What differs pro cards from consumer cards:
Pro:
- ASIO drivers for low latency (down to 2-10 ms), for Cubase, Logic and other ASIO-capable audio apps like BPM-Studio Pro, Fruityloops, Orion, Buzz, Native Instruments standalone programs, etc.
additionally perhaps EASI drivers for Emagic Logic (EASI is Emagic's answer to ASIO, but Logic can also use ASIO).
Usually you need ASIO with XP/2k to record with 24/32 bit.
Note: With XP/2k you can only use 16bit audio recording with WDM drivers, unless you have special programs. Right now, only Cakewalk Sonar and Magix/Sek'd Samplitude 6.02 can record 24 bit without ASIO.
- good ADDA converters without "cheating" (e.g. 18 bit instead of the advertised 24 bit, EQing to reduce noise).
Pro cards have good 24 bit converters or even 32 bit.
e.g. the Creative Labs Audigy can only record 16 bit and up to 48kHz, contrary to the ads.
Also you can only use 48kHz with ASIO - not good!
- good and fully compliant digital ins/outs (SPDIF or higher)
- good (driver) support
- no mic preamp because usually mics are plugged into a mixer - most consumer card mic ins have really, really bad mic pramps - avoid!
- no 3D FX - only needed for gaming, useless for audio/midi recording
- usually no wavetable onboard sounds, since its quality is too low for pro recording. Most people use external synths, samplers, or virtual synths
Example of a entry-level pro audio card:
M-Audio/Midiman Delta Audiophile 2496:
2 analog ins, 2 digital ins
2 analog outs, 2 digital outs
midi interface
driver support for ASIO (Cubase), EASI (Logic), GSIF (Gigasampler/studio)
drivers for Wiin9x, Me, 2k, XP, MacOS 9 and X, Linux
24bit, 96kHz recording
ca. 200$
www.midiman.com