[whyoh]

>I can get ~1ms latency with shared-mode WASAPI

I seriously doubt it. I don't think it's possible for shared WASAPI to go below 20-30ms. How are you measuring it? Input, output or round-trip? For easy RTL measurements, you can use this: https://oblique-audio.com/rtl-utility.php

[mkishi]

Oof, I forgot what thread I was in, because I just meant the buffer size, not the round-trip latency or not even the one-way latency to audio output. Not sure why I said "latency" as that's plain wrong, especially when we're talking from capture in this case.

It's just that I'm more focused on soft synths, and I can get a clean signal out of 64-samples buffers. Granted, that's not what I'd use with any realistic processing (for instance, I use Reaper at 128spl@48k).

While I haven't measured end-to-end yet, I do hope it stays below 20ms. I'm working on a synth-powered rhythm game, and the whole reason I chose to stick with plain WASAPI was to avoid requiring users to install extra drivers and because of Windows 10's low latency stack, with its advertised 0ms capture and 1.3ms output overhead on top of application and driver buffers.

Update: I ran RTL on the budget 2012 desktop and got worse results than I expected at 18ms@128spl for shared-mode WASAPI [1]. For some reason, I couldn't select smaller buffers. On the same hardware, exclusive-mode WASAPI managed 12.25ms@128spl, and ASIO4ALL managed 12.5ms@64spl and 15.1ms@128spl.

[1] https://i.imgur.com/xq9xiNh.png

[whyoh]

Thanks for testing. That 18ms result is actually much better than I expected for a shared mode. It got me curious, so I tried it and I was able to replicate it with my Realtek (I got 19ms). I'm still a bit skeptical about its real-world use, because I've experienced some garbled/distorted audio with some low latency modes. I also can't find that mode in Reaper, which usually has everything. Still, it looks promising.

[mkishi]

Interesting, that's very close. :)

Since I had a bunch of software open and the system had been online forever, I restarted and tested again — turns out it squeezed a couple of ms to ~16ms on shared-mode.

By the way, I believe the low latency stack is enabled system-wide, so Reaper should already be using it.

For what it's worth, on my game I've been piping a SunVox instance to a 128-samples shared-mode WASAPI stream and haven't encountered distorted audio, yet.

At the end of the day, I guess I would indeed default to recommending WASAPI unless one has hardware with great ASIO drivers.