Bosso:

The "pink noise" tone on the Outlaw 950 is the same regardless of speaker setting for the mains, but the subwoofer signal changes depending on the setting of the 950's crossover.

I have output the noise tone of the Outlaw 950, the tone from the Sound & Vision Home Theater Tune Up, and wideband pink noise into my spectrum analyzer so you can see for yourself the frequency distribution of the various signals.

The Outlaw 950 internal test tone: fronts & surround


The Outlaw 950 internal test tone: subwoofer (crossover set to 60Hz)


The Outlaw 950 internal test tone: subwoofer (crossover set to 150Hz)


The Sound & Vision Home Theater Tune-Up


Wideband Pink Noise



As you can see, the tones from the Outlaw 950 and the Sound & Vision disc are heavily biased toward the mid-range frequencies, with very little information in the bass and treble regions, except for the subwoofer test (the low pass of the subwoofer test signal tracks the 950's crossover setting). The wideband pink noise has equal output across the 20Hz to 20Khz band.

You can also see that since the front and surround test tones on the 950 (and all other such pre/pros) cover only a small slice of the audio spectrum (centered at 800Hz), the relative frequency responses of your speakers in this region are very influential on the accuracy of your calibration. If for instance your mains have a hump at the frequency of the test signal, and your surrounds have a dip, the surrounds will end up being set too loud. It is for this reason that to get a really accurate calibration, the use of wideband pink noise is recommended. The "Avia" DVD test disc contains wide band pink noise 5.0 tests for this purpose. Be sure to note that these tones on the Avia disc are recorded at a -20db level rather than the more common -30db, so you need to set your sound level to 85db, rather than 75db SPL.



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The Soundhound Theater


[This message has been edited by soundhound (edited February 26, 2003).]