Let's get the clarifications out the way first.  This amp has two names.  It's known as a Maestro Stereo 30 RVT and a Gibson GA-78RVT.  Whilst there were a few 78RV, the 78RVTs are the absolute rarest of entire series.  Gibson production records show that there were just four made, one in 1961 and three in in 1963.  One is known to have been destroyed.  All the parts in this amp date from late 1961 to early '62.  So it's probably a '62 that wasn't formally logged.  If I had listed this as a GA-78RVT you wouldn't haven't found it because even if you knew it existed you wouldn't have believed it was worth searching for.  The circuit is, however, identical to the GA-79RVT, which is the coolest and arguably the best, amp Gibson ever made.  The only differences are the Maestro cosmetics.   So, here you are, this the rarest version of the best Gibson amp.

Anyway, had to do some work on it over a long period of time to get it sounding right. The power supply, tucked away at the bottom of the amp, was a bit of a hazard, with semi-random, large, uninsulated components crammed into the box unsuccessfully.  Also, the cathode bypass caps and filtering cap were all out of spec, so I replaced these which massively tightened up the response and increased the output.  I also re-coned the two original Jensens because the spiders had come unglued and particle of perished rubber from the ancient flight case had got into the coil cavity!

I don't know what the say about the sound of this amp, really, it can be so many things, you can have it lush and spacy in stereo mode with the trem & reverb on or tight and punchy in mono mode with the effects off and pretty much anything in between.  It's a cliche, but it has to be heard to be believed.

Original Jensens, original footswitch, original transformers, original reverb tank.  This amp needs a UK transformer to operate at UK voltages, available on request.