well, with mentioning Merzbow, I'm sure you can mention Kevin Drumm, Aube, Pita, and Jim O'Rourke...

it isnt that experpimental but if you are in a scale then kinda go off it and improvise and make it in sumfim like 3,5 timing !

you could do, but that would be 7/8. if you listen to pyramid song by radiohead and try and work out any sort of timing i would give you credit.

Id have to say my favourite experimental stuff is being done by either the Constellation or Warp record labels. However, I haven't heard some of the artists mentioned, what are John Duncan, Andrew Chalk, H.N.A.S., Mika Vainio, and Christian Fennesz like?

Fennesz basically adds noise/glitchiness/field recordings to his acoustics on guitar, sometimes creating some of the best music I've heard in years. H.N.A.S. is perhaps a darker experimental group from Germany, Christof Heeman was a big part of this group and he has his own solo material now. Andrew Chalk is basically just an avant-gardist of sorts, sound manipulator. Mika Vainio is one half of the IDM/Glitch group PanSonic, his workings tend to be from quiet pulses to noise, and sometimes quirkiness. Haven't really listened to John Duncan that much, but have heard his name floating around for years.

Fennesz sounds really good, I got my hands on some songs from soulseek (after a recommend in the essential electronic albums thread). Have it on order, but they say it`s a really lousy distribution, might take months (in fact it has).
I`m not a experimental fan, but that music sounded great! I only listen to the best from Autechre and BOC, haven`t gone any deeper in this realm.

well, i would say "Endless Summer", "Live in Japan", and "Instrument" are essentials for him.

Anyone listen to Four Tet? I'm not quite sure whether he is IDM or what, there are a lot of different styles going on in his music.

I've been really liking Chris Clark lately although I've been getting into the Warp stuff a lot more in general. I think I am going to be checking out some Plaid soon.

WARP WARP WARP.
Yes Chris Clark is an absolute master, and LFO's new album is really amazing... That label goes from strength to strength. Check out LFO's new album loz it will not dissapoint..

I'm really fond of Four Tet's Rounds