1.) Pressing the COUPLE switch  links the channels

2.) Use the TRIGGER control in the expander/ gate section to determine the threshold below which expansion sets in,so that signals below threshold are reduced in gain.

3.) If a signal below the adjusted value is applied,the red LED lights up.If the signal gain is above the  adjusted value,the green LED lights up

4.) In order to adapt the expander optimally to the program material,use the RELEASE switch to select a short or long release time.

5.) The GATE switch allows you to toggle between the expander and the gate function

6.) Use the THRESHOLD control to adjust the compressor threshold from  -40 to +20 dB.

7.) These three LED's indicate whether the input signal is above or below the adjusted compressor threshold.

8.) Activating the SC EXT switch interrupts the link between the signal input and the compressor control section.

9.) The SC MON switch links the sidechain input signal to the audio output,thereby muting the audio input signal.

10.) The RATIO control determines the ratio of inputs vs. output level with regard to all signals exceeding threshold by more than 10 dB.

11.) The 12-digit GAIN REDUCTION display informs you about the current gain reduction applied

12.) The LO CONTOUR switch activates a high-pass filter in the side-chain path and thus avoids the "pumping" effect caused by high-energy bass frequencies and their influence on the compression process.

13.) Use the ATTACK control to determine when the compression sets in once the signal has exceeded threshold.

14.)  Press the INTERACTIVE KNEE switch to change from "hard knee" to IKA characteristic: Input signals exceeding threshold by up to 10 dB will be processed wit a "soft knee" characteristic.

15.) The AUTO function which is activated with the AUTO switch,disables the ATTACK and RELEASE controls and derives these time values automatically from the program material.

16) The RELEASE control sets the time when the original 1:1 gain is reached,after the signal has dropped below threshold again.

17.) Use the TUBE switch (MDX2600 only) to enhance the output signal with the warm and transparent tonal character typically produced by electronic tubes.

18.) The OUTPUT control allows you to raise or lower the output signal by max 20 dB , so as to make up for a gain loss caused by the compressor or limiter action

19.) The 12-digit INPUT/OUTPUT LEVEL display reads both the level of the incoming audio signal and the level at the dynamics processor output.

20.) The IN/OUT Meter  selects whether the gain LEDs read the input signal or the output signal

21.) The IN/OUT switch activates the corresponding channel.