Matrix Mix forumla

[smokenburn]

I'm looking for a thread with the distance/time ratio for mixing a matrix recording.   What is the formula, or link to the thread?

Thanks!

[smokenburn]

Time = Distance/Speed of sound (1,126 ft/s)

[Gutbucket]

Or, with respect to our purposes, it takes 1.1 milliseconds (0.0011 seconds) for sound to travel 1 foot.

[smokenburn]

sample:

4 ch matrix mix: stereo pair is located 30 ft. f/ the PA and SBD mix.

30 (distance)/1126 (speed of sound) = 26 ms (time)

add 26 ms sample delay to the sbd mix.

[goodcooker]

sample:

4 ch matrix mix: stereo pair is located 30 ft. f/ the PA and SBD mix.

30 (distance)/1126 (speed of sound) = 26 ms (time)

add 26 ms sample delay to the sbd mix.

This is accurate. Use your ears to fine tune a few ms either way. I use the sound of the bass to find the sweet spot where there is no comb filtering.

[danlynch]

This is the general rule.  Some PA systems incorporate delay.  Always check the difference by comparing the precise location of a identifiable point (drum clicks are good).

[morst]

I'm looking for a thread with the distance/time ratio for mixing a matrix recording.   What is the formula, or link to the thread?

Thanks!

If you have a mac machine, try this widget, called Sound Reference:
https://www.apple.com/downloads/dashboard/calculate_convert/soundreference.html

It lets you calculate wavelength or time based on your choice of ambient temperature. That and a calculator (widget!) to figure how much 1/48,000 of a meter comes out to, and you can nail stuff pretty well!!!

This is the general rule.  Some PA systems incorporate delay. Always check the difference by comparing the precise location of a identifiable point (drum clicks are good).

Break music over the PA can be very helpful as well. If you have it on a clean SBD feed, then call a spot in it ZERO, and then align your audience mic sources to it...