Discussion in 'Amps and Cabs [BG]' started by bassampegman, Aug 15, 2004.

  1. Can anybody who is familiar with the all tube Ampeg heads give me some help.

    The SVTCL head has an input gain control as well as a master volume.The amp has no input gain led so where to set the input gain is a bit of guess work.

    When i first got the amp i used to have the input gain on about 3/4 with the master volume at approx 4 for medium sized gigs. I play a musicman active bass, fingerstyle, and i connect it into the normal input. I have never used the -15db input on any of my amps as i play fairly lightly and my eq on the active bass is about flat so no major boost in signal.

    My eq settings on the head are, bass about 7, mid 8,mid pos control no. 4, treble about 8, the ultra low is out, ultra high is in.

    Where is the best place for the input gain, should i turn it down and turn up the master volume to work the power tubes more, or turn up the input and get the dirty Ampeg sound and turn the master volume down, or will it not really matter.
    I dont want to cook my preamp tubes by having too much input gain.

    Any help or ideas ??
  2. notanaggie

    notanaggie Guest

    Sep 30, 2003
    You won't cook any preamp tubes.

    I'd just set at what you think looks reasonable, and go. Somewhere that you have range to turn up and down as you want for both gain and master.

    If there is a problem with clipping, you'll hear it.

    That isn't a really high gain preamp, since the poweramp only needs way under a volt to drive fully (something like 0.3 volt or so).
  3. If you want it to run clean crank the master and reduce the input gain.
  4. Thanks but isnt it better to have the power tubes working harder to get the tube sound, if i turn the input gain down and the master volume up i will lose the growl i think.

    Any users out there who have used the Classic ??

    Should i crank up the input gain and not consider the pre amp tubes working harder ??

    I must admit it does sound nicer with loads of input gain and less master volume, especially for rock. It doesnt ever sound bad unlike a solid state clipping amp which is important to get the input level right.All Tube amps seem to be wanting more input gain than less ??

  5. atoni


    Jan 23, 2004
    Helsinki, Finland
    Endorsing Artist: Salo Guitars
    Use the -15db input with your active bass so you can use the input gain more effectively with active bass. I use SVT2pro and MMStingray and my input gain is somewhere between 5-7 with -15db switch in (same as using -15db input). My opinion is that It's better to give more fire to preamp tubes.
  6. The master volume is what determines the level the POWER section runs. You've got it backwards. If you want power tube grunt, you crank the master volume, but most of Ampeg's signature growl is IN the preamp, so you are correct in saying that you will most likely lose some growl if you run your master volume higher than your gain. You're not going to "cook" any of your tubes by the way you set your gains. Don't be afraid to run the amp.

    It doesn't matter. You're not "working" anything harder, you're just overloading a particular gain stage.

    Actually, almost all of the most coveted tube amps, guitar or bass, do not even have master volumes. This includes the original SVT.
  7. Im not sure that using the -15db input is correct for me, i know its the more likely place to connect an active bass. However the way i understand things is for an active bass with all its EQ boosted you would need to connect it into the -15db input so as not to have too high an input signal.Now as i only boost the treble on my Musicman and leave the Mid and Bass eq flat i feel that the input is no more than a passive bass so i connect it to the normal input and adjust the level accordingly.I think with the input gain on 5 this sounds the best balance of growl yet clear Ampeg roar

  8. if it sounds good to you, dont think so much about it -just play :)
  9. badsneakers


    May 31, 2004
    I use this head, have for 6 or so years. I have the master wide open and the gain at about 2 o'clock. Loud and dirty as ****.
  10. Yes thats about where i run the input gain, what type of bass do you use, is it active, do you use fingers or pick ?

    How often have you re-tubed the head ??

  11. Do you have a passive bass? I would think that if you plugged in a passive bass, then didn't touch any knobs and plugged in an active bass, you would notice a significant difference... I certainly do with my basses anyway.

    And yes, I'd just get it to a point where you like the sound and stop thinking about it.
  12. atoni


    Jan 23, 2004
    Helsinki, Finland
    Endorsing Artist: Salo Guitars
    You got that right, Mr. ;)
  13. badsneakers


    May 31, 2004
    I have been using my 77-78 Gibson Grabber with it set like this. My other commonly used bass is a Schecter Model T with Dimarzio pups, I have to change the settings slightly with the Schecter. Both basses are passive and I play with my fingers.
    I have never retubed the head, doesn't need it.
  14. You say you have never re-tubed it in the 6 years youve had it, how often do you use or gig it ??

    Mine is about 9 months old
  15. Good power tubes should last decades; preamp tubes should last the life of the amp. Anyone who says different is getting ready to try and sell you some tubes.
  16. Why do people suggest you should re-valve every year approx, any reason ??

  17. badsneakers


    May 31, 2004
    Could even be 7 years? I can't remember.
    I have band practice two-three times a week and play anywhere between 1-3 shows a month. This has been done consistently for the length of my ownership of the amp between two bands.

    I have never hear this so I'm guessing its like Psycho Bass Guy said, they are just trying to sell you something.

    If you like the way it sounds and all the tubes are working fine I say leave it alone. Every couple of years I bring my amp to my repair guy and have a cleaning and check up done. I have only needed one repair, it was after I dropped the head from waist height done a flight of stairs. All it needed was to have the imput jack connection fixed.
  18. A lot of people like to pretend that they know things they don't, so they'll take ANY information they find on a given subject and expound upon it as though it is fact, when in reality, they have no knowledge of the subject: musician BS. Tubes and the know-how that goes along with them got pretty scarce in the 80's and only now are experiencing a resurgence in popularity. For a long time before the internet the only source for info was Groove Tubes and Mesa Boogie ads and guitar magazine articles written by self proclaimed experts. Mesa and GT are/were in the business of selling tubes, so they published info that encouraged people to buy more tubes. After a few years, this marketing tactic became accepted as defacto truth. The real truth is, those people that ape the ads have absolutely no idea what they're talking about.
  19. The Ampeg manual states to replace the power tubes at least once a year, are they wrong, any other long term SVTCL head uses out there still using original power valves ??
  20. Yes.