1. stratocat63

    stratocat63 Member

    Messages:
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    Murrell's Inlet, SC
    I've been going through my amps, a few of which have been stored unplayed for years and need to find someone with knowledge of the 1955 Bassman.

    First, the tube chart is gone so I'm not sure which circuit it is, but it's got to be either 5D6-A or 5E6-A (two rectifiers) (?). The preamp tubes as far as I can figure should be 12AY 12AY 12AX/7025, I have one 12AY7 in the first position, 12AX7s in the others. Back in the day when I used to play it out an amp tech told me to swap the 12AY7s out for more gain, and I only had one extra 12AY7 on hand today.

    I'd appreciate it if anyone who has owned or serviced one of these to offer some opinions on what tubes they liked best in them.

    I'm wondering if it's okay to drop a 5u4 and go with one for a little more sag if desired.

    Alas, I blew the original speakers years ago but still have them. If I can get the money up (amp rich, cash poor, but am not selling any of them at this time), who would be the best person to speak with about re-coning them? Btw, have Mojo Tone MP10-Rs in there now and they sound pretty good.

    Got some problems with a couple of the pots, the place I had the amp stored in wasn't the best place for it, a source for replacements would be nice.

    In spite of the oldness and storage and pot noise (the Treble doesn't even work) the amp sounds darn nice. Better than I remembered.

    Looking forward to hearing from someone familiar with these, thanks in advance.

    PS:

    A really great thing would be if someone out there can run a Texas DL number, there's one engraved on the control panel. Be neat if it was someone I'd heard of. This, I realize, is not an easy request to fill and very unusual, but I've been curious ever since I've had it.

    PS#2:

    Also, I was told a story about this amp when I bought it (Eugene's): back in the day when the rough brown Tolex replaced tweed Fender had a promotion which was: send the amp back and get it recovered in the "new" covering, plus new speakers, for $150. Sounds kind of shady, but then 3 of the speakers had '59 date codes and 1 had '55 (meaning, maybe one of the '59s blew and the owner put one of the originals back in, that would make sense. Also, the time Fender switched to the rough brown would coincide with the speaker dates, '59s would have been on hand around then). If any of the gurus out there have ever heard of such a thing, please speak up! The re-cover does look very "factory" in quality, to my untrained eye.

    The originality isn't that big a deal to me personally, since I bought it to play not to collect, but maybe I'd want to sell it one day. I've had the amp for about 17-18 years.
     
  2. booj

    booj Member

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    Jan 18, 2008
    I've got the schematic but I need to go through photobucket to post it 'cause it needs a URL. I haven't posted any pix on this site yet. Don't know how. duh
     
  3. stratocat63

    stratocat63 Member

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    Hey booj, thanks. I have found the schematic since I posted, so don't worry about uploading.
     
  4. Monroe

    Monroe Guest

    Get Ted Weber to do the re-coning.
    Have you checked at the Fender Amp Field Guide?
     
  5. stratocat63

    stratocat63 Member

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    I heard Weber doesn't re-cone any more (maybe wrongly?), guess it wouldn't hurt to ask.

    Field Amp Guide is great but doesn't really tell much I don't know about the amp, was hoping for an owner or person who's serviced them to pop in.

    In any case, thanks for your help.
     
  6. Wakarusa

    Wakarusa Member

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    It should be pretty easy to figure out if you've got a 5D6-A or 5E6-A. The simple differences are in the phase inverter (5E6-A used 56K plate/cathode resistors, 5D6-A used 47K plate/cathode resistors) and the bias supply (5D6-A has a 6K8/47K voltage divider, 5E6-A uses 3K3/56K).

    The original used 6L6G output tubes - not so easy to find. You can run 6L6GC, but for current production the Russian Tung Sol 5881 is, in my opinion, your best bet.

    Unfortunately, again in my opinion, current production 12AY7 either don't sound good, are microphonic, or both. A nice set of NOS RCA, GE, or Sylvania 12AY7 are all good, but expensive and can also be microphonic. For current production tubes, I've found that the Russian Tung Sol 12AX7 in all three slots works pretty well -- I've found this combination gets you a decent balance for gain and doesn't end up overly bright (which is easy to end up with using other stuff). 'Course the best rule is try any ol' thing you have in stock and see what you like best.

    It'll run on a single 5U4 just fine. You may also like a single 5R4. In any case you should consider making the bias adjustable, but especially if you're going to mess with the rectifiers.
     
  7. stratocat63

    stratocat63 Member

    Messages:
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    Murrell's Inlet, SC
    Thanks very much for the information Wakarusa, appreciate your time.

    I did find another 5U4 I had stashed away so there are now two in the amp.

    I'll be swapping out some tubes to see what sounds better, I can rob a 12AY7 from another amp to listen to. And I have a gazillion Sovtek and Ruby 12AX7s around but can also take some more vintage tubes from other amps to try out.

    I have an old pair of GE 6L6GCs pulled from another amp, I'm guessing '60s, and a pair of the recent Tung-Sol 6L6GC-STRs. The amp has Sovtek 5881s in there now, probably about ten-twelve years old.

    May as well ask opinions on running three speakers vs four, cool or not?
     
  8. Wakarusa

    Wakarusa Member

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    Three vs. four speakers isn't such a great idea. Also the Sov 5881s probably aren't the best choice for this (or most :)) amp(s). Electrically it's only marginally like a true 5881 and in terms of tone/dynamics very different.
     

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