traynor bassmate... is it Bandaxall typed?

Discussion in 'Amps/Cabs Tech Corner: Amplifier, Cab & Speakers' started by axpro, May 15, 2015.

  1. axpro

    axpro Member

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    Hey guys,

    I always have trouble with Traynors tone stacks, especially the ones that aren't DRAWN like the normal fender/marshall style.

    Working on my Bassmate, have it about 80% there... I like a lot of Bass, but this is WAY too much, especially with the 15" speaker. (it sounded AWESOME with a 12.... but I want to keep it stock)

    I am planning on reducing signal caps from .1 to .022 on the first and second preamp stage. Was thinking of changing a few values in the tone stack, but looking at the schematic always throws me for a loop.

    Any ideas for mods? Mine is closest to the third schematic in this PDF. I have already switched out the filter caps, and added a 3 prong plug. Don't want to make any big changes, as I do like the tone already, just need to get the bass under control, and add a little mids. Might figure out a cut control value to take the very top end off the amp, which gets a little shrill.

    Thanks Gents!

    http://www.0rigami.com/vb/traynor_bassmate_yba2_all.pdf
     
  2. schmidlin

    schmidlin Member

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    Definitely not a Baxandall tone stack, although it is drawn like one. Sort of a bastid, at best. What comes to mind first is the fact that it has 2 gain stages prior to the volume. Not kosher in my world, and goes against the grain of any clean tone (but maybe you don't want that, who knows). I would move the volume control to R6 and go from there. (that's just me)

    Your choking back the blocking caps is a good start for taming the bass, and rolling back the high end is a piece of cake, provided we are not talking about parasitic oscillation. That tone stack is a bit of a mess, so you will have a hard time "tuning" it.

    Hope this helps.
     
  3. axpro

    axpro Member

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    Thanks Schmidlin, I was worried it was just me!

    It is drawn all cockeyed lol.


    I was really wanting to keep this amp pretty close to stock, cause with a 12ay7 in the preamp position and single coils it is AWESOME, just a little bit bassy and a little bit too much top end, unfortuantely 99% of my guitars have humbuckers which seem to make it both Boomier and the brightness seems worse...


    I'll see what the cap change does...
     
  4. axpro

    axpro Member

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    AND THAT IS ALL SHE WROTE!.....

    :D


    Switched the blocking caps to .022 orange drops, and added a .002 orange drop in series with a 68k resistor to simulate a cut control post PI. The new blocking caps keep the bass a little easier to control with the stock tone stack, and the "Cut" shaves off the icepick edge of the high frequencies, letting a little more mids shine through. I even switched back to 12ax7's for the preamp. It's a little more aggressive overall too. In the HI input, dimed out, I can get a pretty convincing classic rock sound, kinda like an 18 watt marshall. into the LO input, it cleans up a little more and isn't as crazy. Both are very touch sensetive though, roll back the volume a touch, or switch to a lower gain pickup, and it cleans right up. Very nice. Now I just need to play some signal through it this weekend to work the speaker in. :) MUCH happier. and i didn't have to go medieval on the circuit. 2 components changed from stock values and the "Cut" preset are all i changed.
     
  5. J M Fahey

    J M Fahey Member

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    Weird very crude control, it only provides for treble cut, and not a real Bass control either, no surprise it sounds muddy/boomy/bassy.
    Replace it with the excellent James (improperly called Baxandall) found in most Ampegs.
    Fat, defined, punchy, it has everything, plus:
    * has a true flat position
    * provides very smooth and symmetrical boost and cut.
    * it can easikly be built around what you already have.

    You may even leave the Linear pots , no big deal, and sound won't change much by leaving the 500k treble pot instead of the proper 1M one.

    Anything you make (even a simple Fender type control) will be miles ahead of what you have today.
     
  6. axpro

    axpro Member

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    To be honest it sounds good. I am a "set it and forget it" type player, it gets a sound i like and has enough tweakability to add a little bass or treble as needed. I've built a lot of amps over the years, and really prefer the Marshall type tone stack... but I wanted to keep this closer to stock.
     
  7. Tone_Terrific

    Tone_Terrific Member

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    Running into a woofy 15 could be a big mistake. Find a good 15 and then correct the voicing, imo.
    An Emi Legend 151 is a good one.
     
  8. axpro

    axpro Member

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    Yup, I switched that out. lol. Just was doing the voicing with a 12 because the speaker was easier to get close to the bench to work on. after hearing the issues, I made the changes i mentioned while using the new legend speaker. It just translates way too much bass, even for me (a big bass fan!) Even with a bass guitar it was pretty unusable. Tightened up a few caps, added the cut control to tame the shrillness and voila! Sounds 100% better. Now to just find the "right" overdrive pedal... Something that punches up the mids nicely but doesn't re-introduce the shrill highs... and of course, something that doesn't hum like a bugger.

    The idea is for this to be at my drummer's place for our "quiet" jam nights, when we don't go all crazy and super high gain. Would make a nice "guest amp" as well.
     
  9. Tone_Terrific

    Tone_Terrific Member

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    Check out a Bad Monkey and a Tonebone Classic.
    L&M:rolleyes::D
     

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