So. USB, reasonably portable, 8 inputs.
That sort of narrows down the choice quite a bit. I am no expert on the market and there has to be about a million different ones to choose from. My personal experience is with firewire units, then there are quite a lot more to choose from. I cannot enough recommend the Fireface 800 I currently run -- getting a fireface interface for your laptop is not expensive in any way. Rambling on ...
Now, one example, never seen in real world, M-Audio Fasttrack Ultra 8R (why do they name things that funny). Quite impressive feature set and not in the esoteric price category.
http://www.m-audio.com/products/en_us/FastTrackUltra8R.htmlThere are a few things to look for in the specs. Like:
- number of channels (they generally give you max 8 inputs, any more you need one more box with digital out, Behringer ADA8000 is a perfect starting box then).
- some kind of built-in mixer functionality to create monitor mixes when needed
- headphone outputs and such
- compatibility with mac/pc and or special programs (like the ProTools M-powered software package).
The built-in effects of these boxes may look like a good idea on paper, but in real world they are not really worth that much.
The most important aspect though is never shown in manufacturers data sheets -- stability with your hardware. Some of the historical boxes never really worked. Do check up on forums and do try ask for a return policy when buying.
This might turn out to be a long search to find the perfect match.
My advice still is for you to go for a decent quality used box, if necessary adding a fireface interface to your computer. This will allow you to learn a lot on how to choose the interface of your dreams then selling your first buy with little or no loss.
// Gunnar