CARVIN DCM3800L (01) PDF Document

For your protection, please read and follow these safety precautions:

WATER AND MOISTURE: The appliance should not be used near water (e.g., near a bathtub, washbowl, kitchen sink, laundry tub, in a wet basement, or near a swimming pool, etc). Care should be taken so that objects do not fall and liquids are not spilled into the enclosure through openings.

POWER SOURCES: The product should be connected to a power supply only of the type described in the operating instructions or as marked on the appliance.

GROUNDING OR POLARIZATION: Precautions should be taken so that the grounding or polarization is not defeated.

POWER CORD PROTECTION: Power supply cords should be routed so that they are not likely to be walked on or pinched by items placed upon or against them, paying particular attention to cords at plugs, convenience receptacles, and the point where they exit from the appliance.

SERVICING: The user should not attempt to service the appliance beyond that described in the operating instructions. All other servicing should be referred to qualified service personnel.

FUSING: If your unit is equipped with a fuse receptacle, replace only with the same type fuse. Refer to replacement text on the unit for correct fuse type.

U.K. MAIN PLUG WARNING: A molded main plug that has been cut off from the cord is unsafe. NEVER UNDER ANY CIRCUMSTANCES SHOULD YOU INSERT A DAMAGED OR CUT MAIN PLUG INTO A POWER SOCKET.

Avoid spilling liquids or allowing any other foreign matter inside the unit. The panel of your unit can be wiped from time to time with a dry or slightly damp cloth in order to remove dust and bring back the new look. As with all pro gear, avoid prolonged use in caustic environments (salt air). When used in such an environment, be sure the amplifier is adequately protected by a rack, covers, etc.

To wire a Speakon™ connector, follow these steps:

1. Strip the cable insulation back 3/4″. Solder tinned wires 1/4″.

2. Slip the “Securing Hub” then the “Cable Clamp” over the cable before attaching wires.

3. Use the following connection configuration:

– Black (1+): positive

– White (1-): negative

– Red (2+): positive

– Green (2-): negative

4. Solder wires in contacts or use the hex screws provided.

5. Assemble the Twist-Lok Housing, Contact Insert, Cable Clamp, and Securing Hub to complete the connector.

The minimum impedance for the CARVIN DCM3800L is 2 ohms per channel and 4 ohms when bridged.

Follow these steps upon receiving your unit:

1. Inspect your unit for any damage which may have occurred during shipping. If any damage is found, please notify the shipping company and CARVIN immediately.

2. Save the carton & all packing materials. In the event you have to re-ship your unit, always use the original carton and packing material. This will provide the best possible protection during shipment.

3. Save your invoice. It will be required for warranty service if needed in the future.

4. Check for shipment shortage. If you find items missing, they may have been shipped separately. Please allow several days for the rest of your order to arrive before inquiring.

5. Record the serial number on the enclosed warranty card for your records. Keep your portion of the card and return the portion with your name and comments to us.

The sturdy one piece 12 gauge steel face plate accommodates standard 19″ rack installation. The rack mounting holes are designed on ISO standard spacing. Four 10-32x.5″ phillips machine screws are normally used to secure the amp. Rear support brackets are not required.

The RED PROTECT LED provides information about the status of the amplifier. When this LED is on, both channels are muted and the speaker relays disconnect the speakers. The PROTECT LED can activate under 3 different conditions:

1. During power-up: The amplifier stays in a muted state for approx. 3 seconds until it determines that everything is functioning normally. This is normal operation.

2. Excessive current or short circuit: The LED will illuminate if the output load draws excessive current or a direct short is detected. To reset this condition, turn the amp off for two seconds and then on again. Check for shorted cables and ensure the total speaker impedance is not below 2 ohms per channel or 4 ohms bridged.

3. Overheating: This usually occurs when the amp stops in the middle of a performance and the RED PROTECT LED comes on. If this is the cause, leave the amp ON to allow the fan to cool it down. The amp will automatically reset within approximately 3 minutes, and the PROTECT LED will turn off when it is ready. Check for the following potential causes:

– The rear air intake is not restricted.

– The intake air is not extremely warm.

– The front exhaust vents are not restricted.

– There is not an excessive speaker load (try other speakers or remove speakers if you have more than one connected to each channel).

Note: Power supply protections (thermal or over-current) are not indicated by the PROTECT LED; instead, the power will turn off completely. The power supply will reset itself and go through the same turn-on cycle as when first turned on.

A precision input LEVEL attenuator is used to adjust the volume levels. To deliver the amp’s maximum power without reducing the headroom of the signal source, the level controls should be turned full on. For multi-speaker systems, the volume levels can be used to match loudspeakers with different output sensitivity levels and room locations.

SIGNAL, 40% & 80% OUTPUT LEDs: The green SIGNAL LED indicator will start to flash when there is a low input signal (-30dBu). The 40% and 80% LEDs will light up solid when output power has reached 40% and 80% levels respectively.

CLIP INDICATOR: The RED CLIP LED indicators flash when each channel has reached its maximum output. Occasional flashing caused by low frequency peaks is difficult to prevent and will not harm speakers capable of handling the amplifier’s output. However, consistent flashing (indicating excessive clipping/square wave) will damage speakers if the signal level is not reduced. This does not cause damage to the amp.

