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    Need some help with some SCA 35 mods



    Posts : 1
    Join date : 2017-06-03
    Age : 38
    Location : Southern US

    Need some help with some SCA 35 mods

    Post by 45scratches on Sun Jun 04, 2017 12:52 pm

    I want to do some work on my SCA 35 and was hoping the forum could help me with a little info.  I found a face plate that I am interested in. The face plate I favor doesn't allow for the mono/stereo slider switch, the filter slider switch, and the slider on/off is re-seated in a 3/8in cut out for a new rotary on/off switch update.

    I found a guide that shows how to turn the tone controls on and off using a bypass modification that uses the filter switch as an on/off switch for the tone controls but I am wondering if there are any guides that show, more specifically, how to remove the tone controls from the circuit all together.  If anyone could show me a guide or explain how to remove the stereo/mono slider and filter on/off slider switches this would be most appreciated.

    I would really love to remove the input selector switch and replace it with a two way switch. I would like to be able to remove most of the clutter inside the chassis area from the switch and the multiple wires etc. I would want to keep all of the phono section RCA terminals  and relevant wires/circuitry but I only need one pair of input RCAs outside of the phono section. I prefer the spare input if that matters at all.  If I could do this mod I would try routing the wires from the RCA terminals and the phono board to the underside of the chassis leading up to the previously hoped for 2 way switch at the front face plate. The back would be pretty cleaned up too with less annoyance to me when I have a flashlight in hand trying to trouble shoot/verify signal routing etc. A rotary 2 way switch recommendation is greatly welcome and any direction on these modifications would be greatly appreciated.

    Last but not least, if anyone could tell me which capacitors in the signal path that have the most impact on sound quality I would be very appreciative. I put a pair of Mundorf caps into the c9 and c109 spots in my Pas 4 and it made a huge improvement  to the already great sound and I would be interested in doing so with the SCA 35. I've contacted the face plate seller asking for direction to a guide to remove the tone controls and they referred me to someone else that won't be able to help me until they get done with vacation. Thanks a lot.

    Posts : 1463
    Join date : 2008-11-30

    Re: Need some help with some SCA 35 mods

    Post by tubes4hifi on Thu Jun 15, 2017 7:43 pm

    the SCA35 is basically an ST35 with a different driver board that has ALOT more gain to run the tone controls.
    If you want to remove the tone controls, you can improve the performance and reduce the noise of the SCA 35 by using ST35 driver boards.
    Also, the PC11 board is only used for phono.
    If you don't have the original manual you can download it from my website.

      Current date/time is Thu Jul 19, 2018 9:17 pm