d&b D12 Hardware - Manual (Page 8)

3.3. Digital signal processing
The digital signal processing provides loudspeaker specific setups that
are selected using the front panel controls. These setups include all
loudspeaker equalization and protection functions.
A 4-band parametric equalizer is incorporated in each channel to
provide optional Boost/Cut or Notch filtering. A signal delay capability
also allows delay settings of up to 340 msec. (= 100 m/328.1 ft) to be
applied independently to either channel.
A signal generator offering pink noise or sine wave program can be
selected from the front panel controls.
Each unit can be given a unique Device Name to simplify identification
and a password protected LOCK function is also incorporated to inhibit
unauthorized setup changes.
IMPORTANT! System configurations are specific to the characteristics of each
loudspeaker and affect the frequency response and maximum output
level. To ensure optimum performance and prevent damage to system
components each type of loudspeaker has to be used in conjunction
with a suitably configured D12.
The D12 digital signal processing circuits introduce a processing delay
of 0.3 msec. into the signal path. If two identical loudspeakers are
driven by different controllers the respective delays of the units used
have to be considered (D12 = 0.3 msec., E-PAC = 1.0 msec. and
A1/P1200A no delay). The D12 effectively positions its respective
loudspeaker at a distance of 24 cm (0.79 ft) in front of a loudspeaker
driven by the E-PAC and 10 cm (0.33 ft) behind a loudspeaker driven
by the A1/P1200A.
Where the two loudspeakers form an array this will lead to an increase
in comb filtering and unpredictable coverage patterns. If the distance
between the cabinets is much greater than 1 m (3 ft) this effect becomes
negligible.
Please note that all digital signal processing equipment used in the
signal path will delay the signal. For example external digital equalizers
have a typical processing delay of about 3 ms.
D12 Amplifier, Hardware manual (4.9 EN) Page 8 of 28