Well a Mixer would work But so would a couple Multi-Channel pre-amps, Since your Budget is pretty low you are going to have to settl;y with lower end stuff...
There is an ART 8 Channel Preamp available for about $100 and they sound OK and fairly clean as long as the Gain isn"t cranked up very high which it won"t need to be as it is best to record at -12db or so and any Volume boosting can be done with the software Levels and Plugins...
You can also get a ADA8000 ($200) which is a 8 Channel Pre with ADAT in/Out with simular quality Preamps so it can rout tracks to your PC Via ADAT or you can use the converters on the EMU and go directly in that way...
Or you can get Both and have the ADA8000 connected Through ADAT and the ART connected through your EMU and have 16 Channel of Simuatinious recording and still have a couple other left over on your EMU.....
But if you do decide to go the Mixer rout then don"t get a Behringer, Pay the couple extra Bucks and get the Yahama, You will be glad you did.....
I actually would get the Preamps in your Case cuz you get more Tracks that way but it"s up to you....
Cheers
