I've been running off a 1ghz emac for awhile but it's just not cutting it anymore. It has trouble with more than a couple plugins etc. I can easily kill it running Ableton Live 3
Anyways I've been planning on upgrading to a G5. My question is, what level should I go to?
I plan on running several audio tracks and effects, and 2 - 3 soft synths, battery, Korg Legacy, ableton live etc.
Will a single CPU be good? Or should i go dual? Is the extra $500-1000 worth getting the faster cpu's? I'm on a limited budget so if I don't need the big badass computer I'd rather just save my money, and be able to pay my rent, or buy more synths.
Any suggestions?

Since your on a tight budget you really want to do everything you can first before buying a new computer.
I run Live 4 on my 733mhz just fine as well as DP4 and a couple others. you should run a cleaning program to clean up cache files and something like tech tool pro to find and fix problems with your drives.

If you do end up buying a new one you will be fine with a single prossesor

try onyx for cleaning up your system, its both free and an excellent program. also, if you havnt tried getting more RAM yet... that always gives a big performance boost (especially when your still running off of the bare minimum..). if your REALLY desperate you could always back up your important files and reformat your hard drive... it will make your computer run like its brand new again.

i was using a 400 mhz g3 with 768 megs or RAM up until last october.... although i didnt do much audio i did tons with flash and photoshop, and was able to play demanding games with decent results.

macs are amazing machines if you take care of them, im sure you can squeeze a lot more life out of your emac