GMS-1390MU Max FX

Select Stereo Effects from Configurable Sixteen Effect Banks

The GMS-1390MU Max FX module uses a digital signal processor to implement high quality stereo effects selected from a bank of sixteen user configurable effects. Samples of 16 bits per channel and 44.1 kHz provide low noise performance and high quality audio throughput. Internal selection of mode through the OLED data display shows the current selected effect and a display of the current control functions.

Panel controls include input level, four program defined controls and a rotary encoder to select the current effect. There is an overload LED to indicate when the maximum input level has been reached. A pushbutton and LED are provided for entering and indicating tempo information. Panel inputs for left and right channel audio inputs and four control voltages are provided. An additional input is provided to allow external control signals to modulate the internal sample clock. Panel audio outputs provide the mix of dry input and effect audio.


Technical Specifications

Operational Modes
Current mode selected from bank of 16 prestored effects

Control Voltage Range
0 V to +5 V

Typical Input Impedance
100K Ohms

Typical Output Impedance
1K Ohms (short circuit protection)

Module Power
+15 Volts 90 mA.
-15 Volts 50 mA.
+5 Volts 75 mA.

Module Size
Panel height - 8.75 inches (222 mm)
Panel width - 2.125 inches (54 mm)
Depth (behind panel) 2.125 inches (54 mm)



We produce electronic synthesizer modules in the two most popular formats, MU (Moog compatible 5U) and EU (Eurorack compatible 3U). A wide range of voltage controlled modules including oscillators, amplifiers, mixers, envelope generators, special effects units, wave generators, filters, power systems and cases allow users complete freedom to configure any desired electronic music instrument.


Grove Audio builds microphones, preamplifiers, equalizers, compressors and other professional audio equipment for performance and studio use. We build units in popular formats such as 19 inch rack mount and 500 series 3U modules. We can also produce custom designs on request. Contact us for a consultation.


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Grove Audio has been manufacturing professional recording and modularized electronics for musicians, performers, and engineers since 1995.