Film-Tech Forum ARCHIVE: Calculate number of surrounds

This is topic Calculate number of surrounds in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by David E. Nedrow (Member # 4981) on 02-18-2016, 04:53 PM:

Given known lengths of the three non-screen walls, is there a general rule of thumb as to how many surround speakers would be needed? This would be a 7.1 auditorium.

Is it as simple as planning one for every N feet? Or should I take a look at the coverage and (overlapping as necessary) use that to guarantee coverage?

Posted by Louis Bornwasser (Member # 3063) on 02-18-2016, 08:18 PM:

None on the first 30% of each side wall. The number used behind that and across the rear wall will depend greatly on ceiling height. Low ceiling=many speakers.

Posted by Mark Gulbrandsen (Member # 72) on 02-20-2016, 10:04 AM:

There are way more parameters than that! Some other things need to be known.... Total volume of the room, individual speaker coverage, max system SPL desired, system impedance, those should allow you to calculate speaker placement both terms of height above floor, distance between speakers, mounting angle and amplifier power required to make system SPL.

Posted by Gordon McLeod (Member # 33) on 02-20-2016, 05:30 PM:

This is what we use
http://www.integralacoustics.ca/index.html

Posted by Louis Bornwasser (Member # 3063) on 02-21-2016, 10:15 AM:

All of this gets back to my objection to the R2 analyzer: what good is measuring how bad it is when no one will pay to fix it? Just makes me sad. Making it better would then be a profit-center, therefore helping to pay for the R2.