Synth gadgets

Hey,

I have been surfing Craigslist for used equipment. Specifically a small effects-oriented gadget to go with my simple bread & butter keyboard.

First I saw that someone was selling a Nord Micro, which is apparently a gadget where you design patches/effects on the computer and download it into the Micro, and then attach your keyboard & get all the cool effects. (Out of production... $400.)

Then someone was selling a Yamaha RMX1 which is a 'remix sequencer' that also has effects, I suppose. (out of production, $200)

Next was a MicroKorg, also oriented toward dance grooves but I think you can set up lots of arps & effects of your own. and I assume you could also play it in conjunction with your keyboard. ($399) I think it also has audio connections as well as MIDI, plus a vocoder.

If you hook your keyboard to a unit like this, does the unit play the sounds from your keyboard or only its own sounds? (Pretty much it just has dance sounds. I wouldn't use it for pianos, dreamy pads etc.) How about the other way around, using the MicroKorg as the 'controller' and the keyboard as the sound module? Would you get your keyboard's sounds plus the MicroKorg's effects (oscillators, cutoffs, portamento).

Next I was told to check out the Alesis Micron which is a 37-key synth with very few buttons (the MicroKorg has as many buttons as an air-traffic control console.). This simple-looking unit has lots of editable parameters and cool things like a phrase arpeggio sequencer. You play something, you can loop it, etc. and play along with your loops on your regular keyboard. ($399)

Last, I saw on Craigslist someone is selling a Yamaha MO Rack mount for $500. I don't know much about MIDI, but I know that's a bargain!!

Who can tell me what a rack mount does? I know it contains & plays MIDI sounds (like your computer does). What other functions does it have and how does it work with a simple keyboard? How do you program effects?

Thanks for your help and for reading this long post.

The Keyboard Addict....haha
With all these questions all over the forums, are you sure you just don't want a better all around synthesizer? Get it all under one hood so to speak....M3, Motiff???