please explain me the build-in-limiter of my amp

Discussion in 'Amps and Cabs [BG]' started by flea2010, Mar 27, 2004.

  1. hi there,

    I have a swr350x with a build in limiter.
    I don't understand for what it is there. my cab has 500 watts, the amp only 350.
    in the owner's manual I fount the following:

    Its [the limiters] threshold (starting point) is preset by the factory so that the user can get maximum overall apparent volume
    without unduly overdriving (or “clipping”) the power amplifier, which can eventually damage the unit’s internal
    circuitry. This can also be helpful in preventing speaker damage when running your system at high volumes.

    does that mean, that the amp can produce more volume than it is good for itself.
    can anyone please explaing that fact for a technical-greenhorn like me.

    thank you very much,
  2. Your amp head takes the tiny signal from your guitar and turns it into a much bigger signal that it sends to your speakers. The volume control on the amp adjust how sensitive the amp is to the guitar signal. When you turn your amp up all the way it becomes so sensitive (like my wife) that it will out put its full 350 watts with a really small signal from your guitar. When you turn the volume down it will take a proportionally larger signal from your guitar to output full power. If you have the volume turned up so high that the amp is outputting full power and you give it a signal that is even larger! The amp tries to follow this signal but it can't. It tries to match proportionally the signal but runs out of gas. CLIPS the signal peeks and sounds like (well you know). Running your amp like this may cause it over heat and shut own. It can also damage the tweater and or crossover in your cabinet by sending too much of the signal to these components that usually only handle a small portion of the signal. The limiter senses this condition and adjusts the volume automatically to keep the amp within its' limitations. When the signal decreases the limiter turns its self off.
  3. JOME77

    JOME77 Supporting Member

    Aug 18, 2002
    At the risk of being reproved by the more fluid speaking tech minded TB'ers, I'll try to answer your question. The rating on your cabinet (500 watts) is the max. wattage you would typically want the cabinet to see. The wattage on your amp is the wattage (RMS) it is capable of producing (under specific conditions with a specific THD). The limiter in your amp basically senses distortion and clips it prior to your speaker producing it (basically removes the peaks) so you don't hear distortion coming from your cab. The down side is your sound is somewhat more compressed and you loose control of some dynamics. However, most of todays amps do a real good of limiting without greatly affecting your sound.