Loopback patching for Virus performance test?

  • Over the weekend I was doing some audio interface latency benchmarks with this program called RTL Utility. To run the program you need to patch at least one interface input to an output so the program can do round-trip testing. I got it to work fine with a MOTU UltraLite-mk3, MOTU PCIe-424, and Native Instruments Komplete Audio 6, but somehow was never able to properly patch the Virus.


    I discovered the Inputs config screens, but none of my tweaks there seemed to make a difference.


    Just curious if anyone else has gotten the test to work, and if so, how you did it?


    Thanks.


    Oh, my Virus is a new TI Desktop.

  • Did you have any success at using the Virus as a regular soundcard prior to testing? Check the config menu that the parameter "input thru" is at maximum, and that the volume knob is turned up. Also, only patching out 1 to in makes sense in this scenario. There are other ways to route the input within the Virus but they probably add latency.

    Yes, I did experiment with its interface mode and I actually found it surprisingly capable in terms of its ability to withstand a high ASIO load. The latency values the driver reports at 256 samples are unusually high, though, which is why I wanted to try the benchmark to see if those numbers were accurate.


    I did adjust input thru, and that seemed to have some effect (got different error results in the test tool), but there was still something blocking the actual test. I tried both direct patching, and patching through a patch bay. When I used the latter method, where I tap the virus out signal and send it back to input, the Virus out also passed through to a FireWire interface I had, and I could see the input volume meter go up on that interface (due to feedback through the Virus's ports), so signal is definitely moving through the Virus.


    I am curious about these other routing methods you mentioned? I scoured the quick start guide and the manual, but the only information I found about the inputs was on how they can be used to modulate sounds, or a description of (only some) of the options in the Input Config screens.


    Thanks.

  • The latency values the driver reports at 256 samples are unusually high

    VC adds additional buffering to the ASIO because USB streaming is somewhat erratic. You can reduce the buffering is you run VC in "live" mode (bottom left button), but the VC will be more prone to crackle.

    I am curious about these other routing methods you mentioned?

    You can take one (at the most) of your parts and put it in input mode, which means that the input replaces the oscillators for that part (the input module is in the FX1 page of VC which might be confusing) - thus can be routed through whatever the Virus engine has to offer.