Each pre-amplifier is also equipped with a high quality protection circuit with variable threshold, to protect recorders or amplifiers from overload and consequent distortion. The control paths of any or all SoftStopTM protectors may be linked in pairs to prevent image shifting in stereo or surround sound recordings.

Operating levels of either +4dBu or -10dBV may be selected for outputs B and C. The DB8000s is rack-mounting and internally powered.

Pre-amplifiers

Each channel has a 12 position switched GAIN control, giving up to 66dB of gain. The Pad switch gives 20dB attenuation, while a separate TRIM control provides -14dB to +6 dB of gain. The balanced input provides a high level of common mode rejection and the equivalent input noise is better than -128dBm unweighted at all gains.

Individual switches (with LED indication) select 48V phantom power and phase reverse. The 80Hz high pass filter may be switched in to remove unwanted low frequency handling and other noise.

Mid & side

Channels 1 and 2 may be used in conjunction with M/S (Mid and Side) microphones, to provide a decoded stereo signal at their outputs. The Mid mic is connected to Channel 1, the Side mic is connected Channel 2 and the M&S button on Channel 2 is pressed. Channel 1 provides the decoded left hand signal while Channel 2 provides the decoded right hand signal. Varying the relative levels of Mid and Side allows the spatial width of the decoded stereo to be varied. Channels 3 and 4, 5 and 6, 7 and 8 may similarly be used for additional M/S set-ups.

Protection

Pressing the SoftStopTM ON switch allows a threshold to be set anywhere from -6dBu to +21dBu, referenced to the selected output operating level. A signal approaching overload is gently compressed but if it exceeds the threshold it is effectively clamped to prevent the level rising further. For stereo, M&S or surround sound operation the SoftStopTM side chains may be linked.

Metering

Peak-reading bargraphs with peak-hold, display signal level relative to the selected output operating level of either +4dBu or -10dBV.

Outputs

Each microphone pre-amplifier output is electronically balanced and can drive cables up to 100 metres in length. A switch on the rear of each channel sets outputs B and C to the -10dBV operating standard.

Stereo Width Management

The DB8000s can be used to widen or narrow the sound stage of previously recorded stereo signals. Feeding the stereo signal into Channels 1 and 2, the outputs of which are fed into Channels 3 and 4, configures the M&S circuitry as a WHIPTM matrix. Channel 4's TRIM control then varies the stereo width from mono, through stereo to wide stereo without phasing or "hole in the middle" effects.

Power

The unit has an extremely low noise and hum field internal mains power supply, making the DB8000s completely self-contained. Mains voltage may be specified for either the European 230V standard or for 100-120V.

Mechanical

The DB8000s is housed in a standard 19" rack case, 3U high by 205mm deep.

The DB8000s will be available from July 2001.