difference between ampeg svp pro preamps??

Discussion in 'Amps and Cabs [BG]' started by Deano Destructo, Jan 15, 2002.

  1. Deano Destructo

    Deano Destructo Music Man/Upton addict. Hasn't slept since 1979. Supporting Member

    Dec 10, 2000
    Austin, TX
    Whats the difference between the newer svp with the 5 12ax7 and the older model with the 12au7 both sound and current wise. Also does the old one house only one tube? Why'd they switch anyway:confused: ?
  2. FalsehoodBass


    Jul 22, 2001
    Denver, CO
    actually as far as i know, the newer ones have 4 12ax7's and one 12au7... i coudn't compare for you though, sorry
  3. lo-end


    Jun 15, 2001
    Yeah, Falsehood, the current SVP-PRO has 4 12AX7s and a 12AU7 tube. Check the pdf file from www.ampeg.com

    I don't know anything about an older one with different tubes... as far as I know this is the only way the SVP-PROs were ever made. :confused:
  4. Wxp4759cb


    Nov 23, 2000
    Kansas City, MO
    I'm trying to figure out which model mine is. It looks a bit different than the brand new ones, but the controls are the same. It has 4 12ax7 AND 1 12au7. Does the 12au7 mean its the newest variety?
  5. incubus2432


    Mar 21, 2002
    Grafton, Ohio
    The only two "versions" of the SVP-Pro I'm aware of are strictly cosmetic. The newest version has a gray area around the controls and the slightly older version is all black. My understanding was everything else is the same. I'm sure there may be some minor "upgrades" but from my experience (I have owned both versions and still own the newer one) they sound and function the same.
  6. Wxp4759cb


    Nov 23, 2000
    Kansas City, MO
    I've heard they changed the tubes and DI on the newer one. Anyone know how to tell which I have?
  7. malibu

    malibu Guest

    Dec 26, 2001
    found a used SVP Pro available --
    any idea about what the approx. year would be for the change from all-black ?

    some reviews mention a (tolerable) hissing noise, any ideas about that ?
  8. malibu

    malibu Guest

    Dec 26, 2001
    MF shows a pic of the gray panel , I guess newer, version -- but states it has five 12AX7 's

    do 'ya think it is just hit or miss about which ones hiss some ?
  9. I bought a used SVP-PRO a couple months ago (the old black-faced one) - I bought a new set of tubes before I got the amp.

    When I got the amp I opened it up and found five 12AX7s. The sockets in an SVP-PRO aren't marked so I had no idea which socket got the 12AU7.

    tufnuts here hooked me up and I got the thing retubed before I got the return email from Ampeg technical support.

    Anyway, Ampeg didn't ask me for year, faceplate color or anything else - they just told me the 12AU7 went in socket #4. They didn't say (and I didn't ask) whether there were some models that were all 12AX7s.

    I think the reason for the 12AU7 is that it has a bit less gain (and therefore lower output and less noise) than a 12AX7 and is used in the "drive" stage of the preamp.

    A 12AX7 in the drive stage will probably work just fine - but if you crank it up it might overdrive later stages in the preamp. I don't think that's a problem other than the fact that it might sound like crap if you crank the drive control all the way up - but I don't know anyone who runs an SVP-PRO that way anyway.
  10. This is kind of off topic, but how much should I expect to pay for a used SVP?