If you want an interface under $500 or so, what would you buy?

How many inputs do you need?

http://www.sweetwater.com/store/detail/Scarlett2i4This is a popular one on the lower end.
 
Something like a MOTU UltraLite-mk3 Hybrid could work. It's $50 more and I can't vouch for MOTU but a lot of guys here use their stuff. It does have more than 4 outputs though.
http://www.sweetwater.com.tore/detail/UltraLite3Hy

What about the babyface pro?

TerraSin
http://www.sweetwater.com/store/detail/Scarlett2i4This is a popular one on the lower end.
 
Something like a MOTU UltraLite-mk3 Hybrid could work. It's $50 more and I can't vouch for MOTU but a lot of guys here use their stuff. It does have more than 4 outputs though.
http://www.sweetwater.com.tore/detail/UltraLite3Hy

I'll vouch for the Motu Ultralite Mk3 Hybrid. It comes with two mic/inst pre's,6 additional line-ins, 8 line-outs, midi in/out, main outs for your monitors, and 8 built-in mixers w/internal effects. Pretty much all you need for real-time tracking. It's small, portable, and will do either Firewire or USB. It can run on Bus power if attached via Firewire - no wallwart needed.
 
 

Though a bit more than you listed, the Ultralite AVB is exceptionally good at ~$650.

• 4.9ms total round-trip latency at a 64-sample ASIO buffer size 44.1k
• Average noise-floor is ~-112dB
• Extremely flexible routing/monitoring

How do you guys feel about the Digi 003?  I can get a used one for under $200.  They're still writing drivers for it.

eph221
What about the babyface pro?

RME is solid. They are my third choice in interfaces, first being Antelope Audio followed by UAD. Babyface Pro would be good but it lacks those 4 outputs you want or it would have been my first suggestion.

it is, at least in part, a personal choice thing, but since you asked...
 
I really like the Presonus converters, and the driver for the 1818VSL works really well for me. I haven't found a use for the included console really, but who know?

I just upgraded to an Apollo Twin USB. It does monitor switching, but it is limited to two inputs in it's basic form. You can add an additional 4 (@ 96 kHz) or 8 (@ 48 kHz) inputs via the TOSlink input. It's a reasonable compromise, but definitely pushes way beyond your price point.

That said - I'd put the converters in the Apollo up against many similarly priced interfaces (Apogee, RME, Audient, etc). And I think there is a noticeable difference between the Apollo and my Presonus and Frontier Design converters. I prefer the Apollo - you might not.

The advantage, for me, is access to the UAD plug-ins on the input side. Their "Unison" technology works much better than I expected, and I'd have been perfectly happy just to have certain plugs running at the input<G>!

Things to keep in mind should you wander down the UA path:
1) their plug-ins are not cheap, and they are good - this is a dangerous (for one's wallet) combination.
2) they have not yet announced their "aggregate" solution for Windows, and in fact only the Apollo Twin is officially supported at the moment, although many are running the Apollo 8 and Apollo 16 on Windows platforms. I have not seen reports of folks using multiple UAD2 devices on Windows however (Billy Buck might have info on this.)

Beyond that, well, I used my Frontier Design solution for as long as I've had a Windows machine, and it never got in my way. In fact I'm setting up a second machine with XP just to keep access to 32 extra inputs and 32 extra outputs because while I do think the UA Apollo sounds a bit clearer, there is nothing wrong with the Tango converters. And I've still got the Presonus 1818VSL connected, for those times when I really can't get by with just 2 inputs. (I'll resolve that dilemma soon with an S/Mux capable converter, but for now...

I've heard the Focusrite and I'd rate it about the same as the Presonus. The RME is better. The MOTU stuff is, I think, as good as the Focusrite, but I've never used them in the same room, so suffice it to say neither one disappointed.

There are a lot of really good interfaces out there in your price range, and at least one that is (I think) a bit better for not a whole lot more (until you start buying plug-ins<G>)! Wish there was an easy answer...

Good luck with your hunt!

eph221
I'm interested!  Will I ever be able to connect to the avb to an ethernet port and is that faster than usb?  Are the converters first class?

You'd connect the Ultralite AVB via USB2.
USB2 has plenty of bandwidth the the amount of I/O you're talking about.
ie: RME Fireface UFX is a USB2 audio interface with 30 channels of I/O at 4.3ms total round-trip latency (44.1k).
 
The MOTU AVB units can be connected to a Mac (OSX) via Ethernet port (not currently to PC).
No big loss... performance via Ethernet is similar to running Dante' (round-trip latency is ~10ms)  
 
The Converters on the AVB as the best you'll find in a unit at $650.
The noise-floor is pretty low at -112dB.  
 
World-class units have noise-floor of -117dB... or slightly lower (with the cost you'd expect).
The larger MOTU AVB units are of this caliber (1248, 8M, etc).
 
 

Drivers and support...
RME has an unbeatable track record.
MOTU is a close second.
 
UA makes nice gear...
They're relatively new to the audio interface market.

the focusrite forte is a good product.  They just came out with a beta driver that is much better.  However it didn't resolve my problems with latency.  For future reference, if you have trouble connecting the forte, just go into device manager and click on *scan for hardware change*.  This works if plug and play doesn't
 
 
 

mikedocy
Stay away from Digi 002 and Digi 003. Neither have zero latency monitoring and both have low quality preamps.

Agreed... there's a reason why you're seeing them 2nd-hand for $200.  
 
RME and MOTU both work great with ProTools... so it's not an "either or" type decision.
A rock-solid audio interface is a great investment.

What about the tascam celesonic?  It's exactly $500.  

From a fidelity standpoint, you'd do fine with a Tascam audio interface.
They're not on par with RME/MOTU/Lynx when it comes to round-trip-latency.
This may or may not be important (depending on your scenario/use).
The UH-7000 is a standout with particularly nice converters/preamps (especially given the cost).