With the Dorrough 1200 Stereo Signal Test Set you can take stereo measurements of level, balance, cross-talk and signal-to-noise over the entire dynamic range of your audio system from noise floor to clipping. The set includes a pair of input amplifiers, a 30 dB step precision attenuator, two B scale VU meters (measured in 1 dB increments over a 40 dB range) and two buffered monitor outputs.

The 1200 is a 2U rackmount instrument, allowing instant dynamic monitoring of audio levels, balance, cross-talk, system gain, signal-to-noise ratios and program "center-channel build-up". Verifying proper polarity and balance of stereo broadcast lines is a primary application. Two Loudness Meters are provided. Each feature backlit scales, a dB scale, with 1 dB increments from -36 to +3 dB, and a separate scale for Modulation, from 0 to 125%. Peaks are simultaneously indicated, with lightning speed, as a single LED which rides the crest of the waveform.

Function, Range, and Attenuation controls are set in tandem with the meters to achieve all measurements. Left and right channels are input via loop-thru XLR connectors or a parallel barrier strip. The back-panel also sports a line-level 1/4" stereo output for connection to a scope. A front mounted amplified, stereo headphone jack is also provided for monitoring.