Reading a Dorrough Meter

A Dorrough Loudness Monitor is roughly analogous to a "PPM" and a "VU" combined, but with more complimentary ballistics assigned to each parameter. The result is an established relationship between the PEAK and the RMS content. When riding gain for balanced loudness, PEAKS should be driven to the brink of the top set of three red LEDs, while the RMS
  should be driven to the brink of the center set of 3 red LEDs, or whichever event happens first in time. This is defined as RELATIVE LOUDNESS, in one dB steps from source to source. More simply put, whenever an operator sees red, he or she should pull levels back slightly!
"The best way to practically demonstrate the Loudness Monitor is to build a mix, adding instrument after instrument. As you bring up the level a lone snare-drum will send only the lead PEAK LED across the scale. On a typical VU averaging meter that sound will only register as a slight wiggle. A PPM meter might do better with the percussion, but what if that snare was mixed with some strings? The PPM would be relatively oblivious to the building density behind the beat. With the Dorrough meter's "Practical Standard Ballistics", as instruments are layered-in, watch a contiguous group of LEDs build-up behind   the PEAK indicator. You can actually see the "density" of the sound, all the while maintaining the ability to protect the peak of the waveform. The advantages of these new devices are so compelling that audio engineers all over the world are abandoning long cherished notions about the immutability of old standards. Expensive studio time, demanding artists and increasing numbers of recording and location situations, that often preclude re-takes, make the Practical Standard Loudness Monitor an indispensable tool."
    Mike Dorrough
Dorrough produces a variety of digital audio meters, video meters, surround sound meters, and audio and video test products.
One year warranty is standard on all Dorrough products.
The company is located at 5221 Collier Place, Woodland Hills, California 91364 • Telephone (818) 998-2824. Fax: (818) 998-1507. Email: