AMPEG SVT-CL w/active pick-ups HELP

Discussion in 'Amps and Cabs [BG]' started by burlysluggers, Nov 6, 2003.

  1. burlysluggers


    Nov 6, 2003
    i'm running an ampeg svt-cl (1998) amp through an ampeg svt classic 8X10 cab.

    i'm using a 3band eq active pick up Ernie Ball music man stingray.

    i've read, and been told that when using a bass with active pick ups, that it is recommended to use the -15db input, rather than the 0db input.

    i've played around with it, and input to the 0bd jack. when i do this, i get much greater power and clarity (obviously).

    will i ruin the amp or the tubes, or anything for that matter if i use this input with the active bass, or is it manditory to use the -15db in my case?

    please help.
  2. metron

    metron Fluffy does not agree

    Sep 12, 2003
    Lakewood Colorado
    Using the normal input with your ray is fine. I have the same bass and amp with the 410 HLF speaker. The -15 input kind of sux IMO. Its meant for active basses but I never use it.
  3. burlysluggers


    Nov 6, 2003
    hey thanx. your help is appreciated.

    have you noticed that by using the 0dB, you burn preamp tubes quicker or anything like that?
  4. metron

    metron Fluffy does not agree

    Sep 12, 2003
    Lakewood Colorado
    Nope! Preamp tubes will last just about as long as the amp. The Groove Tubes that come with the amp arent the best though from what I understand. I still have them in mine but I want to get replacements. Im not sure what kind yet but hopefully I can get my hands on some NOS. Knowledgable people around here will tell you that a set of good tubes will last 10-20 years possibly. There are a bunch of people on this board that say they are uing the original tubes in their vintage amps and that they are running at about 90% output or so. The manual for the SVT CL says that the tubes should be replaced every year or two but thats just not true. The reason they say that they have to be replaced often is probably because they want to sell their tubes...

  5. burlysluggers


    Nov 6, 2003
    thanx metron. your experience has been very helpful.

    does anyone have a contrary opinion or experience?
  6. hyperlitem

    hyperlitem Guest

    Jul 25, 2001
    Indianapolis, IN
    i dont have a contrary experience but i was always told it would hurt your speakers. It wont hurt your amp to my knowledge, which is minimal, but itll wear out your speakers faster. Your putting alot more decibels through the speakers than theyre designed for. This is all going on what ive been told. If Metron does it and it works thats great and maybe hes right. As i understood it though it was an over time kinda thing, like youd be replacing your speakers sooner than normal. Theres a very good chance im wrong but they did put that padded imput there for a reason.
  7. xyllion

    xyllion Commercial User

    Jan 14, 2003
    San Jose, CA, USA
    Owner, Looperlative Audio Products
    You won't hurt anything simply by plugging into the 0 dB input. As with any amp, your speakers are damaged if you drive them beyond their capacity. In general, you will hear distortion when you do this. So, if your sound is clean, then you are fine.
  8. monkfill


    Jan 1, 2003
    Kansas City
    My understanding is, the purpose of the -15 db pad is essentially to make your gain knob more useful if your bass has a hot output. If you have a really high output bass, you might not be able to turn the gain past, say, 3 before it starts to overdrive/clip/distort. The knob becomes very sensitive to the slightest adjustment.

    By padding the input signal, maybe now you can turn up to 6 or 7 before you reach that point where overdrive starts to happen. The knob effectively becomes less "touchy," you can turn it farther without it causing such a dramatic change in volume.

    I used to run my Modulus Flea bass through the same rig. I would plug into the 0 db input and run the gain anywhere between 3 and 7, depending on if I wanted a cleaner tone or a thicker, slightly overdriven tone, and set the Master Volume to however loud I wanted it. But this Flea bass is no louder/hotter than my passive basses.

    I think its pretty much impossible to kill the 810 cabinet (rated at 800 watts) with the SVT-CL head (300 watts). Theoretically a 300 watt amp is only capable to producing 600 watts at full overdrive/clip. You're going to be blowing out windows before you damage the cabinet.
  9. nonsqtr

    nonsqtr The emperor has no clothes!

    Aug 29, 2003
    Burbank CA USA
    Agreed. Running your input hot will not damage or destroy a tube amp in any way. What'll happen is, that if your input gets "too hot", the preamp tube will start to overdrive, and you'll get a little "crunch" in your sound (a lot of people do this deliberately to get a distorted bass sound).

    In a solid state amp, clipping isn't always a good thing, and especially if the amp is poorly designed it's possible to damage something by running it too hot.

    But in a tube amp, there is no way to cause damage by overdriving the preamp (unless you plug the input into an AC wall outlet or something like that). Note that many guitar amps are specifically designed to do this, they run the input deliberately hot to get massive amounts of overdrive and distortion.

    How I use an SVT, is turn the channel volume all the way up, then dial in the volume control on the bass to "just below crunch", so I get a nice fat sound without too much distortion.

    The SVT "fridge" is specifically designed to work with that amp, so I don't think there will be any damage to the speakers even under stressful conditions. The amp is tweaked so it doesn't put out any frequencies that are too low for the speakers to handle, and the power rating of the speaker cab is way above the amp's output, so you don't have to worry about damaging the speakers.

    By the way, I use JJ's for my preamp tubes, the JJ ECC83s is the equivalent of a 12ax7. Sometimes they can be a little noisy, so you might have to go through two or three of them to find one that's nice and quiet, but boy do they sound great when you get a good one.
  10. burlysluggers


    Nov 6, 2003
    thanx a lot for everyones help. everything you have posted will be very useful as i go back to my rig and play with my settings to get the ideal sound.

    basically i think i can rest easy, knowing that i will not be doing any damage to my gear. now its just the pursuit of the perfect tone.

    thanx again.
  11. ihixulu

    ihixulu Supporting Member

    Mar 31, 2000
    getting warmer
    FWIW, Stingrays, even though they are active, don't have a particularly hot signal. G&L is one brand that comes to mind that consistently has a very high output.
  12. metron

    metron Fluffy does not agree

    Sep 12, 2003
    Lakewood Colorado
    This is a quote by myself that I wanted to correct. I was reading the SVT manual last night and it actually says the tubes should be checked about once per year. It doesnt specify expected tube life anywhere in the manual. My bad! :rolleyes: :D