What is the latency (or delay) time for callbacks from the waveOutWrite API method?

Question

I\'m having a debate with some developers on another forum about accurately generating MIDI events (Note On messages and so forth). The human ear is pretty sensitive to sli

Answer 1

At the very basic level, Windows is a multi threaded OS. And it schedules threads with 100ms time slices. Which means that, if there is no CPU contention, the delay between the end of the buffer and the waveOutWrite callback could be arbitrailly short. Or, if there are other busy threads, you have to wait up to 100ms per thread. In the best case however... CPU speeds clock in at the GHz now. Which puts an absolute lower bound on how fast the callback can be called in the 0.000,000,000,1 second order of magnitude.

Unless you can figure out the maximum number of waveOutWrite callbacks you can process in a single second, which could imply the latency of each call, I think that really, the latency is going to be orders of magnitude below preception most of the time, unless there are too many busy threads, in which case its going to go horribly, horribly wrong.