Velodyne Digital DrivePLUSSeries - Manual (Page 34)

OPTIMIZATION PARAMETERS
Parametric
The following table describes the three parameters of the eight EQ filters that can be adjusted during the optimization process of the
Digital Drive PLUS subwoofer. The parametric filters can help you to achieve better room equalization. Although the Auto-EQ PLUS and Self-EQ
optimization processes automatically adjust the level of the preset parametric filters, only the Manual-EQ allows adjustment of the frequency
and bandwidth, as well as level of these filters.
The parametric filters should be adjusted after the system parameters have be set.
During the Manual-EQ process, remember that all of the preset parameters are available for adjustment. At this time, you can customize each
preset to get the appropriate character for use with differing satellites or media depending on your needs and system complexity
EQ Setting Set with Set with Set with
Self-EQ Auto-EQ PLUS Manual-EQ Description
Frequency (F) No No Yes The center frequency for the parametric filter. The parametric filters
should be placed at peaks and valleys in the frequency response during
Manual-EQ optimization. You should put a filter at the highest peak first
and adjust the filter levels before proceeding to put filters at the next
highest peak. You should put filters at the peaks before putting filters at
valleys. Remember that you are using up amplifier headroom when you
raise a dip, so it is better to lower a peak.
When manually setting the filter frequencies, avoid putting more than
one filter at one frequency. The filters can be close, but if you find that
you need to stack the filters at one frequency, you have probably placed
the subwoofer or microphone in a poor location in the room near or at a
null. To correct for this RESET the subwoofer using the remote, move
the location of the subwoofer or mic and start over with the Auto-EQ PLUS
optimization and then proceed back into Manual-EQ.
The default parametric filters are at the 1/3 octave ISO frequencies:
20 Hz, 25 Hz, 32 Hz, 40 Hz, 50 Hz, 63 Hz, 80 Hz and 100 Hz.
Level (L) Yes Yes Yes The filters can be adjusted in level between +6 dB and -13 dB.
The default level is 0 for all filters.
Bandwidth (Q) No No Yes The bandwidth determines how narrow the parametric filter is.
The narrower the filter, the higher the Q value and the faster the roll
off on each side of its center frequency. The default Q setting for the
bandwidth is 4.3 The Q can be set between 0.1 and 20. The Q or
bandwidth of the filter is usually adjusted last after correctly setting
the frequency and level. It is adjusted so that as little around the dip
or peak being corrected is affected.
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Digital Drive PLUS User’s Manual OPTIMIZATION PARAMETERS