Contemporary Research 232-Amp+W User Manual

Product Manual

232-Amp+
232-Amp+W

RS-232 Stereo Mixer/Amplifier
Ver 1.9 February 28, 2014

Table of Contents

Overview ............................................................................................................................................. 3

Specifications ...................................................................................................................................... 4

Field Setup .......................................................................................................................................... 5

Mix/Ducking Operation ...................................................................................................................... 5

RS-232 Control Protocol ..................................................................................................................... 6

RS-232 Commands ............................................................................................................................. 7

Control Commands ................................................................................................................................... 7

Terminal Communication Commands ......................................................................................................... 8

RS-232 Command Hints and Tips .............................................................................................................. 8

Gating and Volume ................................................................................................................................... 8

Response Strings ................................................................................................................................ 9

Input 0 (Stereo) Status Response String (V0): ............................................................................................ 9

Input 1 Status Response String (V1): ......................................................................................................... 9

Input 2 Status Response String (V2): ......................................................................................................... 9

Amp Status Response String (SV): ............................................................................................................. 9

Amp Gain Response String (VG): ............................................................................................................... 9

RS-232 Cable Connections ................................................................................................................ 10

Single 232-Amp+ ....................................................................................................................................10

Tuner/232-Amp+ Daisy-Chain ..................................................................................................................10

RK1 and RK1-HD Single Unit Rack Mount ..................................................................................................11

RK3 AV Tool Rack Kit ...............................................................................................................................11

Safety Instructions ........................................................................................................................... 12

Limited Warranty and Disclaimer ..................................................................................................... 13

Contemporary Research 2 232-AMP+

232-AMP+

232-Amp+W

Overview

The Contemporary Research 232-Amp+ is a compact, programmable mixer/amplifier aimed at integration
with flat-panel displays and video projectors. The versatile amp features a stereo line-level display/projector
audio input and two mono aux inputs, and outputs stereo sound at 40 watts RMS. The aux inputs mix levels
with the stereo input, and can be set to mute or lower other inputs when active, ideal for wireless mics and
paging applications. The Class D amplifier is highly energy-efficient, using 90% of DC power for
amplification, operating with very little heat, and consuming almost no power at all when quiet.

The 232-Amp+ fastens to the top of CR’s 232- and iC-series tuners with the optional SMA Surface-Mount
Adapter, mounts to displays or projectors, or in optional rack-mount. New iC-series tuners can link to the
232-Amp+ for interactive volume control, and one 12 VDC DC supply can power both units.

The 232-AMP+W has integrated flanges for easy surface mounting

Full RS-232 control and status is available, allowing integration with custom control systems. In addition to
setting master gain and input levels, the commands can also set aux input threshold, timing, and ducking
levels. Installers can adjust performance manually in the field using onboard switches and level
potentiometer.

 Drives stereo speakers at 16 watts RMS – 32W (16W per channel) @ 8 ohms, 40W (20W per

channel) @ 4 ohms

 Mixes one stereo line input with two mono inputs, mono inputs can "duck" other inputs, with

programmable ducking on/off, threshold, timing, and mute levels

 Features programmable input levels and volume (volume affects stereo input, mono inputs are fixed)
 Offers field adjustment with onboard DIP switches and level potentiometer
 UL 2043 plenum rated
 Integrates via 2-way RS-232 with three options:

— Connect to data link on new iC-Net tuners for interactive volume control
— Control from AMX, Crestron or other custom control systems
— Daisy-chain RS-232 control with a 232-series tuner (Amp is Device 1)

 Links DC power to CR tuner to provide single 12 VDC power source for amp and CR tuner (Amp level

will be lower at 12 VDC)

 Connects speakers and control from captive screw terminals
 Mounts to top of CR tuners with optional SMA bracket, next to CR tuners in new RK-1, and RK-3 AV

Tool rack kit

 Includes 4 A DC power supply (domestic only), and captive-screw control terminals

 Options:

— SMA Surface-Mount Adapter

— PMT-1 Pole Mount Adapter for 232- and IC-series tuners
— DC-2 Y Adapter supplies DC power to tuner and amp @ 12 VDC

Firmware

 Version 1.7 – Fixes bug where a bump command did not affect Line input volume
 Version 1.5 – Improves ducking performance, Mono 1 and 2 will trigger amp on as well as Line
 Version 1.8 - Adds a Mute On/Off to inputs
 Version 1.9 – Helps to reduce noise in some applications, requires a board modifications in older

232-AMP and AMP+ units.

Contemporary Research 3 232-AMP+

Physical

232-Amp+: 5.5" [140mm] wide x 1.1” [28mm] height x 3.5” [86mm] deep

7.7” [196mm] wide with SMA bracket

232-Amp+W: 7.7” [196mm] W x 1.1” [28mm] H x 3.5” [86mm] D
Weight: 8 oz [226g]
Enclosure: All aluminum with durable black powder coat paint
232-Amp+ Mounting: Optional SMA Brackets attach 232-Amp+ to CR tuner or surface,

mount alongside CR tuner in RK-1, rack-mount in RK3 rack kit

232-Amp+W Mounting: Integrated flanges for surface mounting
Standards: RoHS compliant and energy-efficiency meets new California standards, UL

2043 plenum rated

Audio

Amplifier

Inputs

Class D, highly energy-efficient, operates with very little heat
Stereo: Stereo 3.5 mm jack, unbalanced, 7.5K ohms impedance, 1.4 V RMS max
Programmable input level
Inputs 1 and 2: Two Mono 3.5 mm jack, unbalanced, 7.5K ohms, 1.4 V RMS max
Programmable for input level and ducking gating, timing, and mute levels

Gain Potentiometer: Adjusts volume in normal mode, sets other levels in program mode
DIP switches: Located on bottom of 232-Amp+ interact with Gain for field setup
Operation: Master volume commands affects Input 1 only

Output

Speakers: 5-pin captive-screw terminal for stereo speaker installation, 8 or 4 ohm
Watts @ 18 VDC: 32W RMS (16W per channel) @ 8 ohms

40W RMS (20W per channel) @ 4 ohms
Watts @ 12 VDC: 16W RMS (8W per channel) @ 8 ohms
30W RMS (15W per channel) @ 4 ohms

Gain: Added gain 20 dB (default), programmable to 26, 32, or 36 dB
THD + Noise: 0.25% typical
Response: +/-1 dB, 20 Hz to 20 kHz, 1 watt output
Crosstalk: >65 dB @ 1 kHz, >58 dB @ 20 kHz
Protection: Thermal and short-circuit protected, auto-recovery

Control

5-pin captive-screw terminal
RS-232: GND, TX and RX
Signal (Sig): future IR input
Power (V+): 12-18 VDC output to tuner or accessory
DIP switches on bottom of 232-Amp+ interact with Gain for field setup

Power

Power LED: Green LED flashes when DC power is active, slow flash in standby mode
Power In: 5-pin captive-screw terminal

3 A maximum @ 18 VDC, 11.5 to 19 VDC, 18 VDC typical (may be unregulated)

Includes

18 VDC 3 A digital switching power supply (North American shipments only)
Two 5-pin captive screw terminals

Options

PMT-1 Pole Mount for 1RU CR tuners
SMA Surface Mount for AV Tools
RK-1 Rack Kit to mount 232-Amp+ alongside CR analog 232-series tuner
RK-3 Rack Mount Kit for mounting up to 3 AV Tools across in 19” rack, 1 RU

Specifications

Contemporary Research 4 232-AMP+