Wattage Question

Discussion in 'Amps and Cabs [BG]' started by i_got_a_mohawk, Mar 21, 2005.

  1. Right, say a cabinet is 350watt RMS at 4ohms

    You plug a solid state head into that, that puts out 500 watts at 4ohms, you are slightly overpowering the cab

    But you plug a 300 watt all tube amp in at 4ohms, it will give a stronger output than the 500watts solid state (apparently), so would this be overpowering the cab? even tho it is rated at 50 watts under the cabs RMS?

    Or is the difference between the 2 more about signal strength (amplitude) than wattage ?

    Just a bit of a brain scratcher for these early monday mornings :)
  2. Bass Beast

    Bass Beast

    Feb 5, 2005
    From what I've gathered, the valve amp will put out 300 watts before the onset of clipping. So it won't be overpowering the cab.

    However, valve amps clip much more softly than ss so a lot of people run their valve amps slightly distorted which may push it above 350 watts, the more distorted the slightly more power you will get from it ( or so it seems)

  3. A watt is a watt. It's a unit of measurement just like an ounce, a meter or an hour. Saying a tube watt is more than a SS watt is like saying a gallon of milk is more than a gallon of water. A 500 SS watt amp puts out more power than a 300 watt tube amp regardless of what your ears tell you.
  4. Wattage does not equal signal strength, signal strength is measured in amplitude, not wattage, i was just saying wattage, because all tube amps are apparently stronger than a SS amp of similar wattage

    I was mearly asking if its the actual RMS wattage that pushes the cab over the limit, or the signal strength
  5. Joe Beets

    Joe Beets Guest

    Nov 21, 2004
    I regularly run a PLX3002 bridged (3000 watts) into a 400 watt Eden cabinet. There is never any farting no matter how hard I thump on the strings. And there is never any clipping from the speakers or from the power amp. That's what the knobs on the front of the power amp are for. This setup works perfectly for low volume gigs like backing up folk singers and it works for bigger rooms and even outdoors by simply adding more cabinets. I recommend buying the most watts you can afford and then just use the knobs on the front to adjust the amount of power going to your cabinets. Works every time. ;)
  6. Im actually moving down wattage wise, currently using the peavey firebass, and moving to an SVT II, maybe
  7. metron

    metron Fluffy does not agree

    Sep 12, 2003
    Lakewood Colorado
    a 300 watt tube amp will not necessarily put out more power then a 500 watt ss amp. both amps would be capable of blowing the 350 watt speaker. an old ampeg manual i have indicates the svt puts out 700 peak watts.

  8. Signal strength (i.e. output voltage) and wattage aren't mutually exclusive. In fact power is directly proportional to signal strength. Any amplifier that produces, say, 300W (continuous) at 4 Ohms will be able to produce an output voltage of 35 Vrms, no matter what devices it uses.

    A tube amp may sound louder than a solid state amp of equivalent rated power but the actual amount of signal it can put out is the same. The differences are in the way tube amps overdrive as compared to solid state amps and the way we perceive sound not because tube 'watts' are stronger than solid state ones.
  9. Ah right, cheers, that makes sense

    (except they are indirectly proportional, its an exponential curve not linear :p )
  10. Dr. D

    Dr. D Loaded For Bear

    Jan 13, 2005
    New Orleans, Louisiana
    The rule of thumb on poer amps is to get an amp approx. twice the power of the cabinets. and dont run it full open. The reason for this is so you dont go into your distortion realm.

    You cannot run an amp at full output into a speaker rated the same. The distortion will destroy the speaker.

    I am running 4000 watts into 2000 watts worth of speakers, and have never blown one.......so far
  11. Kael


    Dec 26, 2004
    Oklahoma City
    Somebody slap me if I am wrong here but....

    When SS amps clip bad things happen. When tube amps clip they call it color. As a result even though a tube amp may only be rated at say 300 watts RMS, it is probably capable of producing far more power only with the clip/color effect than a 300 watt RMS SS amp. Clip a SS amp and it doesn't sound so nifty. At least that's my understanding.
  12. A 300 watt tube amp is only capeable of sounding louder than a 300 watt SS amp. The human ear perceives distorted sound to be louder than clean sound at the same db level. when the SS amp clips it sounds like hell so you turn it down. When the tube amp clips everybody goes oooh and aahhh and says how much louder it is than the SS amp.
  13. ;)
    yup power's proportional to the square of the voltage so it's not directly proportional as such.... Poor choice of words on my part.... :D