CERWIN VEGA VCU81 (01) PDF Document

The CERWIN VEGA VCU81 amplifier includes the following features:

• Full Range Class D IR Chipset

• DirectFET Power Mosfet Output Stage

• SMD Technology on 4 layer Glass PC Board

• Conformal Coated PCB assembly for added water resistance

• ICAD circuit provides superior overload protection

• Frequency response 10 Hz – 30kHz (Mono Block 10 Hz – 350Hz)

• Variable 12db crossovers

• Cerwin Vega Bass boost +12DB @45HZ

• Premium 8 gauge power connections (4 gauge recommended for mono block)

• Mono channel

• Remote Bass Knob (Included with MICRO81U/MICRO82U)

	VCU81
	600W RMS
RMS Power (1Ω)	600W X 1
RMS Power (2Ω)	400W X 1
Bridged (mono 1Ω)	600W
Bridged (mono 2Ω)	400W
Bridged (mono 4Ω)	240W

Please follow these general precautions when installing your CERWIN VEGA VCU81:

• The unit is designed for negative ground 12V DC operation only.

• Avoid installing the unit where it would be subject to high temperatures (from direct sunlight or hot air), rain, moisture, dust, or dirt.

• Do not cover the unit with carpet or wires.

• Do not use the unit with a weak auto battery. Optimum performance depends on optimum battery supply voltage.

• For safety, keep your car audio system volume moderate while driving so you can hear normal traffic sounds.

• There is no speaker level input connector. You can cut RCA’s and solder the wires to connect directly through the low-level input (RCA) or purchase an optional RCA Adaptor cable (model – CHHILVL) for a cleaner installation.

Although the CERWIN VEGA VCU81 incorporates heat sinks and protection circuits, mounting it in a tight space without air movement can damage internal circuitry. Choose a location that provides adequate ventilation around the amplifier. For easy setup, mount it so the side panel controls are accessible after installation. To increase thermal run times on low impedance loads, an additional fan is recommended. Observe the following precautions:

1. Using a felt pen, mark the mounting hole locations.

2. Mounting the amplifier on carpet will significantly reduce air flow, resulting in reduced thermal run times.

3. Mount the amplifier on a solid surface. Avoid mounting to sub woofer enclosures or areas prone to vibration. Do not install on plastic or other combustible materials.

4. Before mounting, make sure not to cut or drill into the fuel tank, fuel lines, brake lines (under chassis), or electrical wiring.

1. Before installation, make sure the source unit power switch is in the OFF position.

2. Disconnect the negative (-) lead of the battery before making any power connections.

3. When making connections, be sure that each one is clean and secure. Insulate all of your connections to prevent damage to your equipment.

4. A secure, clean ground connection is critical for your amplifier’s performance. Connect the ground directly to the car chassis to minimize resistance and avoid noise problems.

5. Add an external fuse on the amplifier’s positive (+) power lead and connect it as close as possible to the vehicle’s (+) battery terminal. Use a fuse with a rating that equals the total current consumption at full output of all amplifiers in the system. This fuse will protect the vehicle from short circuits that can cause a fire.

The Status LEDs on your CERWIN VEGA VCU81 indicate the amplifier’s operational state. They show when the amplifier is powered up normally and when there is a protection fault. The Protect LED will illuminate if there is a problem with your amplifier.

The Sensitivity control matches the preamp stage of the CERWIN VEGA VCU81 to your source unit. It is NOT a volume control. The adjustment range is between approximately 200mV to 10V. It can also handle speaker level inputs of less than 25 watts RMS.

To set the gain:

1. Turn the amplifier gains all the way down (counterclockwise).

2. If using a remote level control, plug it in and turn it to about “HALF-WAY” (12 o’clock position).

3. Turn the source unit volume up to almost full (usually about 2/3rds of the way up) or until the output starts to distort on an oscilloscope.

4. Increase the amplifier gain setting until you achieve adequate volume or until distortion becomes audible. Then, turn it down a bit until the distortion is no longer audible.

NOTE: Ideal signal-to-noise and dynamic range are achieved with the gain at minimum. Most users find adequate gain and volume at less than halfway in the adjustment range. Avoid setting the gain very high, as this will significantly increase noise and distortion.

LP/FULL/HP Crossover Adjustment: The CERWIN VEGA VCU81 is a mono block amplifier dedicated for Low Pass (LP) operation. This adjustment allows you to filter out high frequencies, sending only low frequencies to your subwoofer. The range of adjustment is between 40-400 Hz.

Vega Bass Boost: This control adds 0 to +12dB of boost at 45Hz. Be cautious when adding boost, as some subwoofer systems may not be able to handle the additional low-frequency boost. In the 0dB position, no bass boost is added.

Sub-Sonic Adjustment: This control is ONLY on the VCU81 and allows you to remove unwanted sub-sonic frequencies below the tuning frequency of a ported enclosure. This helps protect the woofer from over-excursion.

Power Input Connections: These connections are for input power (+12V), chassis ground (GND), and remote turn-on (REM). Use a minimum of 8 gauge wiring for power and ground connections; 4 Gauge is recommended for the mono block. Ensure any wiring that passes through metal has a grommet to protect it.

