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the threshold by watching the LED gain-reduction meter, and voilà, you have an automatic level control for the entire system. I found this especially useful for jazz, fusion, and classical music, or very dynamic music with percussion or slap bass that seems to come out of nowhere. By setting a reasonable threshold, I could keep the power amps and speakers running at an extremely high level and let the L-1102 keep the sudden transients and loud passages from either (1) sending me dashing for the mixers output sliders, or (2) listening to the entire system go blaaaaaaaapfrom clipping dis- tortion. Just like its leveler mode, the L-1102s limiter mode does the job silently, quickly, and reliably. I like having two independent processing units in one rack enclosure. Being able to apply one channel as a limiter and one as a leveler is great for mono PA systems; you can use the limiter to preserve your house speakers while setting the leveler to guard the monitors. Its also good for biamplification setups, where you might want to keep tighter reins on, say, your expensive high-frequency drivers. Like the front panel, the L-1102s rear panel is clearly laid out, with both channels busses completely identical. I like the ground- screw terminal, designed so that you can remove its metal shorting piece if ground loops are a problem. Similarly, I like the plastic covers that screw on over the sensing terminals. Im not ex- traordinarily clumsy, but its nice to know that if I were to slip with a screwdriver, I wouldnt be able to short out my power ampsspeaker leads by bumping the sensing screws. Its a small point, but it shows good design on TOAs part. Overall, how does the L-1102 stack up? Very well, not only in terms of how it functions, but in how easy it is to operate. In an age when signal processors are often buried in knobs and switches, its refreshing to use a leveler/limiter thats so straightforward. Its clean, quiet, and well-made. I highly recommend TOAs L-1102 Dual Leveler/Limiter for onstage, studio, and broadcast ap- plications. TOA L- 1102 Dual Leveler/ Limiter Type of unit:Leveler/limiter Features:Two channels that can operate inde- pendently in leveler or limiter modes, stereo linkability, sensing inputs, extremely low noise, single-rack-space configuration Power requirements: AC mains, 50 Hz/60 Hz Power consumption: 14W (120VAC version), or 15W (220/240VAC version) Frequency response:20 Hz to 20kHz (±1dB) Total harmonic distortion:Under 0.1%, 1kHz, rated output; under 0.2% 1kHz, 30dB compression Input:+4dB for 10kΩbalanced load Output:+4dB for 600Ωbalanced load Maximum input level:+20dB Maximum output level:+20dB Sense input: 100kΩ(electronically balanced) Noise level: Under -92dB (IHF-A) Threshold level range: Leveler, -40dB to 0dB (with respect to input); limiter, 1V to 100V RMS (with respect to sense input)Noise gate threshold range:-80dB to -40dB Attack and release times:Dependent on input (or sense input) signal Finish:Black Dimensions: 19" x 1.73" x 12.47" (482.6mm x 44.0mm x 316.8mm) Weight:8.8 lbs (4.4kg) Manufacturers address:TOA Electronics, Inc., 601 Gateway Blvd., Ste. 300, South San Francisco, CA 94080 INSIDE TOA S L- 1102 D UAL L EVELER /L IMITER CH 1 ECHOUTPUT INPUT SENSE+ – ECH + – OUTPUT INPUT From Mixer, Preamp, Etc. Power AmplifierL-1102 Leveler/Limiter To Speaker (THRESH) (10V) (THRESH) (-20dB) POWER AMP OUTPUT OUTPUT OUTPUT: (10) (+20dB) OUTPUT: (0) (0dB) INPUT INPUT -20 -40 0 dB1 10 100 Vrms -20 -400dB A 10:1 Connections for limiter operation (one channel). The wires between the power amps output and the L-1102s sense input are unnecessary when the unit is used as a leveler. The top diagram shows the compression curve of the L-1102 in limiter (speaker protection) mode. Output amplitude is linear with respect to input, up to the threshold (A), and gentle and constant thereafter for compression in the ratio of 10:1. The bottom diagram (leveler) shows compression of an output signal when the input level exceeds a predetermined threshold. The effects of 0dB and +20dB output-level settings are also shown.