Marsha effects loop question

[mdc1mdc11]

Dave,

A couple of questions about the Marsha effects loop:

1) is it tube buffered driven or some other scheme? which pre-amp tube is assigned to the loop? Getting a bit of hum when the switch is engaged with effect active.
2) if tube based, what tubes work well there in your opinion?
3) using El Capistan and a wet reverb in the loop with short mogami cables. Do you recommend a DI for line level given the pedals input impedance?


thanks

 

[RACKSYSTEMS]

Most marsha's have a high voltage fet effects loop. Does your amp have a rtn level? Does the hum happen with nothing in the loop with the loop on? Sometime proximity of the cable and effects changes the hum.

 

[mdc1mdc11]

I think so, it has a push pull knob around the return jack that says "power amp volume, pull for loop". This is Marsha 50w number #49

Very small non-discernible level hum with nothing in the loop and push/pull switch off. When switch is on, fully clockwise, it is more pronounced. Wondering what I can do to calm it down.