Posted by: carlspost
Pianodisc iPad Air - 04/14/14 08:13 AM
I am looking at installing a Pianodic system into my 1974 Yamaha C7. I have been told the iPad Air version is the way to go. I also want to install Prorecord. Being a classical pianist, I am not really interested in all the extra features (sing along, sync-a-vision etc etc) What I am most interested in is the systems ability to record and reproduce as faithfully as possible. I have seen lots of videos on the internet showing the system working but they all seem to to be of 'light' style music.
Does anyone know how the Pianodisc with prorecord would handle some pretty intense classical repertoire in terms of note repetition, dynamic variations?? ie Debussy, Rachmaninoff, Prokofiev etc ..Any advice is much appreciated.
I've seen a lot of hype about the ProRecord system. I am also interested in hearing any feedback from this new record component. I have a instrument rental company here that I installed the TFT record strip about a month before the ProRecord came out. I wondering if the latter would be better in commercial and recording situations.
Posted by: Mark Fontana
Re: Pianodisc iPad Air - 06/07/14 05:50 AM
PianoDisc's TFT and ProRecord systems (and QRS' PNOscan) sense only key motion, which does not always correlate well with hammer velocity due to the complexity of the piano action and its escapement mechanism. This is why higher-end electronic reproducing pianos (including the Disklavier, Bosendorfer SE and CEUS) use optical shutters on the hammer shanks breaking light beams to measure the velocity of each hammer just before it hits the string-- the tried and true technique that has been used for over 30 years. Installing this technology isn't feasible for retrofit player kits, though, which is why they have settled on key motion sensing as being good enough, even though the patents on the more accurate method are expired. What's surprising is that PianoDisc doesn't offer a more accurate recording system in their Mason & Hamlin pianos, for which a factory installation is possible. It could be for marketing reasons, as doing so would imply that ProRecord isn't the pinnacle of accuracy it is claimed to be.
The reflective sensing of key motion has a number of engineering pitfalls in addition to the poor correlation with hammer velocity, among them being the temperature sensitivity of phototransistors and the dimming of the emitter LEDs over time due to aging and the accumulation of dust on the upward-facing components. Darkening over time of the reflective surface of the key bottoms is yet another factor affecting calibration, as well as crosstalk between adjacent keys.
With that said, these reflective systems achieve results that may be perfectly adequate for many people, so there is definitely a market for them. I just don't think they're suitable for professional use or making recordings of great pianists for posterity.
Relative to why PianoDisc would not offer a special version of ProRecord III installed at the factory on new Mason & Hamlin (M&H) Pianos - Your comment is pointing out the fact that although ProRecord III uses optical TFT, the best (albeit more expensive) approach would be to additionally use optical shutters to measure hammer velocity at the source, in order to compensate for changes in humidity, temperature, flex/dynamic stiffness variation in the action, etc. But one thing that all new M&H's have in common is their new carbon fiber / nylon composite Wessell, Nickel & Gross (WNG) actions. These new actions are amazingly quick and consistent - undeniably the best I've ever played. BTW, Steingraeber now offers it as an added cost option, and Bosendorfer utilizes the WNG action in their state of the art Phoenix 275 Concert Grand Piano.
Each of the three superb Mason & Hamlin 7'0" Semi-Concert Grand Model BB's I played during a recent M&H factory tour felt very similar to me from an action point of view. (Yes - I am about to be a proud new owner of a M&H Polished Ebony 7'0" Model BB with PianoDisc HD iQ and ProRecord III !) Bruce Clark - the Chief Engineer for M&H and WNG, mentioned to me that the stiffness of each key is identical to the "stiffest" hornbeam wood shaft and has a variation of less than 0.5% due to the carbon fiber material used. This as opposed to shafts that typically vary in the 5% to 20% range and even up to 40% (6 sigma) note to note on a wood action piano. Piano technicians typically make up for these differences (initially in added key weights or) by voicing of the hammers during regulation. In addition, the WNG actions (which need only one key weight vs up to three for other actions) are unchanged by temperature and humidity and have been tested internally to outlive wood actions by over 10x (awesome for pianos that are reproducing player pianos). So I think the feeling at M&H and PianoDisc is that the added cost of adding a Disklavier or Spirio-like velocity feedback for ProRecord III is a somewhat unnecessary cost for installation on new M&H pianos, which are all equipped with WNG actions. Using optical shutters in addition to optical TFT sensors only adds to long term service & maintenance and decreased reliability (more sensors/less reliable - that's why nobody is doing closed-loop position right now outside of the SE). The M&H WNG dynamics are known and can be accounted for by the software, after calibration. Just a different perspective than pushing optical TFT as "State of the Art" for marketing reasons only?