CVA Series Owner’s Manual April 2010 www.stewartaudio.
Important Safety Instructions Before using your Stewart Audio Inc. Power Amplifier, please read this Owner’s Manual carefully to ensure optimum trouble-free performance. WARNING: TO REDUCE THE RISK OF ELECTRICAL SHOCK, DO NOT EXPOSE THIS AMPLIFIER TO RAIN OR MOISTURE. DANGEROUS HIGH VOLTAGES ARE PRESENT INSIDE THE ENCLOSURE. DO NOT OPEN THE CABINET. REFER SERVICING TO QUALIFIED PERSONNEL ONLY.
Table of Contents Important Safety Instructions······························································ 2 Table of Contents ················································································ 4 1 Welcome ························································································· 5 1.1 Features ··············································································· 5 1.
2.2.1 Universal-Mount Installation 2 Setup 2.1 Setup Precautions CAUTION: Before installing your amplifier, make sure that you have read the Important Safety Precautions at the beginning of this manual. The CVA Series also has a universal bracket available which allows the unit to be mounted against a wall or under a table. Two screws are included in the kit which will affix the bracket to the top or the side of the unit. Once this is done, two holes are available for mounting the unit where desired. 2.
2.2.3 Product Dimensions 2.4 Input Connections Your CVA Series amplifier is provided with a 3-pin Euro Block connector for its input connection. This connector will accept both balanced or unbalanced connections, however some modifications must be made for an unbalanced connection. See the next two sections for instructions on connecting your amplifier to its input source. 2.4.
2.4.2 Unbalanced Input Connections When using an unbalanced input source and connector, a jumper must be added between the negative (-) terminals and the ground terminals. Once this has been done, the unbalanced source can be connected to the positive (+) and ground terminals. Please refer to the manual of your input source in case it does not follow the standard pin-out. For your convenience, pre-wired connectors are available for purchase, see the next page for details.
2.5.1 Constant Voltage The Euro Block connector on the rear of the amplifier is capable of supplying output at either 25V or 70V depending on the step-down transformers which will be used in the speaker installation. For information on specific step-down transformer installation information, please consult the transformer’s manufacturer’s literature. 3 Operation 3.1 Operating Precautions 1. Before use, your amplifier must be configured for proper operation, including input and output wiring hookup.
3.2.1 Indicators 3.2 Controls, Indicators, and Connectors CVA Series amplifiers have three rear panel LEDs to indicate the status of the amplifier. The blue LED, labeled “ON”, will be lit when the unit is not in sleep mode. The green LED, labeled “SIG”, will light when an audio signal is present on the audio input.
3.2.3 Remote Volume Control (cont.) In order to remotely control the volume of the unit, a 10k-ohm potentiometer should be placed between the +10V pin and the GND (Ground) pin on the rear of the unit with its wiper on the RVC pin. The volume will be determined by the selected resistance on the potentiometer, the greater the resistance the louder the volume. The amplifier can be remotely muted by making a connection between the GND pin and the MUTE pin.
5 Technical Specifications Maximum Output 30Hz - 20kHz CVA-25 25W @ 25V/70V CVA-50 50W @ 25V/70V Frequency Response (+0, -3 dB) 100Hz—20kHz Power Bandwidth +/- 3dB 80Hz-30kHz THD+N <0.1% Signal-to-Noise Ratio >80dB Remote Volume Control 0-10V DC, 4-pin Block Input Sensitivity .5V (-3 dBV) Standard Voltage Gain 151X (43dB) @ 70.7V Input Impedance (Balance/Unbalanced) 20k Ohms/10k Ohms Sleep, Idle Current Draw, 1/8 Draw 0.005/0.01/0.
6.2.1 Return Authorization Number All returns to the factory for service must be accompanied by a Return Authorization (RA) number. One can be obtained by contacting Stewart Audio at (209) 588-8111 or via e-mail at support@stewartaudio.com. NOTE: Any defective products received without an RA number will be returned to sender at their expense. If Stewart Audio is unable to contact the sender in 14 days, the merchandise will be considered scrap and may be disposed of. 6.2.
7 Accessories The following accessories are available from Stewart Audio for your amplifier. All part numbers shown are Stewart Audio Part Numbers. Mounting Brackets AV-POLE Pole-mount bracket for AV Series amplifiers AV-BRACKET Universal mounting bracket for AV Series amplifiers Connection Adapters ADPT-RCA Mono Female RCA to male Euroblock. ADPT-SUMRCA Stereo Female RCA to male Euroblock. ADPT-SUM35 Stereo Female 3.
