electrical interference is a real long shot. i have a CNC milling machine that is doing something similar and is prob ably caused by unshielded signal cables of too close proximity of power and signal cables. it happens only occasionally so it is impossible to diagnose.
another possibility and this is a long shot too especially since the two pedal reliably produce the same results. is there a connector on a cable between a circuit board and the piano action? i don't know if the hammer sensors are connected to an interface board on the piano action ( my first guess) or if there is a cable with wires for each one to the main control circuitry (not a good design and not likely but possible) whatever cable type it might be, it is possible that the movement of the dampers and the key frame shifting might be jiggling this connector. turn off the power before removing or moving any stuff around. look for connectors that might be in a position where they are jiggled by action or damper movement. carefully unplug and re-plug any connectors. do not force anything, there maybe lock tabs on the connectors. figure out how they work and release them before pulling on the connectors too hard. also, if there are similar connectors that might get confused in re-assembly, either take them off one at a time or label them so they will go back in the right positions. when you take off any connectors, it is a good idea to apply a good quality contact lube to them. it can't hurt and it may fix the problem better than just unplugging and replugging. get a cleaner lube such as the one made my MG chemicals thta you can get on Amazon or whoever sells stuff on line where you are. if the cleaner/lube is based on polyphenyl ether it is the best type.
i have been building and repairing electronic devices for about 45 years and have found that electrical contacts are the most common cause of trouble.
as far as i know, removing the piano action is no different from a conventional piano other than some wires connecting the hammer sensors to the rest of the system.
On 4/21/2015 4:55 AM, carl schmidt
carlspost2@... [disklavier] wrote:
Hi again Bill,
Sorry to bother you again about my pesky pedal recording problem. I thought I would give just one last thing a go before I conceded defeat. I think you alluded to it in you previous email. You suggested that there might be something physically interfering with the action and recording solenoids. I did take a look with a torch etc but didnt see anything.
I haven't yet gone as far as sliding out the action to take a closer look. My question is .. does the DKV action slide out just like a normal action - apart from the two electric cables that need disconnecting? Is there anything else that can be easily damaged.? If its pretty straight forward I will have a look -but if it requires specialist handling I will get in the pros...
Cheers, Carl
Thanks anyway, I will check out what you have suggested. However, I dont think it is a light problem as it happens even when the lid is closed. As far as the other ideas... they sound pretty technical so I may end up getting someone in to check it. Cheers.
i do not have a DKV to look at so here are some random things to check. who knows???
is the sustain pedal solenoid or heavy iron trapwork near the E5 key physically or the circuit that reads the hammer sensors? is it possible there is something strange about the hammer sensor for that note or maybe the trapwork some how got adjusted so it is effecting the hammer sensor or the electronics connected to it? could something in the damper tray or stuck on it like a dropped mute or ??? i have no idea how close the damper tray damper wires etc are to the key sensor or if it is possible for something to be moved by the damper mechanism that could be effecting the hammer sensor. be getting into the optical sensor path for the E5 note?
the hammer sensors should be pretty immune to ambient light but is there a bright light shining on the piano that might be reflected into the hammer sensor when the dampers are actuated? does the problem occur if you have all lights off. i once had a strange problem of an optical counter not working properly when the device it was on was used in bright sunlight.
On 4/18/2015 6:56 PM, carlspost2@... [disklavier] wrote:
Hi Bill,
Here are two midi files. The first is me playing nothing but sustain pedal three times. The second file I put the sustain pedal down and then play E fours times about one second apart...
Its quite the conundrum... I have been looking for other causes but have come up with nothing.
Maybe my set up will give you a clue..? I have both a DSR1 and a DKC100R connected . The cable goes from the piano into the DKC100R and then from there to the DSR1 via midi cable then from there to my laptop. Could one be interfering with the other?
Cheers,
Carl
-- Best regards, Spencer Chase 67550-Bell Springs Rd. Garberville, CA 95542 Postal service only. Laytonville, CA 95454 UPS only. Spencer@spencerserolls.com http://www.spencerserolls.com (425) 791-0309
-- Best regards, Spencer Chase 67550-Bell Springs Rd. Garberville, CA 95542 Postal service only. Laytonville, CA 95454 UPS only. Spencer@... http://www.spencerserolls.com (425) 791-0309