Four tools that you need for setting up speakers with a receiver, measuring tape, SPL meter, frequency sweep test tone CD (or a computer connected to the receiver), and excel. If you use the Radio Shack SPL meter, go download the bais offsets speadsheet that is out there on the internet which will correct the SPL's output for the frequency range of the test tone. Personally, I prefer using 1/3 octave pink noise test tones. Sit at your listening position, pull out the measuring tape and measure the distance from the speakers to your ear. If you can, physically move/adjust the speakers so that they are the same distance (again, not always possibly, but it is the preferred method). Otherwise, you need to configure the receiver to tell it either the distances of the speakers, or the delay that you need to place on all the speakers that are closer to you compared to the one farthest away from you (basically, take the distance measurements between the speaker farthest away from you and the one you are currently configuring, let say one speaker is 8 feet 5 inches away, an the other is 10 feet away, which means 19 inches difference. Now you need to figure out how long it would take sound to travel 19 inches, since sound travels at approximately 1126 feet/sec at room temperature in low humidity, it would take 0.0014 seconds for sound to travel that 19 inchs, which means you need to set that as your delay on the closer speaker (note you may also need to add an additional delay due to how long it takes your TV/projector to display the video, but that delay you would place on all the speakers evenly in addition to the delay you just calculated, and that delay can only be found by trial and error, preferably using a audio/video test which flashes the screen in sync to a beat being played on the audio, and you can then fine tune the delay on the speakers so that the audio beat you hear matches when you see the flash on the display). Once you have the distances and delay all worked out, you should work on level matching. Break out the SPL meter and preferably put it on a camera stand/mount (the Radio Shack meter can be attacked to standard camera mounts), and raise it so that it is at ear level with the measuring microphone either pointed straight at your TV or straight up, and start running the frequency sweep pink noise. Measure each speaker individually, and write down the readings of the the different frequencies (preferably into the excel spreadsheet with the offset values). Now you can get by with just using a single white noise tone and just measuring the SPL of that tone on each speaker. And with that white noise test, raise the the sound level of the quieter speaker by the difference between it and the loudest speaker. If you do the full pink noise sweep, those numbers can let you get some hard baseline results for the room response of your speakers so that you can measure the changes that any room treatments provide (like dispersion or absorption panels/traps). You can also potentially use the frequency response values to properly set equalizer settings if your receiver has that functionality, or set dynamic equalizer points as well. The rule of thumb with setting an equalizer is that you should only really try to correct downward, so if you graph the SPL response vs the frequency values, you will wind up with a wavy line, and you want to use the equalizer to pull the higher peaks downward towards the median. Do not try to correct low values that are more than a few decibels below the median, as you can not correct room null points (i.e. where a reflection or standing wave occurs due to the shape of the room and cancels a frequency range at the listening position). Those can only be corrected via physically moving the location of the speakers, listening position, or room treatments to disperse/absorb the reflection(s) used to create the standing wave/null wave.
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