Headphone Output

with satellite transmission systems, are present. In effect the Model 233’s sidetone function adds the “minus” part to a “mix minus” cue.

Several configurable parameters allow the sidetone function to be tailored to the needs of a specific Model 233 installation. The sidetone function can be configured to route audio to the left, right, or left and right headphone outputs. It can also be completely disabled. Sidetone can also be configured to be active only when the main output is active, or to be active anytime the main output or either of the talkback outputs is active.

Three rotary controls are provided for user adjustment of the headphone output. Two of the controls adjust the levels of the externally connected sources. The third control is used to set the level of the side- tone function.

For flexibility the actual functioning of the two controls associated with the external sources is configurable. For traditional on-air sports applications they can be selected to the dual level control mode which provides independent control of the left and right channel volume. For use with stereo cue signals, or to support user pref- erence, the level/balance mode can be selected. In this mode one control adjusts the overall level of both the left and right channels, while the other allows adjust- ment of the left/right level balance. To help minimize the chance of broadcast cues being missed, both level control modes can be configured so that a minimum headphone output level is maintained. Alternately, the headphone output can be set to fully mute when these controls are at their minimum position.

A headphone control reverse mode is provided specifically for on-air television applications where a headset with boom microphone is used. The reverse mode ensures that no matter which headset orientation is used by the talent, the two “pots” controlling the external sources will always work intuitively. This will result in a comfortable work environment, allowing the “left” control to impact the level to the talent’s left ear while the “right” control impacts the right.

The sidetone level control is dedicated to adjusting the level of the mic audio signal that’s routed to the headphone outputs.

Configuration switches allow which of the headphone outputs—left, right, or both— will receive the sidetone signal. When the sidetone level control is set to its minimum position the sidetone level is always set to be fully muted.

Provision has been made to support ap- plications where a monaural cue feed is desired. A configuration switch allows the summing (combining) of the selected left and right headphone sources. In addition to creating a dual-channel mono output it also allows the level controls to be config- ured as a simple 3-channel mixer.

The headphone output is optimized to meet the needs of contemporary head- phones and headsets. Specifically, the output circuits act as voltage, rather than power, drivers. In this configuration they can provide high output levels with very low distortion and noise, along with mini- mal current consumption. The output cir- cuits are configured to safely drive stereo or mono loads. This ensures that all types of headphones, headsets, and earpieces can be directly connected.

Model 233 User Guide	Issue 1, September 2007
Studio Technologies, Inc.	Page 9