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    Another Use For the Pas 3


    Posts : 71
    Join date : 2012-09-02
    Location : Bellingham WA

    Another Use For the Pas 3  Empty Another Use For the Pas 3

    Post by Elrick on Wed Mar 18, 2015 6:35 pm

    Last fall I picked up a free Baldwin 45 tube organ with the intention of converting it into a guitar and/or mono hi-fi amp. Until I build a proper guitar preamp w/ vibrato, I've enlisting my old PAS 3 w/ tone controls for the guitar preamp. It sounds terrific if you want clean natural sound, sans reverb, which is mostly what I like. The organ amp amp consists of a single 12AX7 and 4 parallel push pull 6L6GB with 2 5U4's for rectification. Probably good for about 45 watts into two 12" full frequency speakers.  This is what I started with:  Another Use For the Pas 3  DSC_2896_zps24a35bdf

    This is what I ended up with. I made a point in using the original wood and fasteners. Sounds great but there are a couple of low frequency rattles I have to address. With the PAS 3 I need to really back off the bass controls and max out the treble to get it to sound how I want. But it does produce a nice tone.

    Another Use For the Pas 3  DSC_3084_zpss5jbz6xs

    Another Use For the Pas 3  DSC_3080_zpsvajd0oxm

    Another Use For the Pas 3  DSC_3092_zpsjkbflx6f

    What do you think? Is this another unsung potentiality of the original PAS 3?  

    One circuitry question I do have has to do with the inputs. Currently I have the PAS 3 output going into the original amp's 50 K pot which feeds the grid of the 12AX7 in the amp. That works fine, no problem. I also have a 1/4" jack connected to the same grid of the 12AX7, I use this connection for line level inputs like from a radio headphone jack, works perfectly and I don't need the PAS 3 for doing that.  What I would like to do is use the radio and the guitar w/ the PAS 3 at the same time. That way I could play along with the radio through the amp. Problem is if the radio and the PAS 3 are connected at the same time I can only hear the radio. The guitar -PAS 3 has doesn't get through. Is this an impedance problem, or whats going on? Does my question make sense?

      Current date/time is Thu Feb 27, 2020 10:57 pm