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    New CCS driver board installed in my ST-120!

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    kevinmi

    Posts : 54
    Join date : 2009-11-17

    New CCS driver board installed in my ST-120!

    Post by kevinmi on Sat Dec 29, 2012 10:30 am

    I have decided to upgrade my ST-120 that I built in 2009 with the latest offerings, so I ordered up the new CCS low gain driver board and time delay module kit from Bob Latino. I ordered the cap upgrade with the board also.
    While I had the amplifier opened up, I installed the rectifier socket diode mod. I know this is probably not needed with the time delay, but with the diodes costing a whole .19 cents each, why not?
    After installation and checking voltages, I put the amp back together and installed the tubes (RCA clear top 12ua7's on the outside positions of the driver board, and A French made Radiotechnique military 12ua7 in the center position). The power tubes are Sovtec 6550's, and the rectifier tube is a vintage Mullard.
    Now here is the wierd/bizzare/ you got lucky part: After powering on the amp, I watched for the glow of the tubes, and the "clicking" of the time delay relay. Everything looked good EXCEPT no glow on the rectifier tube! I quickly shut off the amp and started pulling the tubes so I could flip it over and check out what I did wrong. As I pulled the rectifier tube, something caught my eye. I had put the tube in wrong. Apparently the locating tab on the tube was worn enough to let me plug the tube in incorrectly. How I didn't manage to blow up the amp is a mystery to me!
    So anyway, after getting everything hooked back up and glowing properly, I listened to the updated amp. Knowing that the Russian PIO caps would need a lengthy break in time, I braced myself for a less than optimum sound. Boy was I mistaken. The sound was beautiful! My amplifier never sounded so good, especially playing vinyl. I can't wait to hear the improvements after the caps settle in.
    This board was an upgrade that I didn't think would make that much difference over the original, but turned out to be well worth the money.

    Andy Jersey

    Posts : 69
    Join date : 2012-09-29

    Re: New CCS driver board installed in my ST-120!

    Post by Andy Jersey on Sat Jan 05, 2013 8:49 pm

    Having waited for th PIOs to settle in, I'd like to tell you, your amp will sound better and better for a while.

      Current date/time is Mon Sep 26, 2016 4:43 pm