Manual-1
DA 26
DISTRIBUTION AMPLIFIER
OPERATORS MANUAL
WEAR PARTS:
This product contains no wear parts.
QUICK START
Are you in a hurry? For optimum system performance, we recommend reading the detailed Operating Instructions
below and on page Manual-4. For those who can’t wait, at least be aware of these points:
• There are two inputs: Priority and Line.
• The Priority Input accepts microphone or line level.
• The Priority Input sums with an Output when assigned by the Priority Assign Port, and Priority Detect is active.
• The level of the Priority Input is unaffected by the AGC, Output Level controls or Remote Level controls.
• The AGC includes a Target Level and Ratio.
• The AGC only operates when the signal is within 26 dB of the Target Level. If the Line Input level is out of AGC range,
the 0 dB indicator on the AGC Gain Meter is off.
• With the Ratio set to infinity:1, the AGC Gain Meter should indicate about 0 dB for nominal Line Input levels.
• The AGC Fast/Slow switch only affects the gain reduction time constant. The gain increase time constant is fixed.
• Only the Line Input is processed by the AGC, Crossover, Output Level controls and Remote level controls.
• The three Crossover Outputs (full-range, high-pass and low-pass) may be selected by any of the six Outputs.
• Set the initial Output levels using the Output Level controls located on the front panel.
• Remote Level controls allow end user adjustment of Output level.
• Any combination of Remote Ports may be controlled by a single Remote device.
• Remote Level control provides automatic loudness compensation for low-pass Outputs. Loudness compensation is not
provided for full range Outputs.
• The optional VR 1 Remote Level control provides audio taper control over a range of 0 dB to –80 dB.
• Never connect anything except an approved Rane power supply to the Input that looks like a telephone jack on the rear of
the DA 26.
This is an AC Input and requires specific voltage and current. This is
not
a good place to experiment or
improvise. Use only the supply sent with your DA 26.
SETUP AND OPERATION
The outline below is detailed in the procedure that follows.
1. Set Line Input level
2. Set AGC (Automatic Gain Control) Target Level and Ratio
3. Set Crossover frequency
4. Select Source for each Output (Full-range, High-pass or
Low-pass)
5. Set Output Level controls
6. Connect Output Remote Level controls
7. Setup the Priority Input for the intended source
8. Set the Priority Input automatic Detect threshold
9. Set Ducking depth for the application
10. Priority Assign selection
1. Connect a balanced line level source to the Line Input. The
Line Input accepts an unbalanced Input connected to (+)
and (GND). We do not recommend unbalanced operation
unless the distance to the source is less than 3 feet [one
meter].
2. The Line Input signal is processed by the AGC circuit. The
AGC GAIN meter 0 dB indicator lights when the Line
Input signal is within 26 dB of the set TARGET LEVEL.
For Line Input levels more than 26 dB
below
the Target
Level, the 0 dB indicator is
off
and AGC returns to unity.
The AGC GAIN indicates the amount of attenuation used
to make the Line Input level equal the set TARGET
LEVEL. For best results, the AGC GAIN meter should
indicate about 0 dB for nominal Line Input signals.
The
best resolution for this adjustment is achieved with the
AGC RATIO set to
∞
:1.
The TARGET LEVEL is set in one of two ways:
a) If you have a source output level control, set the TAR-
GET LEVEL to the desired setting and adjust the Line
Input level so that the AGC GAIN meter indicates 0 dB
for nominal signal levels.
b) If a source output level control is not available, adjust
the TARGET LEVEL so that the AGC GAIN meter
indicates 0 dB for nominal Line Input levels. The
difference between the resulting AGC Target Level and
the desired Target Level is compensated with the
OUTPUT trims. With Input level and TARGET LEVEL
correctly set, adjust the AGC RATIO to the desired
value. We recommended values between 2:1 and
∞
:1 as
marked by the gray band. The soft-knee-response of the
AGC results in a natural sounding response with AGC
Ratios as high as
∞
:1.
continued on page Manual-4...