Upon rack installation, the rear of the amp must be fully exposed to room temperature air. The surrounding air should not be warmer than 120°F with full loading and heavy usage, or the thermal protection could activate early. The front cooling vents are not to be restricted. Air flows from the back to the front. The use of external fans needs to flow in the same direction or the amplifier will starve for air and may overheat.

XLR and 1/4″ TRS INPUTS: The XLR balanced inputs help reduce signal interference and allow longer cable runs. With a balanced input, the gain will be 6 dB higher than using an unbalanced 1/4″ cable. The XLR pin configuration is: Pin 1: Grounded (through GROUND LIFT switch), Pin 2: positive balanced signal, Pin 3: negative balanced signal. The THRU XLR connector passes the signal out for connection to another amplifier’s input.

The 1/4″ TRS jacks are balanced and also designed to receive unbalanced input signals.

PARALLEL “Y” INPUTS: The rear PARALLEL switch connects both channels together from either input, which eliminates the need for Y adapter cables. This is used to “daisy chain” one piece of equipment to another. Just plug into the unused INPUT (TRS or XLR) and it will become the output for other equipment.

INPUT GROUND LIFT: If you experience a “ground loop” which results in audible hum, the input GND LIFT switch (for both TRS & XLR) on the rear panel can help eliminate this problem.

To activate the LIMITERS, engage the rear limiter switch. The built-in limiters are recommended to hold down peaks that could cause clipping. To check the effectiveness, run the amplifier to the point where clipping begins. Then engage the limiters and listen/watch for the reduction of distortion and clipping. If the distortion stops, you can try to turn the channel up for more power until distortion is heard. The lower bass frequencies are most affected. Limiters only affect the signal if the amplifier has entered clipping, so it is best to have the limiters engaged at all times to protect the speakers from excessive clipping.

To set up BRIDGE MODE:

1. With your amp turned off, push “in” the rear (recessed) BRIDGE switch.

2. Connect your speaker to either the center bridge Speakon™ output or the RED binding posts (CH 1 is + and CH 2 is -).

3. Use the channel 1 INPUT and LEVEL control for bridge mode. Channel 2 is not used, except for when using the parallel feature to another amplifier.

4. The minimum speaker impedance is 4 ohms for the CARVIN DCM3800L in bridge mode.

WARNING: No other speaker connectors or binding posts may be used at the same time as the bridge output. Accidental pressing of the bridge switch during operation will cause damage or improper operation. The power developed by bridging your amp can destroy most speakers, so use caution.

SPEAKON™ and 1/4″ COMBO OUTPUTS: The speaker connectors feature a combination of both 1/4″ SPEAKER jacks for low power applications and Speakon™ connectors for high power applications. Secure the Speakon™ connection by turning it to the right to the lock position. The center Speakon™ is for the “Bridge” output only. Always turn the amp off before connecting your speakers.

SPEAKER BINDING POSTS: For bare wire or banana connectors, use the rear BINDING POSTS. Wire sizes up to 7 gauge (50 amps) can be inserted into the binding post “side holes”. Larger cable can be used with “banana” plugs which plug into the end of the binding posts. For BRIDGE speaker connections, use the red binding posts as indicated (CH 1 is +, CH 2 is -).

Your CARVIN DCM3800L is designed to auto switch to either 120V 60 Hz or 240V 50Hz. The voltage range for 120V is 95V to 132V and for 240V is 195V to 255V. The rear heavy-duty AC receptacle will accept a universal grounded AC cord. Be sure to check your power source before plugging into a grounded (3 prong) outlet. Firmly push the AC cord all the way into the receptacle or the amp will not function. Never defeat the grounded connection or electrocution may result.

FUSE: The fuse is located within the main chassis near the AC connector on the PC card. Normally if the fuse fails, the amp will require service. For the CARVIN DCM3800L, the internal fuse is a SLOW BLOW 20A (10A for 240V operation).

NOTE: The CARVIN DCM3800L will require a dedicated circuit breaker for the amp to achieve its full output.

When biamping, you MUST USE an electronic crossover or speaker management system to separate the high and low frequencies. Connect the low frequency output of the crossover to Channel 1 input and the high frequency output to Channel 2 input. Connect your low frequency speakers to the Channel 1 output and your high frequency speakers to the Channel 2 output. Ensure the PARALLEL and BRIDGE switches are in the OFF (OUT) position.

1. NO SOUND FROM CH 2: Check that the rear (recessed) BRIDGE switch has not been inadvertently pushed in.

2. STEREO CHANNELS SOUND THE SAME: Check that the rear PARALLEL switch has not been inadvertently pushed in.

3. NO HIGH FREQUENCIES: Tweeters or midrange drivers may have been damaged or blown from feedback or too much power.

4. SYSTEM HUM: Switch the rear GND LIFT switch IN to reduce hum.

5. POOR SOUND (BASS): The speaker systems may be wired out of phase with each other. To correct this, check the polarity of your wiring and, if necessary, reverse the wires on one speaker connector only. Your sound, especially the bass, will improve.

6. DEDICATED CIRCUIT BREAKER: Your CARVIN DCM3800L will require a dedicated circuit breaker for its full output. There will be a sustained loss of power if the AC voltage falls below the rated 120V or 230/240V input. A 2000w amp or higher would require its own 20 amp circuit to deliver its full power at 2 ohms/channel or 4 ohms bridged.