RDL RUEQ3 Installation Guide

RACK-UP® SERIES

Model RU-EQ2 & RU-EQ3
Audio Tone Controls

ANYWHERE YOU NEED...

 2-Band or 3-Band Audio Equalization
 Custom Tailored Audio Bandwidth
 User-accessible Adjustments
 High-Density Rack-Mount

Convenience

 A Low-Noise, Low-Distortion

Equalizer

You Need The RU-EQ2 or RU-EQ3!

The RU-EQ2 and RU-EQ3 are part of the group of RACK-UP products from Radio Design Labs. The
RACK-UP series features the advanced circuitry for which RDL products are known, combined with
accessible user-friendly controls and displays. The ultra compact design permits high-density
installations, with three products mounted in a single rack unit. Single RACK-UPs can be mounted right
where they are needed using the adhesive method popularized by RDL’s STICK-ON® series of products.
Optional brackets permit mounting a RACK-UP module above, below, or in front of any flat surface!

APPLICATION: The RU-EQ2 and RU-EQ3 feature a balanced-bridging input, which may also be
connected unbalanced if desired. The output driver is 150  balanced, and is intended to drive

unbalanced or balanced lines of low or high impedance. Front-panel knobs provide active equalization,
each controlling a separate audio band. These bands were carefully selected to yield a module that works
effectively in a wide variety of systems. Each band’s center frequency can be either boosted or attenuated
by at least 12 dB. The RU-EQ2 has two front-panel knobs. The Q of these low and high band equalizers
was selected so that those controls can be functionally considered as a total bass-band or treble-band
control. The RU-EQ3 has a third control knob. This midrange control is optimized to voice band
adjustment, with the overlap tailored to provide smooth operation for wideband music applications.

A feature unique to the RU-EQ2 and RU-EQ3 is the OVERLOAD indication LED. When audio signals are
equalized, the boosted level can cause the output circuit to clip. Alternatively, if prominent frequencies are
attenuated, the input is likely to be turned up so that its amplifier can clip. In either event, there is a risk of
distortion. Unlike many products which show only input clipping, the RU-EQ2 and RU-EQ3’s OVERLOAD
indicator flashes if either the input or output stage clips.

The RU-EQ2 and RU-EQ3 are the optimum choice for general equalization requirements with user­adjustable knobs in both music and voice applications. Its low-noise and low-distortion performance
makes it suited to the most critical installations.

The RU-EQ2 or RU-EQ3 is the ideal choice wherever an audio equalization device is needed to provide
superior audio clarity, user adjustments, reliability, compactness and unsurpassed versatility. Use the
RU-RA3 or RC-1U rack-mount adapters to mount multiple RU-EQ2 or RU-EQ3s, or to combine related
products (such as audio mixing, video distribution, or audio metering) into a single rack unit. Used in
conjunction with other RDL modules, the RU-EQ2 or RU-EQ3 can provide the foundation for many
creative audio systems!

RDL  659 N. 6th St.  Prescott, AZ., USA 86301  [phone]  FAX [phone] www.rdlnet.com

RACK-UP® SERIES

Models RU-EQ2 & RU-EQ3
Audio Tone Controls

Installation/Operation

EN55103-1 E1-E5; EN55103-2 E1-E4

Typical Performance reflects product at publication time
exclusive of EMC data, if any, supplied with product.
Specifications are subject to change without notice.

BAL

UNBAL

AUDIO OUTPUT 24VDC POWER

24 VDC

POWER

SOURCE

SIGNAL

FROM

BALANCED

LINE-LEVEL

SOURCE

SIGNAL

FROM

UNBALANCED

LINE-LEVEL

SOURCE

TYPICAL PERFORMANCE

Input: 100 k balanced or unbalanced bridging; line-level
THD: < 0.030%; 0.010% typ. (1 kHz, +4 dBu ref.; flat response)
CMRR: > 50 dB @ 100 Hz
Frequency Response: 20 Hz to 22 kHz (EQ set flat; +/- 0.5 dB) into 600 

10 Hz to 22 kHz (EQ set flat; +/- 0.5 dB) into 10 k bridging load
Noise: < -80 dB below +4 dBu
Center frequencies:

Low Band: 80 Hz
Mid Band: 1 kHz (RU-EQ3 only)
High Band: 30 kHz

Bandwidth:

Low Band: 20 Hz to 300 Hz
Mid Band: 200 Hz to 7 kHz (RU-EQ3 only)
High Band: 3 kHz to 30 kHz

Power: 24 to 33 Vdc @ 25 mA, Ground-referenced
Mounting: Rack-mount using optional RU-RA3 triple rack mount

or RC-1U rack chassis, (single rack unit);

bottom mount using available adhesive strips; bottom or top mount to a flat

surface using optional MB-2 mounting bracket set; front mount to a panel

or backboard using optional MB-1 mounting set.
Dimensions: Height: 1.7 in. 4.3 cm

Length: 5.8 in. 15.0 cm

Depth: 2.0 in. 5.1 cm (case only)

2.5 in. 6.4 cm (including barrier block)

AUDIO OUTPUTAUDIO INPUT

SIGNAL

FEEDING

BALANCED
LINE-LEVEL
EQUIPMENT

891-3016M

Radio Design Labs Technical Support Centers

U.S.A. [phone], [phone]; Fax: [phone]

Europe [NH Amsterdam] (++31) 20-6238 983; Fax: (++31) 20-6225-287