sustain pedal

what exactly does this pedal do?? and what does the yngwie malmsteen foot pedal do?? any help would be great

There are two things you could be referring to; the first is a sustain pedal for a keyboard, which is basically a simple momentary on/off footswitch that activates the sustain feature in your keyboard. This is most likely not what you are referring to.

The other pedal you could be referring to is a guitar effect. Boss makes a pedal called the CS-3 (I think) Compression/Sustainer. The sustain feature of this pedal boosts the volume of the sound from your guitar as the actual signal from the pickups fades, which results in each note maintaining an even volume up until the signal drops below a certain threshold. This makes it seem like your notes are sustaining for longer than usual.

OK, someone do a better job of explaining this!

Yep the Boss CS3 is a compression sustain pedal and it does exactly what it says though often it is difficult to tell if you have it engaged or not.

The compression feature is not brilliant even standing next to a Behringer Autocom Pro.