Originally Posted by: LegatoVibrato... My understanding is that Presence is the amount of influence you allow your EQ/Tone settings to have...or maybe "strength" would be a better term...

[font=trebuchet ms]Not directly.

The tone controls are filters that boost or cut parts of the frequency spectrum. They are part of the preamp. And their effect does not change with the volume level.

Presense is a type of feedback control that samples the output at the speaker and feeds that signal back into the preamp. Because it is frequency-dependant, it affects the tone, and because of the interaction of the output transformer with the presense circuit, the degree of effectiveness is more pronounced at higher volumes.

Rolling the presense control all the way down will usually cut the highs and upper-mids, producing 'muddy' sound. Turning it up boosts these frequencies, causing the 'icepick in the forehead' kind of sound.[/font]