Troubleshooting Your Prophet ’08


The list below provides solutions to some of the most common tech support issues.

Encoder Issues

A few years back, there was an issue with some of the encoders used on the Prophet ’08 keyboard and module. We received some bad parts from our supplier that were mixed in our shipments for a short period of time. These encoders in question have a shorter lifetime than their specification, causing problems with some of our synths in the field. Please note that this does not affect all units. To read the full explanation from Dave, click here.

Resetting Global Parameters and Calibrating Your Prophet ’08

If you are having problems with your Prophet ’08, resetting the Global parameters is a good place to start.

To reset the Global parameters:

  • Hold down the Global button and LFO 3. This sets the Global parameters back to their factory defaults. (There is no full hardware reset built in, but the factory programs are available for download if you want to get everything back to the original state.)

If one of the analog waveshapes sounds strange or if a filter is not behaving as expected, you may also want to try running the calibration routine. This is not something you should have to do regularly (or ever, really) and has no effect on the oscillator tuning.

To run the calibration routine:

  • Hold down Global and press LFO 2.
If your Prophet ’08 Keyboard is not tuned to concert pitch:

You may need to calibrate the wheels.

To calibrate the wheels:

  1. Turn the mod wheel all the way off (down), and while also holding the pitch wheel off, hold down Global and press the Mod 1 button.
  2. Return the pitch wheel to center, and hold Global and press Mod 2.
  3. Move the Mod wheel all the way on (up), and while also holding the pitch wheel all the way on, hold Global and press Mod 3.
If the left channel is louder than the right:

Update your OS and use the BalanceTweak parameter in the Global menu to adjust the left/right balance.

If some voices are louder than others:

Are you using both the Left and Right outputs? The Prophet ’08 does not have a mono output, though you can turn all the panning controls off in a program and effectively turn both outputs into mono outs. (Note that there is a production error in the very earliest Prophet ’08 Keyboards where the Main Left output is labelled “Left/Mono.” This is incorrect and has been changed in subsequent production runs.) A soon-to-be-released version of the OS (versions above Main 1.3 Keyboard/Main 1.4 Module) includes the ability to globally switch between stereo and mono.

If voices 1 through 4 don’t sound:

Are your audio cables plugged into the Main outputs? If you plug into the B outputs, voices 5 through 8 are removed from the Main outputs and only voices 5 through 8 play through the B outputs.

If the sequencer and arpeggiator have stopped working:

Make sure the MIDI Clock setting in the Global menu is set to Internal. If it is set to MIDI In or MIDI In/Out, the sequencer and arpeggiator will only play if a MIDI clock is present at the MIDI input.

If some of the programs sound different than they usually do:

See previous.

If key assignment seems strange and it skips notes when you’re playing:

Make sure poly chain is turned off in the Global menu.

If you hear clipping distortion in some of the factory programs:

There are many sources of gain in the Prophet. If they are set to high levels, you might hear some distortion under the right circumstances. We try our best to make sure that doesn’t happen on the factory programs, but we’re never going to be able to predict just how someone else will decide to use them (which is part of the fun of making synthesizers). Start by reducing the Amp Envelope Amount.