Check my new amp out! Gibson GA-18

[leaveitalone84]

http://cgi.ebay.com/ws/eBayISAPI.dll?Vi ... 0247748603

Looks cool, I'll let ya guys know when It arrives.

Edit: On closer inspection it looks like that mass of electrical tape is a mod of some kind. Oh well, i'll strip it down to factory!

[bnwitt]

Looks like that might be a can capacitor

[leaveitalone84]

Yeah, it looks to have had a cap job done in the past. Well no reason to not do it right this time.

[billyz]

Nice Score! Should be no problem to restore that baby.

[skyboltone]

Yeah baby:
Mojo!

[Firestorm]

I've got one of those. Pretty cool amp -- a little like a Tweed Deluxe, but with a 10" speaker. Also, unlike a Tweed Deluxe, it has a negative feedback loop. I disconnected the loop on mine and now the amp gets up and dances around the room. Try it -- easy to reconnect if you prefer it cleaner.

[leaveitalone84]

So I just got the amp today. Here's the rundown.

1) It smells like basement...was expecting it. But the cabinet is really solid.
2) The speaker has rips around the surround and the cone is actually ridiculously warped.
3) Tube sockets are looser than a..i'll keep my language clean.
4) Lame filter cap job.
5) There was some mods done to the output section. The wiring doesn't match the schematic. I think someone was trying to get it quieter.
6) The pots and jacks are all perfect! No noise!
7) Besides the 6V6's it's all vintage glass.

So heres what I plan to do.

1) I'm going to do the Princeton type job and put in a new baffle with a Weber 12". Something along the same line as the original Jensen. I'll get the original 10' reconed eventually so I could have the option, but I love 12's.
2) Recap, retention sockets, and bring it back to stock.

Firestorm, I assume I could even throw in a switch for the NFB and stuff?

[leaveitalone84]

double post

[Firestorm]

Firestorm, I assume I could even throw in a switch for the NFB and stuff?

Yep, I did that for another guy who has one. I didn't want to drill a hole so I epoxied a mini switch to the bottom of the chassis. NFB vs. no NFB: best of both worlds. If you have an amp with a 10" alnico in it, you might want to see how it sounds through that before committing to a 12".

[leaveitalone84]

Firestorm, I assume I could even throw in a switch for the NFB and stuff?

Yep, I did that for another guy who has one. I didn't want to drill a hole so I epoxied a mini switch to the bottom of the chassis. NFB vs. no NFB: best of both worlds. If you have an amp with a 10" alnico in it, you might want to see how it sounds through that before committing to a 12".

I was thinking of throwing my NFB with a push/pull pot, I've seen that on a few custom DIY fenders around the net.

Unfortunately I don't have a 10" alnico right now. Id figure with a 12" though its going to sound a lot like a deluxe or brown princeton.

What strikes me sideways is how small the OT is on this amp. How loud is yours? There's something going on in mine as dimed its no louder than a cough. So I have to trouble shoot it.

[CaseyJones]

Firestorm, I assume I could even throw in a switch for the NFB and stuff?

Yep, I did that for another guy who has one. I didn't want to drill a hole so I epoxied a mini switch to the bottom of the chassis. NFB vs. no NFB: best of both worlds. If you have an amp with a 10" alnico in it, you might want to see how it sounds through that before committing to a 12".

I was thinking of throwing my NFB with a push/pull pot, I've seen that on a few custom DIY fenders around the net.

Unfortunately I don't have a 10" alnico right now. Id figure with a 12" though its going to sound a lot like a deluxe or brown princeton.

What strikes me sideways is how small the OT is on this amp. How loud is yours? There's something going on in mine as dimed its no louder than a cough. So I have to trouble shoot it.

A couple notes: I'd fix it and I wouldn't mod it. These are following the tweed Fenders up in value, stock or restored to stock is worth much more than modded.

If it you have no idea what it sounds like when it's working properly it's too soon to think about mods.

These amps sound dark in stock condition through the stock speaker. A lot of guys buy 'em 'cuz they think they're Gibson's take on a tweed Deluxe, then they mod the nuts off 'em 'cuz they sound nothing like a tweed Fender. I stuck a Weber Blue Pup in the last one I had. A new Blue Pup costs about as much as a nicely preserved 10" Jensen. The tens bring good money because they're rare compared to 12" Jensens, also a lot of guys are lookin' for the tens for Bassman or Bandmaster replacements.

[leaveitalone84]

Hey Casey,

Yeah, I plan on getting her up and running stock before anything else. I have all the filter and cathode caps on order along with the cathode resistors (sticking with the carbon comp).

The NFB switch will be reversible if I end up doing it. Thats why I'm making a replacement baffle too so I wont screw up the original with a 12"

The original Jensen's cone is destroyed so It's either get it reconed now or just throw in a new speaker for the time being. Since its cheaper for me to get a new speaker....I'm gonna do that till I have the money to get the original fixed.

I've seen to much bastardized vintage gear to forever ruin a good one!

I was looking at the Weber 12A125 and 12A125-O. The "O" version is listed as being warmer sounding, more aggressive, and punchier than the plain 12A125 which is a favorite for Deluxes, what would you recommend Casey? I want to stay away from the British Style speakers in this amp.

[Jammin'John]

The 12F150T,25w would be sweet !
http://taweber.powweb.com/weber/12f150t.htm
If you want some volume Ted can put a larger magnet on it.
You don'y need alnico compression on a low power amp !

JJ

[leaveitalone84]

So I went through the amp this past weekend.

I replaced the power cord for a proper ground, cleaned most of the connections. I added in a speaker jack for the OT and cleaned up the hacked trem jack.

I replaced the filter can cap and the cathode caps/resistors.

This amp SMOKES plugged into my 2x12 Weber Blue/Silver Alnico open back cab. Harmonics up the ass and touch responsiveness galore. Great blues/rock/country amp.

Trem circuit still needs a little work but sounds good. I also placed in a push-pull pot on the Tone knob to disengage the NFB. Switches this baby from GA-18 to Tweed Deluxish. Killer!!!!

Waiting for my Weber order now

[jjman]

Not sure what the giant Astron cap is functioning as but they are known to leak DC after time. I found 7 of 8 to be leaking DC in my freind's old Ampeg.