How accurate is the RT when a microphone is used?

[jarvis24]

Short answer: pretty darn accurate. On average, maybe around +/- 1-10ms. Long answer:

It depends because voice responses are not a discrete event. Voice responses start off really quiet (on the verge of silence) and become louder over a range of milliseconds. So on which millisecond does the response actually occur? That's for you to decide, and you do so by setting a sensitivity or sound amplitude criterion in the voice response setup utility on the Tools menu.

It also depend some on your hardware (see links below).

Bottom line--the best way to check the accuracy on your particular system is to look at the actual wave files in a sound editor and compare the sound waves with the RTs that are reported by DirectRT (see links below for details).

For some additional info related to voice rt accuracy:

www.empirisoft.com/support/showthread.php?t=116
www.empirisoft.com/support/showthread.php?t=408
www.empirisoft.com/support/showthread.php?t=130
www.empirisoft.com/support/showthread.php?t=598