measuring audio latency?

[Ben Klein]

On 10 March 2010 10:01, Avery Pennarun <apenwarr at gmail.com> wrote:
> On Tue, Mar 9, 2010 at 9:15 AM, Dan Kegel <dank at kegel.com> wrote:
>> On Tue, Mar 9, 2010 at 2:58 AM, Roderick Colenbrander
>> <thunderbird2k at gmail.com> wrote:
>>> I might be able to measure it using my oscilloscope. Somehow I would
>>> need to play lets say the left channel 'without' latency and the other
>>> channel with and compare the two signals.
>>
>> Yes, absolutely, but it'd be good to make this measurement easy
>> to repeat by anybody interested.  To do that, let's just loop the
>> audio output back into the audio input.  The user will have to
>> provide a loopback cable (or, worst case, put his mike right up
>> to the speaker, and allow for a tiny bit of extra latency
>> from that).
>
> If sound travels at 340m/s, then a one-second sample is 340m long.  A
> 1ms delay would therefore be 340mm, or 34 cm.  Your mic would have to
> be *quite* far away from the speakers to have a significant impact on
> the delay, unless I'm missing something.

You are: air pressure ;) hehe. Yeah, I know, it won't make a
noticeable difference either; just being Devil's Advocate.

> Which is good news, I guess, since it means tests are easier.  Hope it
> goes well :)
>
> Have fun,
>
> Avery
>
>
>