Tube Amps / Music Electronics
|For current discussions, please visit Music Electronics Forum.|
|4/13/2003 4:23 AM|
||What to do with an original '55 5E3|
So, a friend brought me an amp to repair. It obviously needs a cap job. He thought it was a '53, but it's a very early narrow panel 5E3.
Anyway, it hasn't been touched inside. All components except tubes are original, but it's in pretty poor condition. My friend wants the cap job and he wants it to sound good again.
What's the best way to go about this? Is its poor condition enough that recapping it won't matter? Should I just do the caps? Should I pull the circuit board to place in a museum and make him a whole new circuit on garrolite?
He wants it as a player first, and not as a showpiece, but I feel weird about porking up a piece of history if that's what this is.
|And now, a word from our sponsors:
|4/13/2003 9:57 AM|
|Chris ( CMW amps )
Because of the value I should recap and retube the amp . Don't throw away the old parts . Getting the same e-caps would pretty dificult but some techs do put new-caps in the old caps-housings .
If the amp starts hissing at higher volumes some plate-resistors have to be changed ( original value but new resistors ) .
Hope Bruce can help too !!!
|4/13/2003 10:01 PM|
>Because of the value I should recap and retube
>the amp .
No offense, dude, but you aren't getting my work. If it gets a cap job, or anything else, the job happens in my shop.
I looked at this thing some more this morning and it's in sad shape. The owner tells me it sat in a warehouse on a concrete floor for a few years, and the warehouse was rather high humidity. The board is warped and looking icky at the ends, and you can spin the cardboard cases on the caps. I'm surprised it works at all.
At the moment, I'm really tempted to make a replica eyelet board out of garrolite, blueprint the thing by measuring all the resistor values, and then remove the entire circuit board in one piece to save for posterity. I could match the resistor values, use modern caps, and he'd be back on the road with a working amp, but I could put original components back in, easily. The only other change to make is a 3 prong cord with a proper grounding scheme as it still has a stock 2 prong and he's afraid he'll electrocute himself one day.
The owner wants this amp for a player, and though I've councelled him that I could build a brand new 5e3 replica for about $500 (CHEAP -- that doesn't come close to covering my labor), he won't budge. I'm still vascillating on the issues.
BTW, the guy picked this amp up for $150 4 or 5 years ago because some shop owner thought it was just an old "Piece of crap" thing. Go figure.
|4/13/2003 10:21 PM|
|Chris ( CMW amps )
">Because of the value I should recap and retube
>the amp .
No offense, dude, but you aren't getting my work. If it gets a cap job, or anything else, the job happens in my shop. "
Don't worry : shipping it to the Netherlands ain't cheap either , should have said "if I had to work on that amp" . I only wanted to help .
Your plan seems very good , hope you can make the owner very happy ( truly ! ) .
Driebergen , The Netherlands
|4/13/2003 11:39 PM|
|Bruce /Mission Aamps
If he's a player....I'd just unsolder the old ratty board and the yank it, buy a reissue eyelet board kit from WeberVST and repopulate it with all new parts. Stay away from carbon comp resistors and radial polypropylene coupling caps and use carbon film resistors with Mallory 150s... or the like.
Clean and relube the pots, clean the contacts on the switching jacks and use good NOS tubes if you havve them or modern tubes if you don't.
Done in 2-3 hours.
|4/14/2003 5:15 AM|
Sounds like a plan.
I talked with the owner this evening and he's oblivious to the historic value. He complained a lot when I told him I'd dated it to 1955 as he thought it was a '53 and was all proud that he had a '53 telecaster to match. Other than that, he said to do whatever I thought would get it back to sounding good.
I roll my own boards, so there's no need to buy one. A friend made me a great eylet staking tool that I've been itching to try out, so this is a perfect project.
And I don't care for carbon comp, nor do I buy into the carbon-comp mojo thing. I've had great luck with metal film in my last 2 builds. I see you ship kits with Carbon Film, though. Any reccomendations on brands or suppliers? And is it worth it to get them special over using the BC metal films I've got?
|4/14/2003 6:06 AM|
|Bruce /Mission Aamps
Metal film resistors are just fine too.
You can get almost everything you need for a complete rebuild (Sprague ATOM filter caps to axial polyester coupling caps), from Mouser.
I like to use 5k1 2w and 22k 1w flameproof metal oxide resistors in the power supply B+ rail.
If you make your own boards, bring the eyelets a little closer together across the narrow side of the eyelet boards.
Modern resistors are about 1/4" to 1/2" shorter in lead length then vintage carbon comps and they will not fit straight across and stil have enough lead length to go all the way through the eyelets.
|Page 1 of 3||Next>||Last Page>>|