got a bassman135

Discussion in 'Amps and Cabs [BG]' started by jmpiwonka, Feb 25, 2006.

  1. jmpiwonka


    Jun 11, 2002
    it sounds prety badass, i have one problem though....well two.

    i need an eyelet for the power bulb, and the three position toggle switch close to the on and standby toggles is missing the paint on it....i'm guessing it is the impedance switch.....and it moves horizontal.
    i need to know what position is for what.

  2. ttyR2


    Feb 23, 2003
    Athena, OR
  3. jmpiwonka


    Jun 11, 2002
    oh sweet, i was looking for diagrams through google because i didn't think i would find any good pics on ebay...had no luck.
  4. Eric Cioe

    Eric Cioe

    Jun 4, 2001
    Missoula, MT
    That swtich is probably a polarity switch. If yours has been modded with a 3-prong plug, it probably doesn't matter what it does. Mine has been in the middle since I bought it (Bassman 100 - yours with a different transformer, basically), and I've never felt the need to mess with it.

    You ought to try jumping the channels - plug into bass input 1, send a short cable from bass input 2 to regular input 1.

    Also, what tubes are in it right now?
  5. jmpiwonka


    Jun 11, 2002
    i don't even know what tubes it has, i just got it yesterday.
    i'm kinda curious about that. i can turn the cahnnel and master volume all the way up and it stays is loud as **** though...and that's through my acme low B2.
    my neighbor is an amp tech and knows all about tube heads and he told me it sounds strong, but he said it should start to break up around 3 on the master volume if i turn the channel all the way up.....he came over because he heard it while me and my brother were playing.

    also the bright switch doesn't work on the normal channel, but everything else does.

    how do these regulate impedance rates....does it do it automatically?

    also what is considered flat on these?
    is it bass at 2, mid at 10, and treble around 2 also?
  6. Eric Cioe

    Eric Cioe

    Jun 4, 2001
    Missoula, MT
    I've always assumed so - there isn't a switch or anything. Mine says "4 ohms total impedence" on the back, so I always run mine at 4 ohms. I would like to try it at 8, though, but have been nervous about it.

    Yes. My favorite settings are, with the channels jumped, bass boost on, bass on 4, treble on 2 (no mids on the bass channel of a 100), and on the other channel, bright off, bass 4, mid 10, treble 2. Set the channels volumes around the same, master wherever you need it. This head rips.

    You should take the back off and look at the tubes. It should say right on them what they are. Mine actually had some original USA labelled 7025s, I think, in the preamp, which I've replaced with NOS JAN GE 5751s. The driver tube was a USA 12AT7, but I replaced it with a NOS Mullard. The amp got a lot quieter, but the gain with the channels jumped is far more under contral now.
  7. jmpiwonka


    Jun 11, 2002
    eric i just took a look.
    there are two relistic 6L6GC's, one more 6L6GC that that reads something..dc and then says USA on it....and the last power tube i cannot read at all, the label is on the far side.

    here is what the tubes look like.
    the one on the far left of the pic is the one that looks a little different...well the size is the same but the internals of the tube are a little different. look towards the tip of the tube and you will see. i don't know if that means anything.

    i didn't want to mess with the tubes or anything as i know the job of a capacitor and i'd rather not feel what they do.....:)
    how do you discharge them anyway?

    oh yeah, pic.
  8. ibz


    Apr 14, 2005
    Columbus, OH
    It seems like your power tubes are 2 different pairs put in there. There's a pretty good chance if thats the case that a matched quad should get you a better sound if they're biasd correctly.
  9. jmpiwonka


    Jun 11, 2002
    yeah i was just looking into that.
  10. Skel


    Jun 19, 2005
    Boulder, Colorado
    I thought you guys might get a kick out of this. It's an excerpt from an e-mail thread I had going with Carol Kaye, the legendary LA studio bassist. I was asking her what amp she used, assuming it was a bassman, and here's what she had to say:

    ">>>Fender bassman with an open back 4X10 cabinet<<

    NOT AT ALL, it was a Fender Super Reverb with 4-x10s I used - good low-powered amp (studios required low-powered amps, not stage amps at all) but had to stick matchbook covers in to keep the back panels from rattling....the Fender Bassman was a TERRIBLE amp, awful amp. I used always the Versatone amp from about 1966 on...enclosed cab 1-12."

    Well, that's *her* opinion.

  11. jmpiwonka


    Jun 11, 2002
    for a studio amp i would have something small....maybe an old B15 or something......i need something to keep up with two drummers