Speaker Output Harness: Connect your speakers to these terminals. The VCU81 mono block is stable into a 1 Ohm mono load.

The CERWIN VEGA VCU81 has a port for the included remote level control. This control allows the user to adjust the level of gain up to the maximum adjustment level set on the amplifier’s control panel. It does not add any additional boost; it only attenuates the setting that is fixed on the amplifier.

1. Plan Wire Routing: Keep RCA cables close together but isolated from the amplifier’s power cables and other high-power auto accessories to prevent noise. Use grommets when feeding wires through the firewall or any metal barrier.

2. Prepare Power Wire: Strip 5/8 inch (15.9mm) of insulation from the end of the power wire. Insert the bare wire into the B+ terminal and tighten the set screw. The B+ cable MUST be fused 18 inches or less from the vehicle’s positive battery post. Use a waterproof fuse holder.

3. Install Fuse Holder: Trim the power cable within 18 inches (45.7mm) of the positive battery post and splice in an in-line fuse holder. Do NOT install the fuse yet.

4. Connect to Battery: Strip 1/2 inch (12.7mm) from the battery end of the power cable. Crimp and solder a large ring terminal to the cable and connect it to the positive (+) battery post.

5. Prepare Ground Wire: Prepare the ground wire by stripping 5/8″ of insulation. Use a wire of the same gauge as the power connection. Insert the bare wire into the GND terminal and tighten the screw. Prepare the chassis ground by scraping paint and cleaning the area. Strip the other end of the wire, crimp and solder a ring connector, and fasten it to the chassis with a non-anodized screw, star washer, and nut.

6. Prepare Remote Turn-On Wire: Strip 5/8 inch (15.9mm) of insulation from the remote wire. Insert it into the REM terminal and tighten the screw. Connect the other end to a switched 12-volt positive source, typically the source unit’s remote amp turn-on lead.

7. Secure Amplifier: Securely mount the amplifier to the vehicle or amp rack. Avoid mounting on cardboard or plastic panels.

8. Connect Speakers: Connect the car speakers. Speaker impedance for the VCU81 mono block is stable into 1 ohm. For most applications, 18 gauge wire is adequate for speaker leads, but 16 gauge is recommended for leads over ten feet. Pay careful attention to polarity. DO NOT chassis ground any of the speaker leads.

The recommended fuse rating for the CERWIN VEGA VCU81 is 25A.

The CERWIN VEGA VCU81 can be switched on and off using one of three methods, determined by the “Turn-On Mode” switch. NOTE: DC and VOX turn-on settings ONLY work with speaker level input.

• REM: This is the standard 12V trigger wire method. It is the most preferred and reliable method, connecting to the vehicle’s head unit switch output for instant on and off.

• DC (DC offset): When connected via high-level input, this mode senses differences in ground through the speaker leads to turn the amplifier on.

• VOX (signal sensing): This mode will sense any signal input into the amplifier’s RCA and turn it on.

Both VOX and DC will have some delay in turning the amplifier on and off and are used when a 12V trigger wire is not available.

All CVM amplifiers, including the CERWIN VEGA VCU81, work with Cerwin Vega Bluetooth receivers (e.g., BTR7/9/10/12). The BTR will pair to your phone or other Bluetooth device and allow playback through the amplifier. When using a BTR, make sure to set the “TURN-ON MODE” switch on the amplifier to REM.

Since the CERWIN VEGA VCU81 amplifier can accept speaker level input, you can connect it to your radio’s speaker outputs. The easiest way is to buy some stereo RCA cables, cut them, and strip the wires to connect to the OEM amplifier or head unit’s speaker outputs. Then, plug the RCA end directly into the amplifier’s RCA input harness. When using this method, you will need to switch how the amplifier turns on by using the DC or VOX setting on the “Turn-On Mode” switch.

MODEL:	VCU81
RMS Power Rating
	500 W RMS
Max Power
	1000 W
RMS Power (2 Ω)	300 W
RMS Power (4 Ω)	175 W
Bridged (mono 1 Ω)	500 W
Bridged (mono 2 Ω)	300 W
Bridged (mono 4 Ω)	175 W
Type
Topology	Class D
Power Supply
Power Supply	Full PWM
Power Supply Threshold	10.0VDC – 17.0VDC
Idle Current	(0.7A)
Distortion
THD 4 (1KHz @4Ω)	0.5%
S/N Ratio (A weighted @1W)	-85dBA
S/N Ratio (A weighted @ FP)	-101.1dBA
Input Sensitivity
Low Input Level	200mV – 10.0V
High Input Level	200mV – 10.0V
Input Impedance
Low Input Level	20 KΩ
AUX Input Level	20 KΩ
Output Stage
Output Impedance	0.011 Ω
Damping Factor (50Hz @ 4Ω)	>250
Bandwidth (-3dB)	10Hz-350Hz
Crossover (-12dB/Oct)
Variable High-Pass	N/A
Variable Low-Pass	40Hz – 400Hz
Variable Sub-Sonic	10Hz – 55Hz
Fuse Ratings
ATC	25A
Dimensions
Length x Width x Height (inches)	7.7″ x 4.02″ x 1.4″
Length x Width x Height (mm)	195.6 x 102.1″ x 35.5