Voice cards that have not been serviced can result in autotune failing, and the voices not sounding right and inconsistent from voice card to voice card even when autotune succeeds.
The original electrolytic capacitors have long since dried out and stopped performing as they should. I install high quality electrolytic capacitors to replace these failed or failing capacitors and provide decades of stable operation. I use quality, name brand, long life capacitors. Gold audio grade capacitors are provided for the signal path. Also, metal film resistors are provided to replace several key resistors that will improve oscillator stability.
Other component values can change over time as well, so a full calibration of the voice cards is required in connection with installing this kit. One of the challenges in calibrating and tuning the OB-Xa is the cheap single turn trimmer pot used for the initial frequency of the oscillators which makes it very difficult to get the oscillators in tune. I install replacement multiturn trimmers for the initial frequency of Oscillator 1 and Oscillator 2 on each voice card. The precision the multi turn trimmers allow for tuning so precise, it may not be necessary to use the Autotune when the servicing is complete!
This service covers 8 OB-Xa voice cards, and turn time is approximately 1-2 weeks. This does not include repair of any pre-existing defects in your voice card(s) other than the components mentioned.
While you’re sending your boards, also consider our power supply service.