The MKS-50 has the classic synth-string and brass sounds down, and even does a good job with organs and vocal sounding pads. It can also produce some zaney effects and suprisingly realistic (okay, for an analog synth) timpani and steel drum. Just about any sound from warm and mellow to edgy to filter-sweeping techno can be created. The factory sounds of the unit belie its true prowess. I found the MKS-50 useful in layering with other sounds, and alone, providing great synth bass sounds for a track. The unit can certainly hold its own when compared to other units on the market.
The MKS-50 can hold 128 patches, each patch containing a "tone", controller parameters, pitch bend range, voice mode, and chord functions. A tone contains all oscillator, envelope, LFO, and filter parameters. The oscillator section has several different waveforms available for individual or simultaneous use: PWM with speed and depth programmable independent of the LFO and saw tooth wave with several variations. A noise source is available as is a sub oscillator each with four selectable amplitude levels. (off, 1, 2, 3) Modulation sources are autobend with programmable depth and LFO modulation also with programmable depth. The combined signal from the oscillators feed the filter section with variable cutoff and resonance. The filter has a medium slope and a nice warm sound. Resonance can be dialed in and is consistent from step to step. The filter cannot be forced into self oscillation, which is a shame, since it can make for more interesting sounds. The filter can be modulated by the LFO, envelope generator, and key velocity. (Called "dynamic" modulation by Roland) Filter modulation by the LFO can be programmed individually, but EG and dynamic modulation are contolled by the same parameter. The filter modulation can be set to "dynamic", "dynamic EG", "inverse EG", or "EG". It would have been nice to have dynamic inverse available, but having inverse available at all opens up new possibilities. The next set of parameters controls the VCA and how it is modulated. An overall level control is available, and the modulation is similar to that in the filter section. That is, amplitude is controlled by "dynamic", "dynamic EG", "inverse EG", and "EG". By now you may have wondered why I have not mentioned the envelope control for each of the sections. This is due to the MKS-50 only having one envelope, the trade off is that it is of the four stage time-level variety. At first I found this limiting, but in time, and with a little more finesse, I was able to create most of the sounds I was aiming for.
The PG-300 is the companion programmer for the MKS-50. It provides hardware control of all the parameters contained within a tone. I find it a must for programming the unit, and great for tweaking sounds on the fly. My only caveat is that the PG-300 defaults to MIDI channel 1 on power up. The PG-300s are becoming somewhat scarce, so seize the opportunity to grab one when you can.

To change the PG-300's MIDI transmit channel, set the Sub Osc Level and Noise Level sliders according to the chart below, and turn on the power on while holding the Manual button.

      midi channel   01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16
      sub osc level   0  0  0  0  1  1  1  1  2  2  2  2  3  3  3  3
      noise level     0  1  2  3  0  1  2  3  0  1  2  3  0  1  2  3


Roland MKS-50 and PG-300 Owner's Manuals
Roland MKS-50 Synth
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