Windows 7 WASAPI vs WDM

[breauxlg]

I am using a 424 PCIe with a 2408 MKII and 24i. I recently upgraded my PC to Windows 7 64bit and Sonar X1(I also installed 8.5 on the same box.) I cannot record using the WASAPI driver without getting all sorts of noise in the recording. I can record and playback using WDM, but am getting some dropouts. I can record in WDM and switch to WASAOI for playback, but I really just need to know the best drivers for my system. If anyone has a "How to tune Windows 7 for recording" link that they've been successful using, I'd appreciate that also.

[j_e_f]

What sort of "noise"? Does it sound like a little distortion? If so, run the MOTU console window, and make sure you don't check the box for WaveRT support for legacy programs. This actually forces all audio output to be down-sampled (very poorly, I should add) to 16-bit. It sounds horrible. Of course, if you don't check this, that means that a program which doesn't directly support WASAPI will not work with the WASAPI driver. You'll definitely need WASAPI-enabled software to use WASAPI.

Also note that the 64-bit Win7 had a bug in its support of running 32-bit WASAPI-enabled software. (It runs 64-bit WASAPI software just fine). This was fixed in a patch, so get your OS updated if you're trying to run 32-bit apps on Win7 64-bit. (But note that it is not efficient to run 32-bit apps on a 64-bit OS. You get a speed penalty. It's better to run 32-bit apps on a 32-bit OS).

Oh, and if you do get some WASAPI-enabled software, and yet it appears to very, very briefly make sound, but then quickly either make silence or repeat that brief sound over and over, check with the maker of the software. Ask if the software uses WASAPI's AUDCLNT_STREAMFLAGS_EVENTCALLBACK notification. If so, tough luck. The MOTU drivers do not support that (right now. They theoretically could in some future update). They support only polled WASAPI operation.

I discovered all this while I was developing my own custom 64-bit WASAPI-enabled audio software. The MOTU 64-bit WASAPI drivers do in fact work. But all the above must be considered in order for that to happen.

[JeffB]

What's wrong with using ASIO?

[breauxlg]

j_e_f - Thanks for the reply. The noise is a LOT of distortion. This is a sample: http://www.hishouseband.com/media/wasapi.mp3" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false; What is odd to me is that I can record using the WDM drivers, switch to WASAPI, and it plays back fine. If I record with the WASAPI drivers, it's terrible. I'm running Sonar X1 64bit. As far as I know, unless Sonar loaded some 32bit plugins, I am running all 64bit software.

JeffB - Thanks to you too for the reply. I don't know what's wrong with ASIO. I use the ASIO drivers on my Windows XP 32bit setup, but I read somewhere(now many times have we heard that) that the ASIO drivers are now "legacy" drivers on the Windows 7 64bit platform. I'm just trying to get the best performance I can out of this box. I opened a project that I had recorded on 32 bit Sonar 8.5 using the WDM drivers and had problems with dropouts. It is a 40 track project with a good bit of plugins running, but it ran just fine in XP 32Bit using ASIO drivers.

[billruys]

On paper WASAPI should be the best driver model under Windows 7, but as a long time Sonar user, believe me - ASIO is the best driver model to use with the PCIe-424 based audio interfaces.

I've been running the 64-bit version of Sonar 8.5 on Windows 7 64-bit and have tried WDM, WASAPI and ASIO. ASIO is always the most stable.

[JeffB]

Sometimes "legacy" is better than "cutting edge"!

[breauxlg]

ASIO it is. I wasn't sure if the WASAPI was stable or not yet. I usually call release 1.0 of anything "bleeding edge" instead of "cutting edge" because of the problems you almost always face. I also used the Presonus guide to tuning Windows 7 for audio and have significantly speeded up the system and reduced overhead. Thanks again for the input, folks.

There are still problems with X1 that I'm not sure I'm going to try to fight right now, but 8.5 is working pretty good so I'm in business again.

All of this came about when my old recording PC started acting flaky, freezing up, going blank, etc. I changed the power supply and it seemed to help for a while. Then I imaged all 4 of the disks to brand-new disks and that didn't seem to help much. I replaced the motherboard (all the while building and installing the new Windows 7 machine) and got the same behavior. It would work for a while and then just go away. As it turned out, it was the video card. I replaced it and now the old machine works just fine. I'm going to try to get a 24I/O for my new machine and put the 24i in the old one to have a traveling recording setup. The PC's are rack-mounted, so I'll just put it in my PA rack. I'm going to find some cheap multi-track recording software and just port across the recordings into my new studio PC for mixing, etc.

Again, thanks for the ASIO advice.

[briandeeley]

Hi

Has anyone been able to use WASAPI drivers at 24bit + 48K? I keep getting message in SOnar 8.5.1 saying incompatible format or device in use. I'ce changed Sonar + Windows device settings to be 24 + 48 and nothing else is using the Ultralite.

No big deal, ASIO is ok, but pops a bit under a load. Just wanted to see if WASAPI made any difference.

Thanks

sb