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    Capacitor Upgrade Parameters VTA ST-120

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    EddieGnz1

    Posts : 23
    Join date : 2013-10-16

    Capacitor Upgrade Parameters VTA ST-120

    Post by EddieGnz1 on Thu Apr 23, 2015 5:01 am

    what are the parameters for upgrading the 4 capacitors on the top of the driver board on the VTA ST-120 ?

    it comes stock with four Nichicon 22uF at 450v.

    I am going to get the upgrade kit from Bob Latino.

    But I also want to try different capacitors. And I'm talking only about the top four caps on top of the driver board. So how high can the farad number be before something will go wrong or before I no longer benefit due to overkill? Can I get caps that are 200uF at 450v without damaging the amp in any way? what about 200uF at 630v?

    What about the voltage parameters? I understand that you don't want to be too far from the 450v number. But what about 630v? or what is the desirable range of voltage values.

    kind thanks,
    Eddie

    Bob Latino
    Admin

    Posts : 2413
    Join date : 2008-11-26
    Location : Massachusetts

    Re: Capacitor Upgrade Parameters VTA ST-120

    Post by Bob Latino on Thu Apr 23, 2015 9:09 am

    EddieGnz1 wrote:what are the parameters for upgrading the 4 capacitors on the top of the driver board on the VTA ST-120 ?

    it comes stock with four Nichicon 22uF at 450v.

    I am going to get the upgrade kit from Bob Latino.

    But I also want to try different capacitors.  And I'm talking only about the top four caps on top of the driver board.  So how high can the farad number be before something will go wrong or before I no longer benefit due to overkill?  Can I get caps that are 200uF at 450v without damaging the amp in any way?  what about 200uF at 630v?

    What about the voltage parameters?  I understand that you don't want to be too far from the 450v number.  But what about 630v?  or what is the desirable range of voltage values.

    kind thanks,
    Eddie

    Hi Eddie,

    You can go up to 100 uF on each cap (at 400 or 450 volt) BUT - from personal listening tests at higher volume levels, I do not find any difference in the sound of the amp from using 100 uF for the two center caps (C13 and C14) and 47 uF in the two side positions (C15 and C16). Going up to higher voltages and/or higher capacitances on these four caps IMHO will not make any difference in the sound of the amp.

    The capacitors you should change are the main coupling capacitors. Changing these caps out will make a noticeable difference in the sound of the amp. You did not order the Russian K40-Y upgrade main coupling caps with your amp. If you want to put in a set of four Russian K40-Y PIO in your amp, Email me directly about the costs ..

    Bob

      Current date/time is Thu Dec 08, 2016 4:03 pm