Yamaha TRB-4P owners, help me.

Discussion in 'Basses [BG]' started by tbader, Aug 11, 2005.

  1. tbader


    Jun 29, 2005
    Ok, so I bought this bass at Guitar Center a few months ago, and it absolutely sounds fantastic, like no other Yamaha I've heard. But there is absolutely a total lack of info on this particular instrument. My questions are:

    What is the wiring/knob configuration on a factory bass?
    Was there ever a model with stacked tone pots? It seems as if there's 4 frequencies on this bass: bass, mid high, mid sweep, and a very harsh treble, which I rarely even turn up.

    A technician from Yamaha gave all wiring diagrams for the 4, 5, and 6 string models, but he wasn't quite sure of anything concerning this bass, considering it doesn't have a lot of literature.

    Supposedly the factory controls are master volume, p/j blend, piezo blend, bass, treble, and a 2 way piezo low cut switch.

    From what I can gather, the controls on mine are: p volume, j volume, bass, high mid, mid sweep, and treble (all four tone controls on the two stacked pots). The former piezo blend pot doesn't have any effect, and the 2 way switch is NOT present. In fact, it is a 3 way switch, 1st position is a kill switch, and the other two positions really do not affect the tone.

    The tonal characteristics do not reflect that of a piezo system, but I can get absolutely ANY tone I wish with this particular bass. The tone is not really my concern...but I am curious to see what this bass is actually like un-modified.

    I'm not really sure if a lot of you have this bass, but if you know anything about it, or have pics, please post them. Thanks a lot!


  2. jdogric12


    Oct 23, 2008
    Alexandria, VA
    Bumping this very old thread to say I just got a Yamaha TRB-4P, after looking for some time, being a Mike Rutherford fan. Wondering if anyone can help with this request - what do all the knobs do? Thanks, J
  3. I may be wrong because it's been a while since I used one, but I think it has a master volume, Blend, Neck Tone, Bridge Tone, And Piezo volume and on off switch. But It may not have been this exact model I was using. I had one for a few weeks to try out from a friend, and looked to be this bass.
  4. jdogric12


    Oct 23, 2008
    Alexandria, VA
    Cool, thanks!