How to measure latency

[sprinter]

I need to measure the latency of a HT 5.1 amplifier so I can sync it with some other stuff I'm doing. Is there any simple, inexpensive way to do this, even approximately?

[phofman]

Originally Posted by sprinter

I need to measure the latency of a HT 5.1 amplifier so I can sync it with some other stuff I'm doing. Is there any simple, inexpensive way to do this, even approximately?

Do you mean latency from analog or digital inputs? Latency from which point exactly?

[sprinter]

Originally Posted by phofman

Do you mean latency from analog or digital inputs? Latency from which point exactly?

This is a off-the-shelf Onkyo home theater 5.1 receiver with DSP presets, etc in it. When trying to play my guitar through it just for fun, I noticed there was quite a noticeable delay from input to output.

Now, I want to use it in conjunction with another amplifier and I will have to match this latency, probably with a variable delay from an in-line DSP/crossover device.

Without a scope, is there any way I can estimate the input-to-output delay in the Onkyo?

Thanks

[phofman]

Just my 2 cents: You could use your computer sound card stereo input. Right channel will monitor a single channel input to your AVR, left channel the corresponding speaker output, through some voltage divider (a 5kohm potentiometer should do). You put some impulse signal into the AVR (e.g. created in audacity and played by your sound card) and record the stereo response again in audacity. In the wav editor of audacity you can easily read the approximate time shift of the two input channels.

[sprinter]

Originally Posted by phofman

Just my 2 cents: You could use your computer sound card stereo input. Right channel will monitor a single channel input to your AVR, left channel the corresponding speaker output, through some voltage divider (a 5kohm potentiometer should do). You put some impulse signal into the AVR (e.g. created in audacity and played by your sound card) and record the stereo response again in audacity. In the wav editor of audacity you can easily read the approximate time shift of the two input channels.

Thanks for the clever idea. In looking for Audacity I found a great looking PC software called Visual Analyser 2011
Haven't used it yet, but it should work well for this and many other things. Freeware and looks pretty nice. I have a good USB audio I/O module on the laptop which should make it a pretty good audio analysis system. It installed fine on Win 7 64 bit.

[geraldfryjr]

Visual Analyser is an awesome program and I have been using it for over a year now.
But some times it locks up on my machine.
Just wondering if anyone has experienced this?
I am using an older 2.8ghz P4 system.
It isn't as bad as the earlier versions but it still does once in a while. jer