OB-6 Keyboard Troubleshooting 28 April 2022 13:24 Updated If the unit is not booting: CHECK BOOTLOADER OPERATION AND RELOAD OS Hold WRITE and apply power to the instrument. A rotating animation will be shown on screen indicating bootloader mode is active. Send the main OS file to the synth via MIDI IN port (USB cannot be used in bootloader). OS file and installation instructions If the unit boots but has an issue, perform initial settings first: INITIAL SETTINGS Start by removing all connections (MIDI/USB, pedals, audio) from the rear of the instrument except for power. Reset global parameters: hold GLOBAL and press WRITE. No confirmation of the reset will be shown on-screen, but the global parameters will be set to the factory default. Press GLOBAL twice to exit the global menu. Initialize a basic program: hold MANUAL and press WRITE. Connect a set of headphones to the headphone output. Next, proceed to the appropriate section below according to the issue described: I. Audio Issues (voices not triggering or not sounding correctly) A. Perform Initial Settings Verify if the issue is still present. If so, proceed to step B. B. Oscillator/Filter Calibration Start Calibration: Hold MANUAL and press 0. Calibration will start and progress will be shown on the screen. If calibration stalls/does not complete, take note of the text on the display. If calibration completes and no problem is detected, reconnect audio cables to the instrument’s main outputs. Verify if the issue is still present. If so, proceed to sections C, D, E, or F based on problem description. C. Some Voices Sound Quiet, Compare to Others If the problem is only present with a single cable connected to the main output, set PAN SPREAD to minimum. *PAN SPREAD sequentially pans the voices further into the stereo field left to right as the voice count increase. If only a single cable is connected to the main outputs, voices panned to the opposite side will sound more quietly. D. Distortion In Audio Outputs Is distortion present on headphone output? If so, try turning down the AMP ENVELOPE AMOUNT. If no distortion is present on headphone output, verify correct cables are in use (TS unbalanced) and that the instrument is connected to the appropriate audio interface/mixer input (Line level input). If distortion is still present, check the instrument with another set of cables and audio interface/mixer inputs. If distortion is still present on the Main L/R outputs, reduce MASTER VOLUME to below 50%. If distortion ceases, this indicates that repair is necessary. E. Filter Cutoff Having No Effect Connect an expression pedal to the filter input port at the rear of the instrument. Set expression pedal to the minimum level and power instrument off. Remove the expression pedal from the port while the pedal is still at minimum setting. F. Output Level Mismatch Differences in output level between the left and right main outputs of 1-2dB are within expected tolerances. This is due to the analog nature of the amplifier circuitry in our instruments. II. Tuning Issues A. Perform Initial Settings Verify if the issue is still present. If so, proceed to B and C. If the issue is still present after steps B and C, proceed to step D. B. Wheel Calibration Set the mod wheel and pitch wheel to their minimum setting. While still holding the pitch wheel down, hold MANUAL and press 7. Release the pitch wheel to the center. Hold MANUAL and press 8. Set the mod wheel and pitch wheel to their maximum setting. While still holding the pitch wheel up, hold MANUAL and press 9. C. Oscillator/Filter Calibration Start Calibration: Hold MANUAL and press 0. Wait for the routine to finish. Check if the tuning is immediately better after completing calibration. If so, run calibration over a larger range of operating temperatures. Repeat calibration whenever you notice tuning instability: upon power on, after it's being on for a period of time, and when there is any environmental/temperature change. Over time and as a larger number of calibrations are run, you should not need to calibrate as often. **If calibration does not complete successfully, check the FILTER input on the rear of the unit. If a pedal is connected, remove the pedal are attempt calibration again.** D. Clear Oscillator/Filter Calibration Clear Calibration: Hold MANUAL and press 3. *Note that no on-screen confirmation of the clearing will be displayed. After clearing calibration data, you will need to run calibration extensively to stabilize the tuning. III. MIDI Issues A. Perform Initial Settings Verify if the issue is still present. If so, depending on the description of the problem, proceed to step B, C, D. B. Instrument Not Outputting MIDI Press GLOBAL once, then press 9 to select MIDI OUT and verify it is set to the port being used to transmit MIDI data. If it is not set to the correct port, use the INC/DEC buttons to set MIDI OUT to USB or MIDI. Press GLOBAL twice to exit globals. C. Instrument's Voice Count is Halved This is due to a MIDI feedback loop. When the synth is actively connected to a DAW via USB or MIDI, turn LOCAL CONTROL off with steps 2-4. Press the GLOBAL button twice, then press 0 to select LOCAL CONTROL. Use the INC/DEC buttons to set LOCAL CONTROL OFF. Press GLOBAL once to exit globals. D. Pots/Encoders Not Updating Correctly This is due to a MIDI feedback loop. When the synth is actively connected to a DAW via USB or MIDI, turn LOCAL CONTROL off with steps C2-4. IV. Button Issues A. Perform Initial Settings Verify if the issue is still present. If so, proceed to step B. B. Switch Cleaning Routine The switches on our instruments are self-cleaning. In most cases, buttons that are intermittent/non-operative can be resolved by being fully depressed 50-100 times. If the operation improves but is still intermittent, repeat step B1. V. Pot/Encoder Issues A. Perform Initial Settings Verify if the issue is still present. If so, depending on the description of the problem, proceed to step B, C, D. B. Pot/parameter Value Changes On Its Own Turn the pot back and forth across its full range of travel 10-20 times. Set pot to minimum or maximum setting and check whether pot/parameter continues to change on its own. If it does not, set the pot to its midpoint and check whether the pot/parameter continues to change on its own. If the parameter continues to change on its own, the pot requires replacement. C. Encoder Value Does Not Update On Every Detent Due to the manner in which the encoders are scanned, it is possible for an encoder to not update a value for 1-2 detents. This is within expected tolerances and is not considered a fault. D. Pot Feels Wobbly Excessive horizontal pressure applied to a pot may cause the pot shaft to loosen within the housing of the pot’s enclosure. It is advised to not apply excessive non-axial force when turning a pot. If the pot works correctly to set value (no jumps in value or value change without physical movement), then the pot is working correctly and no fault is present. VI. Keybed Issues A. Perform Initial Settings Verify if the issue is still present. If so, proceed to step B. B. Key Contact Cleaning Fully depress the key in question. Press the key into the aftertouch circuit with a good deal of force. Wiggle the key and release. Repeat steps 1-3 until the key operates as expected. Related articles OB-6 Module Troubleshooting Prophet-6 Keyboard Troubleshooting Prophet-5/10 Keyboard Troubleshooting Backing Up User Sounds Over MIDI Welcome!