The DXA-8 adapter allows you to attach two balanced XLR type microphones to your camcorder. In addition, an AUX mini-jack gives you the option of using an unbalanced input for the right channel. The input signals are transformer balanced, amplified and sent through a limiter circuit. Finally, the output signals are sent through an isolating transformer for freedom from grounding problems. The attached shielded cable terminates in a stereo mini- plug that connects to your camcorder’s microphone jack.

When the phantom power is activated, the DXA-8 supplies 48 volts to power condenser microphones.

The DXA-8 can accommodate a wide variety of consumer or professional microphones. The gain control allows adjustment for virtually any microphone type and ensures the maximum headroom and the best signal to noise ratio.

A switch lets you select between stereo or mono operation. For stereo operation, the adapter sends the left input signal to the left channel and the right input signal to the right channel. The two channels are never mixed allowing you to access both channels during editing for maximum versatility. For mono operation, both channels are mixed together - ideal when using only one audio source to give you two channel recording.

A ground lift switch labeled G1 / G2 provides either an isolated or connected ground between the adapter chassis and output cable ground.

Operation

Mounting and Connection

Mount the DXA-8 securely to the tripod bushing on the under side of your camcorder. Connect the cable from the DXA-8 to the camcorder’s microphone jack. The camcorder’s onboard microphone should now be disabled. You are now ready to attach external microphones to the adapter.

Power

Install a fresh 9 volt battery in the adapter. Turn on the PWR switch to activate the unit. The LED above the switch should light to indicate good battery power. Turn off power when not in use to conserve battery power

Initial Setup

Set the camcorder to “manual” audio to deactivate the AGC. Turn the gain control on the camcorder to a very low setting – about 20% of maximum. If you later determine that you require more volume, you can increase the camcorder gain. Many camcorders will either have a “peak” indicator to warn of high audio levels or a VU meter or both. If the peak indicator ever comes on, or the VU meter reaches 0 VU, then you will need to decrease the camcorder gain setting to avoid distortion.

Phantom Power

If you are using a condenser microphone that requires phantom power to operate, turn on the switch labeled “48V” for the channel that it is connected to. Dynamic microphones, wireless receivers and connections to mixing boards should not have phantom power activated so be sure that the switch is OFF when using these devices.

MONO / STEREO Switch

Set the switch to MONO if using a single microphone. Set it to STEREO when using two microphones.

Gain Control

Each channel of the DXA-8 has a gain control to provide the optimum amount of amplification for your particular microphone. Note that even with the gain setting fully counter clockwise for minimum gain, you will still get some audio signal.

Set the gain control for the desired volume level on the camcorder. Sensitive condenser type microphones like the popular Sennheiser ME66 will require a minimum amount of gain while most dynamic type microphones require maximum amount of gain. Use the level indicator and your headphones on the camera as a guide. See the limiter description below for information on proper gain setting when the limiter is active.

Limiter

Each channel has an independent limiter to prevent distortion caused by excessively hot inputs. We recommend that this switch be activated at all times to ensure clean, distortion free audio. When activated, the corresponding LMT indicator will flash in proportion to the amount of limiting. Set the gain control so that the indicators are flashing regularly. If they are on continuously, decrease the gain.

Ground Lift Switch

Set the G1/G2 ground switch on the DXA-8 to the position that gives you the least amount of noise. This switch allows the input and output grounds to be isolated to prevent ground noise on some Sony camcorders.

Record

You are now set up and ready to record your audio. By keeping the limiters activated, you can ensure distortion free audio without having to constantly fuss with the audio levels. Happy recording!

©2006 BeachTek Inc.

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BeachTek DXA-8 specifications Operation