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Value of an old Gibson Amp, Keep or Sell?

Started by BigPolishJimmy, April 18, 2014, 12:25:41 PM

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BigPolishJimmy

I'm considering selling my old Gibson Varitone tube amp.  I bought this thing about 8 years ago as a project, but never really got around to it.  Money is always tight, I don't see that changing, and I'm contemplating selling it to finance a second Bandit112.

It came with a very large and very blown speaker, probably original equipment, but I plugged it into an 18" stereo speaker just to see if it had any go in it, and it did, but this was years ago when I first got it. 

I think if anyone wanted to use it, they'd want to consider replacing the caps as they're very old too.

...or should I convert it to a 12" Jenson and replace the caps and skip getting a second Bandit for my stereo setup?














Roly

This sort of decision is always basically a personal call, money, time, inclination.

(Provided that the power and output transformers are both in working condition) the major expense in order will be a new speaker, most likely new output valves, perhaps a new rectifier, maybe a microphonic preamp or two.

The main power supply electrolytics will almost certainly be due for replacement, and you are bound to find a few other items such as scratchy pots that won't clean up, and the odd cap and resistor.  All the pots, switches and sockets will need a liberal dose of contact cleaner.

However it is a Gibson Varitone, and it is a valve (tube) amp, each fairly desirable.  If it was working okay when it was put in storage then there shouldn't be anything too seriously (expensively) wrong with it.

Give it a bloody good clean with a vac and brushes and see how you feel about it then.

I'm biased, I always like to see old gear like this restored and gigging (but then I'm not the one doing it in this case).  The expense can be spread over time, as can the required work, so I'll encourage you to restore it.  I'd give the outside a good wash, glue down any covering that is lifting, but I'd leave it with its many dings 'coz I think they give it character.

Keep or sell you will get a fair bit more for it in going condition than as-is.

Do not power this up again without a limiting lamp.  I have just seen a case of a classic old amp really badly damaged by just "trying it out".


If you say theory and practice don't agree you haven't applied enough theory.

g1

As far as the speaker goes, replace it with the same size, and be sure to keep the original.  The original speaker can be reconed, and would be required for any serious restoration.
  If you want to use a different size speaker it would be best to build a new baffle.  Save the original baffle and speaker.
  To me it looks like the amp is bone stock.  Although it looks rough, it is probably a great candidate for restoration.
  If you can verify that it works, a buyer will at least know the transformers are good. Even though the speaker is blown, you could probably get a decent price from the right Gibson collector.  Get an idea of the recone price so you will be better informed when haggling over a price for the amp.

nashvillebill

Don't you hate it when great old amps (like this) appear to have been stored in a barn??  I mean, who decides "hey let's take this perfectly decent looking amp and carry it out to the chicken coop to store it"?  :(

My Epiphone EA-15RV (also made by Gibson, roughly same time frame) looked almost in the same shape as this amp.  I went the complete refurbish route: stripped and replaced the Tolex, stripped the chassis down and sandblasted it to bare metal, had it rechromed, replaced all tube sockets, even made a new eyelet board and repopulated it with everything new.  By the end of it all, the only things original were the wood box, the steel chassis (with its new chrome plating), the power transformer, and the reverb tank and switch.  I tried silkscreening new lettering on the chassis but couldn't get that process down so I stuck on labels instead, that's the only corner I cut.  Not counting the silkscreening effort, it cost a little over $100 for the chrome plating, maybe $75 for the Tolex and grill cloth, and maybe another $175 for the remaining stuff (OT, Garolite, pots, caps, resistors, knobs, sockets, etc).  I replaced the OT because the one in there was nowhere close to original so I used a Deluxe model from Classictone, it bolted right up to the existing holes.  I even replaced all wiring.

It sounds great now, no crackles or noises or hum, so the total refurb was worth it in my opinion.

Oh, mine had a unique way of shock-mounting the preamp tubes, they were riveted in place but through rubber isolation washers.  If yours is the same (I can't tell from the pictures), the rubber washers are available from McMaster-Carr, they offer a silicone hi-temp version.  Instead of rivets, I used #4-40 screws and nuts, then soldered the ground wires just above the nuts, the solder will keep the nuts from vibrating loose. 

nashvillebill

...I see on the last picture the preamp tube sockets are indeed mounted on rubber isolation washers, these are almost certainly dried/cracked/split and not functional.

I will also point out that I doubt I will recoup all of my refurbishment cost, should I decide to sell the amp.  Old Gibson amps don't quite have the appeal for collectors as the old Fenders.

Roly

#5
Quote from: nashvillebillDon't you hate it when great old amps (like this) appear to have been stored in a barn??  I mean, who decides "hey let's take this perfectly decent looking amp and carry it out to the chicken coop to store it"?  :(

Yes, I do.  I have had amps brought to me more than once covered with chicken poop and feathers.  I had one where several generations of native mice had been born and raised their own families in the reverb bag (but hadn't damage the springline), and still have a valve head I found in the powder magazine of a timber mill which had a large python living inside.

An amp apparently stored in the back of a fish and chip shop where it got covered in fat internally was bad, but the worst are amps and synths stored in a seaside garage or shed where the salty air has eaten the crap out of everything copper inside are the most depressing.

And almost always for something that would have originally been easy to fix.
If you say theory and practice don't agree you haven't applied enough theory.

JHow

I'd say get it working correctly and leave it cosmetically in its current funky glory. 


Sent from my iPhone using Tapatalk

BigPolishJimmy

Funky Glory is right.  Somebody painted this amp up to look like a Fender many decades ago. 

I was thinking of going with a 12" speaker with this because I have a 1/2 stack that I've considered parting out to more portable smaller amps.  Also the original speaker is huge, like 21" or something like that.  I know you can re-cone, but the spider also looks like it's going to disintegrate at the touch, and I'm not sure about that

g1

  The speaker is supposed to be a 15".  From the looks of other pictures, there's not really room for anything bigger in there.  Have you measured it?
http://www.chambonino.com/work/gibson/gib7.html
http://www.vintageguitar.com/16351/gibson-ga-80t-vari-tone/
  Anyway, if you want to put a 12" in there, you will need a different baffle, so keep the original intact with the original speaker.

J M Fahey

Everything can be repaired, even a burnt match, but it's up to you to weight value versus time, money and effort invested to achieve bthat.
I hate rust so I would dissassemble that amp in full, and I *mean* in full, have a tabletop worth of parts, all separate on their own, terminal strips, whatever.
then would replate all metal parts, silkscreen a new panel , ultrasonic wash knobs, etc. , clean/phosphate/repaint speaker frame, recone it (donĂ½ worry about the spider, "reconing" means replacing *all*  moving parts, etc.
I would end up with a practically just out of the factory amplifier.

Plan B would be just to wash it, repair what's needed, obviously retube and recone.

If you just want to play with it, fine.

If you plan on earning money on a resale ..... doubt it would cover expenses.
In that case I would wash the obvious grime, reassemble and sell as-is.

I bet some masochist out there will want it.