Power Supply?

Discussion in 'Amps and Cabs [BG]' started by Ty McNeely, Oct 22, 2001.

  1. Ty McNeely

    Ty McNeely

    Mar 27, 2000
    I'm just curious. During the basketball games that our jazz band plays at, we sometimes hook our amps into a power strip (surge protector), which is in turn hooked into about a 30 foot extension cord. Would this hurt my amp (Sunn 300T)? Would there be too much power lost in the extension cord, or would there still be plenty of power supplied to it?

    BTW, if it MIGHT hurt it, rest assured I've never actually plugged my 300T into it...I didn't have it yet. All I had at that time was my Fender BXR-60.
  2. JMX

    JMX Vorsprung durch Technik

    Sep 4, 2000
    Cologne, Germany
    30 feet is nothing. I don't see why this should hurt your amp. Just make sure it's not wound on a spool.

    A surge protector won't do any damage - it's there to protect your amp from power surges, that's all.
  3. Nate Dawg

    Nate Dawg

    Apr 8, 2000
    I'd be more worried about the extension cord melting.
  4. JMX

    JMX Vorsprung durch Technik

    Sep 4, 2000
    Cologne, Germany
    I've hooked a 1kW amp on such an entension cord countless times. Germany has 230V/16A, much more than what you have in the U.S., and the cables never even got noticeably warmer than before use.
  5. FalsehoodBass


    Jul 22, 2001
    Denver, CO
    JMX.. actually that can be misleading... the reason most other countries run a higher line voltage is because less power is lost to heat that way...

    the power dissipated in cable is equal to the Voltage times the Current... P=IV

    but ohm's law says that voltage is current times resistance V=IR

    so the power lost to heat in a given extension cable is IIR... or I (squared) R. Where R is the resistance in the extension cable.

    Since your amp needs less current when the voltage is doubled, increasing the voltage actually decreases the power lost to heat in the extension cable.

    plus you're talking about watts used by the amp, not watts put out, and if the Sunn is an all tube amp, (i think it is) than it probably uses much more power than a solid state amp of comparable output...

    ok moral of the story... i'm not an electrician, but i think you'd be okay, but it would depend on what else is being plugged in as well.. if its just you, and its a heavy duty extension cable, i say go for it. If other people have some high power amps as well, maybe just feel the cord after a few minutes and see if its getting warm...? personally i think you're fine but i'm not a pro..

    oh and the surge protector can't hurt., and sorry for the rant.. its late and i can't stop typing.
  6. Ty McNeely

    Ty McNeely

    Mar 27, 2000
    Yes, the 300T is all-tube.

    And actually, there is another amp (Crate all-tube head with 4x12 cab) that our guitarist plugs in to, along with a keyboard, and a 100 watt Fender Keyboard amplifier. I guess I shoulda mentioned that, huh?:p

    I know it's probably a stupid question, but like I said I'm not extremely knowledgeable about amps and electronics and such (which is why I became a moderator...desire to learn!), so I want to make sure I don't somehow damage my amp.

    Thanks for the help!
  7. You won't damage your amp. I would make sure the extention cord is at least 16 gague (orange) with a couple devices, or 14 gague (red) with more. You can use a 12 gague (yellow) cord if you have to supply a lot of power. You should never cause damage to your amp by using good, well grounded power supply cables. If anything, you'll trip a breaker or blow a fuse before ANYTHING happens to your amp. When pulling a LOT of power (entire stage audio setup) you might want to pull from ,more than one circuit depending on the wiring in the building. Improper gorounding and power fluctuations are what cause damage to amps. It might be helpful to pick up one of those inexpensive ground testers from a hardware store if you play in different locations all the time.
  8. FWIW, you'd be well advised to pick up a $6 outlet wiring checker at your local Radio Shack. This is a regularly stocked item, and may safe your life.

    It will tell you if the wiring is correct, ground missing, neutral/ground reverse wired, etc etc. If you have bad power... don't play.