This old warhorse is in overall excellent condition. Let's see what it needs to really shine. For more info, Subscribe to this channel, join us at PsionicAudio, or email us at info@psionicaudio.com.
You are ticking my boxes! I have one of these variations-55’ GA45 which is quite similar. Had it serviced but the tech didn’t address the bass and treble which has very little effect on the amp’s sound. Also he didn’t change the input resistors to reflect the GA-40. That one sounds great, mine could stand a bit of improvement. Gets quite hairy past 3-4. Just know there is a beauty queen lurking inside. Wish it had come with the 4 -8” Jensen gold alnico’s. Do you know the story on these GA45’s -made for accordion or harp? Don’t see many and haven’t found out who the audience was for this model. I know that harp players seem to love them. With your last comment about caps on the backside, that shakes a memory and may explain why he didn’t go digging. He probably didn’t want to frighten me with the bill to move those caps to the top of the board but I got it for a good deal, no Jensen’s but an Altec 417-8C if memory serves me. It had seen better days and I put a Reconed Rola. Still working on bringing it up to snuff. Thanks for your content.
I’ve reinforced spit shafts with a plastic or wood shim to use with set screw knobs a few times. It could be more trouble than it’s worth on this one if the pots aren’t all that great to begin with, though. You also still have to be careful not to over tighten them and put divots in the teeth. The amp sounds great!
I’ve used brass conversion sleeves on this type of job and they worked very well. Don’t know if they’d work perfectly with these knobs or not but they should at first glance.
Doing more research, looks like Gibson shipped the amp with press on knobs similar to what's on Les Paul guitars from this time. But those are long gone, and these chickenheads are pretty old themselves. So I'm ordering some brass sleeves to protect the two original split shaft pots.
It sounds a lot like my 5E9 Tremolux. (Oct. 55). The tremolo is especially nice. Do the volume controls interact the way they do on a Fender? I'm not too familiar with these. I've seen them but never played one. The sound is golden.
Love these videos I've been getting a lot out of watching and learning. I'm new to amp work (I do have some electronics training and understand how to stay safe while working on an amp) and I'm rehabbing a old Gibson Falcon and the tremolo makes a similar ticking noise as the amp in this video. When I heard it I got little excited because was anticipating a segment about fixing that noise. Is the ticking just a fact of life and there's no way to fix it? I can't seem to find much info about ticking tremolo where the Fender optocoupler isn't the source. Any words of advice would be much appreciated. Thanks for all the great videos!
A friend down in Tucson has the script grille '54 with the octal pentodes (6SJ7, IIRC). Great little amp. Uses a third 6V6 to yank on both the screens and cathodes of the push-pull pair to make the tremolo go.... He is thinking of selling it, and has said he will give me first shot at it....
