Owning both an RME HDSP9652 and a UFX, my experience is that if RME doesn't put a feature in (like USB3) it's probably for a very good reason. I bought my HDSP9652 card in 2003 or so, and it still works without a single glitch. The drivers are always current and the hardware is, well.. German. I see even the Grammies are running a full RME system for broadcasting.

USB2 and USB3 are both very fast serial buses with plenty of bandwidth for digital audio.  The problem as I understand it is that they both introduce guaranteed latency in the front and back clock buffers (circa 6ms for both).  That's a 12ms round trip latency time before you start to factor in latency created by conversion and audio driver input/output buffers. 

ston
USB2 and USB3 are both very fast serial buses with plenty of bandwidth for digital audio.  The problem as I understand it is that they both introduce guaranteed latency in the front and back clock buffers (circa 6ms for both).  That's a 12ms round trip latency time before you start to factor in latency created by conversion and audio driver input/output buffers. 

 
RME USB units achieve total round-trip latency of 4.9ms at a 48-sample ASIO buffer size/44.1k.
That's on par with the best PCIe units.

That implies that they're getting in and back out of the USB buffers in about 1.9 ms.
 
I'm genuinely interested in how they can do that, it's right on the edge of what is possible with a millisecond timer interrupt.  (Well, I guess that's how they did do it, trim the USB buffers down to the minimum possible without causing stability issues, probably the same size as the ASIO buffers you mentioned).  Pretty cool stuff :-)
 
 

That implies that they're getting in and back out of the USB buffers in about 1.9 ms.

 
Input latency of 1.7ms according to RME. That is probably why they don't want to move to other technologies such as thunderbolt.  If you have USB2 working so well for you, why change?

I need to put my interface purchasing on hold with this news. I was close to grabbing a Tascam UH-7000, but with RME's strong rep for great drivers and the announced improvements, this one might be a better long term choice.

Well, that bit of info certainly has me reconsidering the new Babyface Pro or the UCX if I can put off upgrading my 1999 Kurz K2500 for a bit longer (LOL).  Thanks!
 
Michael

musicroom
I need to put my interface purchasing on hold with this news. I was close to grabbing a Tascam UH-7000, but with RME's strong rep for great drivers and the announced improvements, this one might be a better long term choice.

You might (also) want to checkout MOTU's new Ultralite AVB.
Low round-trip latency, solid drivers, and noise-floor of -112dB.
 

Thanks Jim - will do!

Do people use the headphone outs (on the Babyface) as "normal" analog outs? (into a mixer for example?)
I'm looking for a new USB interface (for Windows) and the RME ones seem to be the best for latencies (although I'll need to look at the MOTU one that Jim recommends too)

I really only need 4x4 analog io, but a few more ins and outs never hurt ;-)

If using the headphone outs doesn't make sense, I was looking at the Fireface UC. It seems to be a good few years old now (which probably is no big deal re: sound quality) - but there still seem to be current drivers for it it.

Does anyone have any opinions about this? I've never used a RME interface before, or USB for that matter (I'm still using a Maudio Delta66) - but I'm really interested in low latency. I really "feel" the lag between hitting strings on my guitar, and the sound coming out of SONAR - when latencies are higher than 8-10ms.

Thanks.