Rane THX Room EQ - Manual (Page 13)

Home THX Equalization Manual Rev. 1.5
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nel splices to the Subwoofer channel by using your Left and Right Channel EQs.
Remember, if the relative levels are off, use your Home THX Controller to adjust the levels. Use
only the Left, Center, or Right EQ controls to adjust for uneven frequency response at the
Subwoofer splice point.
WARNING! If a dip remains at the Subwoofer splice point even after drastic EQ, check for
correct loudspeaker polarity. Subwoofers or LCR speakers connected out of phase can cause
a “suck-out” at the crossover point. Subwoofers offset from the LCR plane by a large distance
or multiple Subwoofers can do the same. If you are using a single Subwoofer and have a large
offset, reverse the polarity of the Subwoofer signal. If multiple and offset Subwoofers are used, you
should attempt to smooth the response by reversing the polarity of the Subwoofer furthest from the
LCR speakers, or by repositioning the offset Subwoofer.
1.11) LISTEN!
When you have completed your room equalization, play the circulating pink noise from “Wow!”
(Chapter 7). Each front channel, Left, Center, and Right, should tonally sound very similar within the
listening area. If the circulating noise sounds very different, go back and re-measure any offending
screen channel. The reference channel for any timbre comparison is the CENTER CHANNEL.
Correct EQ with Subwoofer Splice
Frequency Hz
dB
SPL
60
64
68
72
76
80
25 40 63 100 160 250 400 630 1000 1600 2500 4000 6300 10000 16000
Fig 7
Please Note: The above curve represents a typical room EQ. Since rooms vary greatly you should
not expect every equalized room RTA to look like the above illustration. A smooth curve, without
radical peaks or dips, is what is desired. With difficult rooms, acceptable tolerances can be up to ±3 dB.
Your system is now correctly equalized.