The input signal of the Maselec MLA-4 is split into three frequency-bands. Each band is passed through a stereo compressor / expander, where gain and processing can be altered. The outputs of the compressors / expanders are then re-combined and fed to the outputs.
There are four different frequencies for each of the two crossovers that can be separately selected for the low-to-mid and the mid-to-high bands. The three frequency-band compressors / expanders have separate controls so that different parts of the audio spectrum can be adjusted and tuned.
With separate gain controls for each frequency-band, the Maselec MLA-4 can also be used as an equaliser. You can always adjust the controls for the separate frequency bands to different settings.
There is no technical reason why they should be the same for all frequencies. Separate Input and Output gain controls, make the Maselec MLA-4 easy to use for different operating levels.
Inputs
The inputs are electronically balanced, virtually ground floating, making them perform as if they are transformer coupled, but without the associated colouration, low frequency distortion and restricted bandwidth. The input impedance is 100kohm. Maximum input level is >+29dBu (balanced).
Outputs
The outputs are electronically balanced and can deliver >+28dBu into 600ohm (balanced). Output impedance is 33ohm (balanced and unbalanced). The inputs and outputs can be unbalanced by simply grounding either pin 2 or pin 3.
Crossover Frequencies
The crossover between the frequency bands can be set to four different frequencies for both the lower and higher transitions. The filters are passive with 6 dB/octave slopes, which ensure smooth and exceptionally accurate summation of the bands and with minimum colouration and a very flat frequency response.
Master Threshold
Use the Master Threshold to set the point at which the three frequency-band thresholds are in convenient positions for the amount of compression / expansion that you want. CW positions increase the thresholds (which would lead to less gain change).