Antex Electronics DMX-88 USB Recording Mixer - Manual (Page 5)

DMX-88 USB Mixer User Manual
5
There are 8 red/green indicator LEDs on the front of the unit, corresponding to each input channel. The LED will light green to indicate
“activity” when someone is speaking into the microphone. The LED will turn red to indicate that compressor/limiter is active. These
indicators are also mimicked in the Antex Mixer Program, with a 3 color indicator. Green indicates activity, yellow that the
compressor/limiter is active, and red indicates the preamp is clipping.
There is a pair of red and green Device Number LEDs. If more than one DMX-88 is connected to the same computer, each one will
have a different LED pattern to tell them apart. The LED pattern is mimicked in the Antex Mixer Program so the user knows which unit
is being controlled by which Antex Mixer Program instance.
There is a standby mode for reduced power consumption. When the unit is first powered-up, the power LED will flash, indicating
standby mode. All internal electronics are powered down except the USB microcontroller. When the unit is connected to a computer
and enumerates, it will come out of standby and the power LED will stop flashing and glow steadily.
What’s a ”dB” and why should I care?
Throughout this manual, the term “dB” is used. This stands for decibel. You may think, “but I just want to record a legal proceeding.
I don’t want to be a recording engineer. Why should I care about this?” Although dB’s may seem complicated mathematically:
dB = 20 x log(signal level/reference signal level)
Using dB’s gives you a better feel for how changing the volume will sound to your ears. For example, if you increase the output of
your stereo amplifier from 1/10 of a watt to 1 watt, this seems like a small change, only 9/10 of a watt. If you increase the output
from 4 watts to 40 watts, this seems like a real big change. However, in both cases you are increasing the output by 10dB, and
surprisingly, in both cases it will sound to you like the music only got twice as loud.
Negative dB’s means quieter. –10dB sounds half as loud.
Positive dB’s means louder. +10dB sounds twice as loud.
0dB means no change in the loudness when referring to a slider setting. For VU meters, 0dB is the maximum level. Severe distortion
occurs above 0dB.