Jtm45 head into jtm50 combo

[Alshaheen]

Could someone please help... I have a jtm45 head that i run into a Jtm50 combo...plugging into the speaker... is it possible to have the speaker plugged into the jtm50 and the jtm45 selecting the source only by which is amp powered up?... So meaning both will be connected by a Y type plug to the speaker.... Hope i made myself clear

[pompeiisneaks]

It's dangerous to do that kind of thing, because both amps will want to see a load when 'not connected'. In theory if you built a switch box that swapped the 'not used' amplifier to a 100-200W 8ohm resistor (or whatever impedance they want to see) then you can protect the other amp from being destroyed.

Hope that makes sense. You cannot leave an amplifier with tubes not connected to a load of some kind. Usually it's better to switch the guitar output into two amps with a/b pedal and have both amps with cabinets. Not sure if you're mostly trying to not have more cabinets. Also, the jtm45 and 50 are basically the same amp except one is a head and one is a combo. What specifically do you find 'different' between these amps? So far at my review the only difference is the JTM50 seems to have more filtering in the power supply 32uF vs 16uF... (I'm looking at some marstran schematics, not sure if they're authentic. )

Edit: I did find one other major difference, the 45 is tube rectified and the 50 is diode rectified... so sag may be a differnece there, i.e. 50 has a very stiff power supply and 45 not so much)

~Phil

[pdf64]

is it possible to have the speaker plugged into the jtm50 and the jtm45 selecting the source only by which is amp powered up?

It doesn’t seem a good idea to drive one amp into another OT.
If nothing else, a ground loop might be created, unless the power cable of the inactive amp is removed from the wall outlet.