Anthem Audio D2 - Manual (Page 54)

46
3. SETUP
continued …
3.15 ARC-1 ANTHEM ROOM CORRECTION
ARC-1 corrects the effects of reflective surfaces on sound quality by measuring the response of each
speaker relative to the listening area and equalizing it. ARC equalizes response without stressing the
amplifier or speakers and does not downsample the source material to process it. ARC’s filters are neither
graphic nor parametric – ARC is a sophisticated system that flattens response using its ability to create
practically any suitable function, inherently correcting phase effects created by the room.
The default correction range is up to 5 kHz. Although the limit can be changed, a higher one is not advised
since the microphone becomes directional at upper frequencies, affecting measurement accuracy.
By analyzing the bass trend common to all measured positions, ARC also detects how much gain the room
adds. Room gain shows as a bump in the bass of the target response that ARC tailors for each speaker. ARC
does not remove it because if a room’s gain is flattened, bass sounds thin – ideal speaker response
measured anechoically, which is a straight line sloping down, is not the same as ideal in-room response.
ARC senses where each speaker’s low-frequency response declines and sets high-pass filters accordingly.
Calibration is set such that average level is the same when comparing EQ “On” vs “Off”. Note that to set
levels ARC uses a midrange band that’s wider than the standard home theater setup noise, which is centered
at 1 kHz and narrow so there’s no chance its level would be reduced by a crossover.
Sample response:
My subwoofer also has equalization. Should I use it?
Since rooms, correction systems, and speaker/listener positions vary, the answer varies although it is
best to start by disabling the subwoofer’s EQ before running ARC. If the resulting calculated and target
responses resemble each other, there is usually no reason to use the sub’s EQ. If the calculated and
target curves are significantly different from each other through a wide range, enable the sub’s EQ and
run ARC again to see if it helps. If you have run ARC with the sub’s EQ enabled, ARC must be run again
once the sub’s EQ is turned off.
Measured response before EQ
Calculated response after EQ
Target response – dotted line