Help with Ampeg SVT CL

Discussion in 'Amps and Cabs [BG]' started by stickynotes, Jul 22, 2013.

  1. stickynotes


    Jun 19, 2013
    I bought a used SVT head and have a problem with low volume. It was intermittent and I was able to make it cut in out by push on the preamp board by the input jacks. Or wiggling the -15db jack. I replaced it and I resoldered a lot of points on the board but it continued to intermittently lose or gain power. Sometimes it will go for an hour before messing up. I played it yesterday for about 4 hours using the 0db/passive jack because I'm beginning to suspect that it IS only the -15db jack that is the problem. It worked fine. I'm really not sure how loud the amp is supposed to be since it has had the problem from the day I got it. Using an active bass into the 0db jack and the gain and master at around 5 or 12 o'clock it was plenty loud. The -15db jack now seems to have permanent volume loss. Any ideas. I'm thinking there must be a resistor or some circuitry on the -15db side causing the problem. Thanks for any thoughts
  2. The -15db jack is for HOT active basses. If this is an all tube CL those volume settings should have made your ears ring unless you are running just a 115 or 210 cab.
  3. JimmyM

    JimmyM Supporting Member

    Apr 11, 2005
    Apopka, FL
    Endorsing: Yamaha, Ampeg, Line 6, EMG
    Don't know what's wrong, but skip the -15db jack. All it does is cut down available volume drastically and dull the sound.
  4. stickynotes


    Jun 19, 2013
    Ya when it would jump in volume on the -15db side it was way too loud with gain and master at 12 o'clock. I just went out to look at where I was for rehearsal yesterday and it was about 4 on gain and 4.5 on the master but I was going into the 0db side with an active bass. Volume was good for an average volume trio. Also I got a crackle for a few seconds while trying out the -15db side. I'm still not sure if it's putting out normal volume or not.