Mechanical Music Digest  Archives
You Are Not Logged In Login/Get New Account
Please Log In. Accounts are free!
Logged In users are granted additional features including a more current version of the Archives and a simplified process for submitting articles.
Home Archives Calendar Gallery Store Links Info
MMD > Archives > May 2012 > 2012.05.04 > 03Prev  Next


Calibrating a Player Piano Tempo Indicator
By John Phillips

Ladies and Gentlemen: I'm pleased to report that the behaviour of
the roll motor in my Steck Half Duo-Art is much improved.  I followed
the suggestions of several MMDers, and made observations of actual
speed versus indicated speed at a range of vacuum levels and made
these tests several times, altering the tension in the motor governor
spring between tests.

I used Excel to plot the results, and this provided a clear view of
how things were improving (or not).  I also ran tests with the motor
running at a constant vacuum level (7" on a water manometer) to get
plots of indicated speed versus actual speed.

I believe the motor is now behaving as well as I can achieve.  It goes
too fast at the lowest speeds on the horizontal dial, and too slowly
at the highest speeds, but these speeds are rarely called for.  In the
middle, the speeds correspond to the dial quite well, and the motor
is almost independent of the vacuum level.

I obtained my vacuum using an old barrel vacuum cleaner running from
an autotransformer.  I'm aware that some people regard this as risky;
however, I've been doing it for years, and the cleaner has never
over-heated.

I believe that I've thanked all my respondents for their advice, but,
just to be sure, thank you again, MMD readers.

John Phillips
Hobart, Tasmania


(Message sent Fri 4 May 2012, 02:34:59 GMT, from time zone GMT+1000.)

Key Words in Subject:  Calibrating, Indicator, Piano, Player, Tempo

Home    Archives    Calendar    Gallery    Store    Links    Info   


Enter text below to search the MMD Website with Google



CONTACT FORM: Click HERE to write to the editor, or to post a message about Mechanical Musical Instruments to the MMD

Unless otherwise noted, all opinions are those of the individual authors and may not represent those of the editors. Compilation copyright 1995-2024 by Jody Kravitz.

Please read our Republication Policy before copying information from or creating links to this web site.

Click HERE to contact the webmaster regarding problems with the website.

Please support publication of the MMD by donating online

Please Support Publication of the MMD with your Generous Donation

Pay via PayPal

No PayPal account required

                                     
Translate This Page