We are looking into upgrading from a Yamaha 01r to the QU-32. The QU-32 would be more like a control surface for Sonar X3 with audio and VST instruments recorded on the PC, although most effects and EQ other than final mastering would be done on the mixer rather than Sonar.
The main concern we have is the quality of the ASIO drivers for the USB interface - I’ve never come across a USB interface that offered a low enough latency for playback and recording of multiple VST instruments, without dropouts (not acceptable when you’re in the middle of a take) or crackling. Has anyone got any reports of their experience with the ASIO drivers?
You’re not talking about recording stuff from the mixer’s input to the PC. So in your case, latency should be irrelevant.
Probably a stupid question: Why do you want to use FX and EQ from the desk? Any modern DAW (and plenty of free plugins) should provide those manipulations, right?
I’d only record dry inputs to the DAW and do anything there. Full automation, not depending on external gear, no affected by any loopback latency issue etc…
Only if you need a particular external FX which does not exist as plugin latency may be a concern (DAW->USB->DAC->ExternalFX->ADC->USB->DAW). But even if this is not correctly handled by the DAW and the ASIO-Driver (should communicate the latency with the DAW), you can still shift the re-recorded track accordingly (that’s what I did in very early days).
Probably a stupid question: Why do you want to use FX and EQ from the desk? Any modern DAW (and plenty of free plugins) should provide those manipulations, right?
Same EQ and FX parameters may sound different from one plugin/external device to the other. Maybe he likes the sound of the Qu? Or maybe he just like to work the old school way?
To be clearer in my previous answer, if he’s thinking about doing his whole mix on the Qu (the old school way with an analog mixer, a rack full of devices and no DAW), all the tracks will go through the mixer anyway so they will all end up with the same latency so no need to shift anything after doing his print. The DAW is only used as a tape recorder.
But the real question is, do you want to do the mix only or you need to record also from the board on top of previously recorded tracks? This is where latency can be a real issue.
Of course any implementation of FX/EQ will sound and behave different, but I’m not sure if switching from the 01R to the Qu is for the internal FX/EQ…
Sure, recording additional track to an existing recording could be an issue if there is some error in the latency path between ASIO and the DAW. Normally this should be properly handled in 2014 but probably worth to test…
…give me a minute…
Normally this should be properly handled in 2014 but probably worth to test…
…give me a minute…
You’re right about that. I’m expecting Allen and Heath to be on top of their game concerning that. Used to do some recording on a GS-R24M in Pro Tools 10 and !!. No issue at all. But it was running in firewire. Let me know how your test goes. I’m too lazy to setup a session right now 
…and here are the results of the quick&dirty test center:
Using Reaper on a vintage Core2 Notebook running Win7 with 2k Samples ASIO setup (something worst case scenario).
Played back a previously 32Ch session to the Qu32 and recorded back from Local Input and MixOut. Latencies are ok for normal rehearsals:
Recording dry from the input: 4mSec latency
Recording from Mix: 5mSec latency
In this case Latency is the time seen in DAW between peaks of source and re-recorded tracks.
I guess this could be reduced using a more up to date PC with smaller ASIO buffers. Not sure if Reaper has an additional latency control to play around.
From a musical standpoint this should be ok, I guess.
…and just found the additional latency control in reaper, could easily get it down to zero when configuring the values above. Of course depends if you’re recording inputs or mixes.
Lesson to learn: Qu obviously does not have internal latency compensation on different input sources. If we do live recordings all USB feeds should be set to either inputs or mixes to avoid phase problems!
Thank you for this interesting finding… 
…umm, quick&dirty testcenter forgot to check external loopback, which is the real interesting thing. So I now externally connected the Mix out into another input and recorded that one along with the digital Mix output.
Rechecked twice, but the additional latency can only be expressed in Samples: 32 (thirtytwo)
This is the same 0.7mSec stated in the Specs for XLR in to AES Digital Out…
I guess any musician or physical FX will add more latency…
latency on the back of the QU32 manual:
XLR in to XLR out 1.2ms
XLR in to AES out .7ms
Just sometimes I record what is termed or called “destructive recording”
the sound I’m actually hearing.
Getting the idea down
As an example I recorded a track from and the App “Thumbjam” from an iPad playing flute with massive delay built into the sound.
So I captured that “idea” as the client played to the music in her cans.
Sometimes in a live situation you might want to record a live show with actual sounds as though the venue was your studio.
Destructive recording again how ever you can achieve a very fast remix.
I recently spent a week running 2 complete systems (mac and PC) back to back literally.
And I really like the speed that Windows gave me or the responsiveness of windows over mac.
However I struggled a little with latency on the PC but that was a windows issue. And in this case latency was not an issue as I was not over dubbing.
Interestingly whilst on latency I installed Melodyne which recomends a massive sample rate of 1024.
However that’s using it on a mix down.
I think from my perspective just knowing about this so you can quickly change latency settings for the given scenario is the key.
Good to know one of you has a GSR24m so maybe chew the fat someday.
Love the new QU32 and lots of faders at one surface level
huge screen!
cheers
daveNZ
Thanks for all the replies. My Dad just prefers mixing and applying effects on the desk - everything is recorded dry into the DAW with the faders and panning set at zero and processed as it comes back to the desk, with the exception of the Steven Slate tape plug-in. The PC is mainly for the hundreds of VST instruments he has, if he could afford £100k of outboard gear he’d do that instead.
The key issue with the latency is playing the VST instruments. There is always going to be a slight delay between pressing a key on the keyboard to hearing the sound, and the quality of the ASIO drivers is vital for ensuring this is as low as possible, especially when running 5 or 6 heavy-duty instruments such as BFD, Slate 4, New York Pianos etc at a time.
Obviously the lower the buffer you can achieve just playing back say 32 tracks of audio (I’ve had USB interfaces before that struggled with a few tracks of audio at anything less than 1024 samples, much worse than the on-board audio with ASIO4All drivers), the lower you can get away with once you’ve added a load of VST instruments.
I can just about work with a buffer of 1024 samples, but my Dad struggles to adjust to anything larger than 512. It’s not something you can take a £2,500 gamble on. At the moment he has an RME Hammerfall ADAT interface with 24 tracks in/out which is rock solid, so anything less than that level of performance would be a disappointment for the sake of upgrading the mixer and getting more physical faders.
I guess that can only be tested along with your particular equipment, DAW and some real projects.
Playing VST “live” is always critical for latency, and a buffer of 512 bytes will automatically produce about 10mSec of it. Comparing a 24 Track audio card with the Qu32, which has to transfer 32 Channels, isn’t that fair, since your host will have to process 30% more data. Consequently there will be a 30% higher CPU load on your DAW from the additional 8 channels. If this breaks the performance, it is not the Qu…
Just did a test here. In Reason, feeding 18 tracks to the QU, USB Streaming mode set to Low Latency at 128 samples. 5ms on the input and 4 ms on the output. No dropout on playback while recording a new VST. That’s on a fairly old computer (Athlon XP 6000+, 6GB RAM)