Disklavier

Hello all,

I think that Robert has got the limitations of the Disklavier just about
right. Some academic researchers published a paper on the accuracy of
the (Mark II) Disklavier last year. They found that the accuracy of the
recording was better than the accuracy of the playback. In particular
the timing accuracy of the playback of soft notes was poor and the
solenoids did not reproduce high midi velocities (there's no audible
difference between a midi velocity of 100 and 120). 
        If anyone's interested in the full details there's a paper
online with full details of their measurements at http://ftp.ai.univie.a
c.at/papers/oefai-tr-2001-27.pdf.
        The original query related to piano roll conversions played back
on the Disklavier. Piano rolls had their own timing problems and I'd
have thought that timing problems are much more likely to be a function
of the original roll (and its conversion to midi) than errors produced
by the Disklavier.
Hope this is helpful
Mick
>
>You are quite correct that there are measurable errors in the recording 
>and reproduction of the Disklavier Mark II.  At least that is what I 
>have found on mine.  The regulation of my Mark II has been maintained to 
>the satisfaction of my RPT and the keyboard and pedal calibrations have 
>been  periodically performed.  The measurable discrepancies between what 
>is played and what is reproduced are not limited to timing, but also 
>include loudness.
>
>Also, the same file played twice or more consecutively, reproduces 
>slightly differently each time, both in loudness and timing.
>
>The magnitude of the errors (that I have found on mine) is generally 
>dependent on the note velocity.  For example, with the Volume control 
>set to "0", notes that were recorded at a velocity of about 100 are 
>reproduced with a sound power from 1 to 4 dB softer than what was 
>played; notes that were recorded at a velocity of about 25 are 
>reproduced at a sound power of from 1 to 5 dB louder than what was 
>played; notes that were recorded at a velocity of about 60 are 
>reproduced at a sound power of from 0.5 to 2 dB louder than what was 
>played.
>
>With the Volume control set to "0", the sound output limits for note 
>velocity values from 93 to 127--that is, there will be no difference in 
>the loudness of a particular note whether its velocity is 93, 110, or 
>127.  In order to hear those gradations in dynamics, you would need to 
>set the Volume control to "-4".
>
>Once again, the magnitude of error may or may not be noticeable, 
>depending upon what is being played and who is listening.  Maximizing 
>the profit of a product evidently doesn't require satisfying the most 
>astute consumer.
>
>Unfortunately, judging accuracy by ear is a very subjective process. If 
>you are going to try that, and if you wish to approach the truth, I 
>suggest a "blind" test wherein the evaluators do not know whether they 
>are listening to an original performance or to a reproduction and can 
>only sort them out later through coded names.
>
>A comment on playing the old PianoSoft disks on the Pro:  The 
>information that a Pro recording includes--that is the fine continuous 
>time record of the key and pedal positions--is absent in an old 
>PianoSoft disk.  Without the benefit of that information, the Pro's 
>potential for accurate reproduction cannot be exploited.  To truly 
>evaluate the Pro, you must listen to a Pro with a Pro recording.  A 
>PianoSoft file cannot do it justice.
>
>Yamaha surely knows its market which is probably why they have focused 
>on the XG and now the CD features.  However, why, after developing the 
>Pro and bringing it to market several years ago, Yamaha has not 
>commissioned solo re-recordings targeted at Pro owners simply confounds me.
>
>--Bob Welcyng
>
>
>
-- 
mick hamer