct for one amp. I suspect this may be true, and am not inclined to "think" about what whack Marshall put in their too-too-too-many amp models.

Given that...

jettrocker thinks his plan would work for two amps. I agree only that it "may" work for two amps, with an obvious risk of signal ground-loop.

If switches were ONLY 2 Pole, we might have to "think", even "schematic".

But the 3P2T switch is now VERY common in Stomp-Land, and available at any stomp-box supply store, and from switch specialists (B**ches L*ve My Switches, etc), and even lately a few at the "real" chip-houses (Mouser, DigiKey, et al).



So.... think, ***OR*** blow $5 for a switch is which very sure to work (if jettrocker is correct that a 1P1T switch will flip one amp; a 2P1T for amp+LED).

I'm a thinker, but many days I'll throw $5 to avoid having to think excessively.