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    PAS 2 rebuild

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    tubenutr

    Posts : 62
    Join date : 2015-01-25
    Age : 59
    Location : Northern Ontario

    PAS 2 rebuild

    Post by tubenutr on Fri Mar 11, 2016 4:50 pm

    Greetings all.

    Does anyone know where I can source PAS 3X style tone controls with centre detent. I'm trying to keep it as original as possible,
    except for changing some caps, etc.

    Thanks in advance

    peterh

    Posts : 679
    Join date : 2012-12-25
    Location : gothenburg, sweden

    Re: PAS 2 rebuild

    Post by peterh on Fri Mar 11, 2016 5:22 pm

    Eskimo wrote:Greetings all.

    Does anyone know where I can source PAS 3X style tone controls with centre detent. I'm trying to keep it as original as possible,
    except for changing some caps, etc.

    Thanks in advance

    You buy a PAS 3X :-)

    I don't think they are available elsewhere
    And they don't have a detent, it's just in the middle position they are bypassed.

    ( ask me i have 2 )

    daveshel

    Posts : 148
    Join date : 2011-11-06
    Location : Tucson AZ USA

    Re: PAS 2 rebuild

    Post by daveshel on Sat Mar 12, 2016 2:00 am

    I'm also in the process of converting a PAS2. I'm not particularly interested in ever using tone controls, but I thought if I could make them switchable it might be worth while to keep them. My thought was that even if they are the -X type, the signal is still routing through them, and if I could eliminate them entirely from the signal path, that would be preferable. But my search for switchable mods led nowhere. I'm now inclined to eliminate them from the circuit, even if I leave them in place physically.

    I'm not as concerned as you are about keeping it as original as possible, as the original power supply wasn't very good. I plan to evaluate the original audio circuits with an updated power supply in the next few weeks. My tone control decisions will come later, so please keep us apprised.

    tubenutr

    Posts : 62
    Join date : 2015-01-25
    Age : 59
    Location : Northern Ontario

    PAS 2 rebuild

    Post by tubenutr on Sun Mar 13, 2016 4:09 pm

    Thanks peterh,

    Now that I've been told what I can't do, could someone tell what I can do.

    Thanks

    tubes4hifi
    Admin

    Posts : 1292
    Join date : 2008-11-30

    Re: PAS 2 rebuild

    Post by tubes4hifi on Sun Mar 13, 2016 4:58 pm


    GP49

    Posts : 735
    Join date : 2009-04-30
    Location : East of the sun and west of the moon

    Re: PAS 2 rebuild

    Post by GP49 on Sun Mar 13, 2016 8:37 pm

    The PAS-x type controls are not conventional potentiometers.  They include contacts that function just like a tone control bypass.  In the "flat" position, the bass control shorts the two ends of the resistance track; the treble control opens the wiper so it is not connected.

    The tone control section isn't just "switched to flat," it is thus removed from the circuit.


    Last edited by GP49 on Sun Mar 20, 2016 6:31 pm; edited 1 time in total

    tubenutr

    Posts : 62
    Join date : 2015-01-25
    Age : 59
    Location : Northern Ontario

    PAS 2 rebuild

    Post by tubenutr on Sun Mar 20, 2016 5:21 pm

    Roy,

    I totally agree, I would never do what I did for my first pas.
    But, this time around I wanted to a retro build as all stock.
    I lust after one of your preamp, but spent TOO much on the pas zmod rebuild.
    Next time................

    Mike

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