A3 Adapter

 

The A3 Adapter Connections

The OKM condenser microphones need DC powering. This can be sourced either through a microphone jack present on recording devices or through the enclosed A3 Adapter. The A3 will yield the best results when used on LINE inputs. With its automatic level adaptation, high microphone supply voltage and considerably low noise floor, the A3 offers a significantly greater increase in dynamic range when compared to the conventional direct connection to a microphone jack. When recording faint sounds, the OKM can be used on microphone inputs in conjunction with the A3. However, as a result of the smaller surface area of the microphone membrane, system inherent noise is a possibility. As such, care should be taken to avoid preamp clipping that may occur when the recording level control is set too low.

Connections

The Adapter A3 is plugged in between the microphones and recording equipment. Please bear in mind that you should remove the microphone plug from the A3 Adapter after use. This is to avoid discharging the battery, since plugging the microphone activates the adapter which uses electricity.

Low Frequency Roll Off

The switch position ” /” is to be chosen when recording speech. This attenuates frequencies below 300Hz. The switch position “-” (linear) is chosen to record music.

Linear Attenuation

The switch position “-20dB” is used when recording high sound pressure levels. For moderate SPLs, especially with the A3 on the LINE input, the switch position “0″ is recommended.

Battery Check

To check the remaining battery capacity, press the test knob, which lights up the green LED. The brightness of the LED offers an indication of the remaining battery life time. If the LED extinguishes, please replace the battery.

Extension

When the microphone is placed at some distance from the recording equipment, the microphone cable can be extended, provided that the cable capacity does not exceed 1000 pF. Extending the adapter output cable is not recommended.

Technical Data Adapter A3 ( same as  A3-XLR)

Input impedance                                1 kOhm

Output impedance                             47 kOhm

Frequency response                           20 Hz – 50 kHz (+0 / – 3dB)

Frequency response with filter            300 hz – 50 kHz (+0 / -3 dB)

Max. output voltage                           1,5 V 

Max. output voltage                           1.0 V 

Battery                                              6 V (4LR44 or equivalent)