LabGruppen fP6400 User Manual

DSP 24 and DSP24B

Features

2 in 4 out speaker
processor

Controlled with

, a
proprietary software
that is included and
runs on Windows 95/
98/NT

VIEW

Pseudo FIR (Finite
Impulse Response)
filters of up to 8192
taps on each output

Up to 66 band
equalization on each
output

Crossover filters
with 0 - 96 dB/octave
slopes, any
characteristics

High resolution
magnitude and
phase compensation
of the individual
drivers is possible
with VIEW Pro

The DSP 24 is a 2 in and 4 out digital crossover and speaker
equalization unit, which offers outstanding versatility for installed or
touring sound systems.

The DSP 24 combines the function of a 2-way stereo or 3/4-way mono
active crossover unit, with a system equalization corresponding to a 66
band parametric equalizer. In addition, each output of the DSP 24 also
has independent time delay, to acoustically align the speakers and/or
drivers. Each output also has a mute switch, a digitally programmable
analog gain control and limiter threshold with front panel control knobs.

All crossover and equalization filters are performed digitally in the time
domain with a pseudo FIR filter - a combination of FIR (Finite Impulse
Response) and IIR (Infinite Impulse Response) which together emulates
an FIR filter of up to 8192 taps. Using FIR filters makes it possible to
create filters with the amplitude and the phase independent of each other,
which enables the DSP 24 user to create filters with mixed phase
characteristics. Conventional minimum phase filters can also be created,
with any curve or characteristic, with no computing latency.

The digital crossover filters in the DSP 24 can employ up to 96 dB/
octave filter slopes.

The system equalization and crossover filters in the DSP 24 are user
definable in VIEW, a proprietary software package running on a PC. It
takes the user step by step to determine all system parameters. A library
of default setups and a library of amplifier and speaker specifications are
also included, to which the user can add any amplifier or speaker.

The system equalization can be created by entering one or preferably
several speaker measurements into the PC. The software then suggests a
”best fit” equalization, with accuracy never achieved before (more
information is available in the VIEW brochure and
the ). All parameters created by the software are then
transmitted to one or several DSP 24 units via the serial communication
or memory card, and stored in a non-volatile memory. Up to 16 setups
can be stored in each DSP 24 unit. The DSP 24 can be used without the
PC and the setups can then be selected with the switches on the front
panel. The software also supports several protect functions, to prevent
unwanted changes of the parameters and front panel settings. It also
prevents copying of the filter parameters without a user password.

dba audio website

23/09/03 10:41lab.gruppen / DSP24

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Precision time
alignment of the
loudspeakers and/or
driver acoustic
centers

Programmable
limiters on each
output, with
programmable
threshold control
knobs on the front
panel

24 bit, 64 times
oversampled delta­sigma A/D and D/A
converters, with
digital anti alias and
recovery filters

48 kHz fixed
sampling rate on all
inputs/outputs

Up to 300 ms (»100
m) predelay time
available, ³170
ms(»58 m) available
in all setups

Setups are moved to
the internal memory
of the unit via a
COM port on the PC
running VIEW

The hardware is prepared for implementation of a COM-port network. It
will enable the user to view input/output levels and alter parameters of
upto 10 DSP units simultaneously in large systems.

The next release of the software package is under development. It will
simplify the control of multiple DSP units, for more information about
the software please look at the dba audio website.

There is also a version of this product available called DSP 24B, which
is identical in functionality, but it lacks thecontrols on the front panel.

© 1997-2000 Lab.Gruppen AB.

Gullregnsvägen 16 · 434 44 Kungsbacka · SWEDEN

Phone. [phone]. Fax. [phone]

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