# Four mic placement for theater calibration



## blacksound (Aug 8, 2010)

Please suggest me how can I place four mics in my theater to calibrate my system . I am planning to install cinema focux processor in my home theater to parametric eq to all my channels. Please suggest me which multiplexer is used to attach all my four mica behringer 8000. Presently I have m audio mobile pre sound card with phantom supply to interface my mic.


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## AudiocRaver (Jun 6, 2012)

Forgive me if I have misunderstood your question. It sounds like you want to multiplex or mix 4 microphones to a preamp so you can use their average measurement for equalization.

Generally speaking, multiple measurements are taken one at a time, then those measurements are averaged and the average frequency response is used to determine the needed equalization. Have you looked at Home Theater Shack's free program *Room EQ Wizard*? It has the capability of doing that, then generating filter values for equalization.


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## blacksound (Aug 8, 2010)

AudiocRaver said:


> Forgive me if I have misunderstood your question. It sounds like you want to multiplex or mix 4 microphones to a preamp so you can use their average measurement for equalization.
> 
> Generally speaking, multiple measurements are taken one at a time, then those measurements are averaged and the average frequency response is used to determine the needed equalization. Have you looked at Home Theater Shack's free program Room EQ Wizard? It has the capability of doing that, then generating filter values for equalization.


Thank you for the reply. Actually I want to average four mics and calibrate my marantz a processor. Please give me suggestion how I multiplex four inputs. Please suggest any four inputs mic pre amp which average all my inputs at one time.


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## sdurani (Oct 28, 2010)

AudiocRaver said:


> Generally speaking, multiple measurements are taken one at a time, then those measurements are averaged and the average frequency response is used to determine the needed equalization. Have you looked at Home Theater Shack's free program *Room EQ Wizard*? It has the capability of doing that, then generating filter values for equalization.


I don't think the *Focux cinema processor* the OP is talking about (assuming it is the model linked to) can save multiple measurements and average/correlate them a la Audyssey. The solution, as you mentioned, is to use REW to do spatial averaging and determine filters, and then dial that solution into the Focux parametric equalizer.


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## Wayne A. Pflughaupt (Apr 13, 2006)

blacksound said:


> Please give me suggestion how I multiplex four inputs. Please suggest any four inputs mic pre amp which average all my inputs at one time.


You don’t need anything special for the “averaging.” Any mixer with the four mic inputs you need will send combined to the outputs whatever each picks up. That said, it looks like your M-Audio Mobile Pre only has two mic inputs, so you’re going to have to get an interface with more inputs. 

Regards, 
Wayne


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## AudiocRaver (Jun 6, 2012)

Mixing together 4 mic signals is not the same as averaging 4 SPL measurements. Still not sure I see quite how the OP will accomplish EQ with the multiple mics. " Multiplex" implies switching them so they are accessed one at a time, requires some storage & processing power to follow???

Not being difficult, just trying to understand in a bit more detail.


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