Dx34A
Digital Sound System
Processor
• 16 factory presets for EV speaker
systems
• Full-edit mode allows access to all
parameters and saving to 30 user
memories
• Adjustable parameters include
crossover filter characteristics, low-
and high-shelving EQ, parametric
EQ, low-cut filters, input and output
delays, polarity and output limiter
characteristics
• Lock-out feature stops unauthorized use
• Mutes on each output
• 18-bit resolution, 24-bit internal
• Electronically balanced inputs/outputs
Description
The Electro-Voice Dx34A is a multifunc-
tional digital sound system processor. Its
high degree of flexibility enables the set up
and optimization of active multiway loud-
speaker systems with variables previously
unavailable in a single-rack-space device.
The unit can be configured in two-way ste-
reo, two-way dual mono, three-way mono
with a separate full-range direct out, and
four-way mono. In the three-way configu-
ration, the low and direct outputs can be
individually set to be a sum of two input
channels, useful in some applications, e.g.,
mono subwoofers with stereo main speakers.
Functional blocks include:
1. High- and low-pass filters with Bessel,
Butterworth and Linkwitz-Riley charac-
teristics and 6-, 12-, 18- and 24-dB-per-
octave slopes.
2. Tunable low-cut filters with 6- or 12-dB-
per-octave slopes and Q variable (12-dB-
per-octave slopes only) from 0.5 to 2.0,
to provide infrasonic speaker protection
and augment or extend the low-end re-
sponse of low-frequency speaker sys-
tems. Q = 2 provides a 6-dB peak boost
that is appropriate for "step-down" op-
eration of Electro-Voice TL series vented
low-frequency systems.
3. Parametric equalizers with Q variable
from 0.4 to 20.
4. Low- and high-shelving equalizers with
6- or 12-dB-per-octave slopes.
5. Limiters on each output, with adjustable
threshold, decay rate and hold time.
6. Signal delays on the inputs (2 to 1,000
msec) and each output (0 to 10 msec).
The Dx34A block diagram is shown in Fig-
ure 3. The distribution of the functional
blocks described above is different for each
basic configuration, as shown in Figures 4
through 6.
The Dx34A addresses many different sound-
system configurations and is factory pro-
grammed for a number of Electro-Voice
speaker systems. A total of 16 user presets
is available, including:
1. DeltaMax
TM
systems (DMS series).
2. MT-2 Manifold Technology
®
systems
(three way).
3. MT-4 Manifold Technology
®
systems
(four way).
4. PI Modular Series (three way).
5. MH stadium horn systems (two way).
Parameter values for other EV components
and systems can be downloaded off the
Electro-Voice BBS at 616/695-4791 (8,N,1).
The Dx34A has two basic operating modes.
The "preset mode" allows the user to select
the factory speaker presets and gives the user
control of only the master delay and the lim-
iter parameters at each output. The "full-
edit mode" provides access to all parameters,
allowing adjustment and saving of all set-
tings. Ten user memories in each of the three
configurations (two way, three way, four
way) are available for this purpose.
Input and output metering in conjunction
with input level controls and an analog level
control on each output help to maximize the
signal-to-noise ratio of the overall system.
A/D/A conversion in the Dx34A is done by
linear 18-bit converters. The input A/D
section is a 64-times oversampled sigma-
delta converter and the output D/A is
oversampled eight times. Internal resolution
is 24 bits, using the Motorola DSP56004
processor. User memories are maintained
in RAM backed up with a lithium battery
with a life of approximately five years (the
Dx34A's alphanumeric display warns of a low
battery condition).
All inputs and outputs are electronically bal-
anced with 3-pin XLR-type connectors, and
