[quote name='Dragonlord' post='34235' date='Jul 19 2007, 05:37 PM']How do you do that? I haven't given it much thought, but at first glance I couldn't really understand how it works.[/quote]
First you read the manual, preferably with a beverage of inspired choice such as Horlicks.
Then you either make up a cable or buy one to work with the TRS output from the receiver.If you use a standard mono cable out of the receiver you will get the 'instrument optimised output' instead of full bandwidth.
You make one which is one end TRS (tip ring sleeve, aka Stereo 1/4") and one TS (tip sleeve, aka mono 1/4"). You wire sleeve to sleeve and ring to tip. The receiver's output is TRS, and the ring signal is full bandwidth, whilst the tip signal is "instrument optimised". In X2 spiel, "insturment optimised" translates to a signal that filters off at 6 or 7 Khz or thereabouts. Not low enough to mess with a slap tone, and high enough for most people not to notice particularly if you use a cabinet without a tweeter, or if you have damaged hearing, or if your music does not need full bandwidth. Also if your amplification system of choice is not favouring full bandwidth amplification (i.e. you are distorting your signal etc) then it does not matter.
For old school tone when bass players were playing through e.g. single 15s, the natural cut off would have been about 3.5 Khz anyway, so most people who stillplay that way won't need full bandwidth. If you are on the Stanley C, Stu H, Victor W, Marcus M side of the fence, it would make a difference if you are not full bandwidth; not so if you are in the Jack B, Duck D, James J or Jaco P side of the fence.
If you don't know how to make up your cables, contact X2 or buy a standard insert cable (a Y cable, which will be one end Stereo TRS, and split into two mono 1/4 TS plugs). Just make sure you use the correct mono TS end which carries the ring signal from the stereo TRS.
I made up a few TRS to TS cables for my own use. There are comparative audio samples I posted on talkbass if you look it up. Don't ask me where, do a search.