Where do you place your amps?

Discussion in 'Amps and Cabs [BG]' started by cvkaiser, Jan 22, 2005.

  1. cvkaiser


    Jan 20, 2005
    Hi all,

    first I would like to introduce myself because its my first post here on talkbass. My name is Christoph V. Kaiser and I´m from Germany, playing mostly with my trio-energy jazz group Jazz Pistols (http://www.jazz-pistols.de) beside other projects.

    The thing which I´m´always be concerned of is the following: Is it wise to place the amp and other stuff on top of the cabinet like we all mostly does it which I assume? Amps and in particular tube kind of stuff are sensitive electronic devices and I´m not sure if it is good to make them used for hours to extreme vibrations. For a while I used to put my case with preamp and poweramp under the cabinet to have it higher and could hear myself better. That was even worse and after a short time I had to replace a few tubes...
    Does anybody have an idea beside this ultraheavy and expensive pro-cases?
    Best regards - Christoph
  2. Luckydog

    Luckydog Supporting Member

    Dec 25, 1999
    Christoph, I think it is a good idea to avoid unnecessary vibrations of tubes and solder joints. I put a piece of 3/4 inch foam between the cab and the head for that reason. Some amps (like older SVT) have provisions for small legs with rubber feet under the head. The feet which are srewed into the bottom of the head fit into small cups on the top of the cab. You don't even see them because the cup is slightly recessed into the cab body.
  3. cvkaiser


    Jan 20, 2005
    Hi Luckydog,

    thanks for reply. Interesting concepts of the SVT-amps. I think if you are not going to end with putting the amp beside your cabinet something like your foam-thing should at least something to consider. I would like to have some more ideas or feedback on this problem.

    Thanks in advance - Christoph
  4. I typically put my amps on the floor.
  5. I've got a piece of foam rubber which I put between the head and cab. Our drummer got it for me and it's supposedly Military spec impact absorbing rubber but I expect common or garden foam rubber does the job just as well.

    I started putting it there because my amp was vibrating off the top
    of the cab, but protecting the amp is probably an added bonus.

    You've made a good point which I'm sure a lot of people hadn't thought of.
  6. DubDubs


    Aug 23, 2004
    Los Angeles
    Auralax makes a "gramma pad" it's a small amp platform with foam supports. You can use it as an isolation between the floor and your speakers or in this case an amp and the speakers.
  7. Unless your head is vibrating off the cabinet I wouldn't worry too much about it. You'll do more damage to your gear moving it from gig to gig. Anyone ever had a solder fail on the speaker itself? You can't get much closer to the vibration source than that. IMO if you have a bad solder it will go bad sooner or later no matter where you put the amp.
  8. rockstarbassist

    rockstarbassist Banned

    Apr 30, 2002
    The Woodlands, TX
    Endorsing Artist: HCAF
    I've always rackmounted my gear, and my SKB has the little rubber feet on it, but I put a piece of foam underneath my head inside the rack to even isolate it more when moving, and not just onstage. Never seen a negative or adverse affect to doing this, so why not?
  9. Don't forget to place your favorite drink on top of the head, where it will be vibrated by the speaker - shaken, not stirred.
  10. Hawkeye

    Hawkeye Canuck Amateur

    Interesting thread. This is actually something I've thought about a few times. It is well known that tubes are microphonic, (some more than others) meaning that mechanical vibration can translate to an electrical signal.

    IN the case of tubes this may mean blurring of transients, spurious frequencies that may mess with the signal's fundamental frequencies etc.

    It is also well known in audiophile circules that power supplies (transformers etc.) can also affected by mechanical vibration.

    I have some "isonode" rubber feet that worked well under my tube stereo preamp. I'm thinking about putting them under my Ampeg SVT3Pro (5 tubes in preamp) to see if it makes any difference.

    Using a material such as "sorbothane", the intent is to dampen certain frequencies and therefore mechanically decouple the component (amp in this case) resting on top of the feet from the vibrations of the structure or speaker that it's sitting on.

    Another product that is similar are the Vibrapod feet.

    The issue isn't so much that damage that will occur to the head because of being on top of a cab, but that the sound of the amp may be somewhat blurred, distorted, or impeded from being as clean and punchy as it could because of mechanical vibrations emanating from the surface of the speaker cab.

    Attached Files:

  11. +1 for the Auralex Gramma, many uses.