Velleman VDL215EQ Manual

VDL215EQ GRAPHIC EQUALIZER - - DUAL 15 BAND
1. Description
The VDL215EQ is a two-channel, 15-band, 2/3 octave graphic equalizer. The device offers 5% centre frequency
accuracy and frequency control from 25Hz to 16KHz. Special features include the selectable range (6dB or 12dB),
active balanced and unbalanced input/output connectors, adjustable level control, a passive bypass switch, an
overload threshold LED and a ground-lifting switch.
2. Installation
This equalizer is designed to be mounted in a standard 19" equipment rack or in a portable case.
3. Input / Output Connections
This equalizer is equipped with two paralleled input and output connectors. The XLR and ¼" TRS connectors are
actively balanced : pin 2 or the tip is (+), pin 3 or the ring is (-) and pin 1 or the sleeve is ground. For unbalanced
operation, you will need to use pin 2 of the XLR or the tip of the ¼" TRS as Hi (+) and pin 1 of the XLR or the sleeve
of the ¼" TRS as ground.
Balanced output requires using pin 2 of the XLR or the tip of the ¼" TRS as output Hi (+) and using pin 3 of the XLR
or the ring of the ¼" TRS as Lo (-). It does not require the use of pin 1 as the signal's ground. The signal is balanced
when it reaches the output. The ground connection is solely used for protection against interfering signals.
The inputs and outputs can be paralleled by using any of the three connectors. Note : As a rule, the ¼" TRS is used.
4. Signal Levels
Signal levels from –10dBu to +4dBu are considered normal and there is a minimum tolerance of 20dB above these
levels. Do not establish any direct connections between the microphones and the equalizers. Microphones can only
be used with a preamplifier.
5. Chassis Grounding
The rear panel of this unique equalizer is equipped with a ground-lifting switch. Excessive humming or buzzing once
the system has been installed indicates a ground incompatibility between your equalizer and the other equipment in
the system. Several combinations can be attempted. Note : ALWAYS TURN OFF YOUR AMPLIFIERS BEFORE
CHANGING YOUR GROUND. Try different combinations on units equipped with ground-lifting switches or make
sure that all chassis are connected to earth ground through the mounting screws of the front panel rack.
6. Operating instructions
The equalizer is equipped with a bypass switch with a LED indicator. When the bypass switch is ON, the green LED
will also be ON and all equalizer settings will automatically be cancelled. The signal will flow through at unity gain.
Also included is a range selection switch with LED indicators : the 6dB range has a green LED, the 12dB range a
yellow one. There is also a level control potentiometer available that has a range of -∞ to +6dB. Note : In case of
excessive gain, the red peak LED will light up when the signal comes to within 3dB of the clipping level. There is no
problem if this occurs occasionally and the LED only flashes from time to time ; if the LED is lit continuously,
however, the user should readjust the level control. Below are some tips for the initial setup.
VDL215EQ 1 VELLEMAN