Soundcheck... Check 1... Check Check

The sub is in the ceiling, the parametric equalizer is linked to the receiver and plugged into the big honking amp. But- what if the sound isn't *perfect*. That's what the equalizer is for- we can balance out the frequency response of the system. It is a pain to set up. I've had three different computers up in the theater trying to simply get what is needed to start measuring the system.

Those components are:

PC with a good soundcard. I took an SB Live card out of my Linux server and put it into Aidan's PC for this test. It needs to be able to handle duplex communication without signal degredation.

A soundmeter. I'm borrowing Eric Nelson's RS Meter, which is called a sound-pressure meter. It is pretty cool because it can measure sound pressure that you can't even hear.

An equalizer. Once we analyze the sound response of the room, we then need to tune the room to flatten it out. Low frequency sounds are very susceptible to peaks and nulls because they are relatively long and can interact with furniture, room dimensions and room treatments. With the equalizer, we can tame the peaks, and modify the shape of the curve to give a desired response (that would be in the bass, Bob). Mr. Stocks was so kind as to provide me with the needed midi cables.
The Home Theater Shack has all the info you need to set up the Room Equalization Wizard (free) and the BFD (Behringer Feedback Destroyer).

Once you get the equipment, you put the meter in your seating position at ear height (the tripod will go on the sofa). You then run through a series of tests to baseline your equipment (calibrate the meter, the sound level, the sound card), and finally use sweeping sine frequencies to measure response. I'm going to test with just the subwoofer, and then add in the rest of the speakers because there is an overlap, as the main speakers have good low-frequency response.

Coming Soon... pics of the before and after frequency response. For now, let's just say that the bass is very satisfactory after the initial tuning.