> Subject: 'O'-roll scale questions
>
> .........................................................................
> Background:
> The listings in the 'Encyclopedia' show *piano-based* 'O'-roll scales
> with:
>   'Principal' (P) instrument = flute/pipes, and
>   'Secondary' (S) instrument = bells/xylophone.
> It is a 'given' that the piano plays all of the time.

  Only the accompaniment piano plays all the time. When either a P or S
  is on, a pneumatic lowers a heavy felt rail which restricts the piano
  hammers over the 24 note section known as the "solo" section. You
  might also accomplish this by dividing the stack similar to the way
  the Seeburg H accomplishes its solos.
  .........................................................................

> Questions relative to 'typical' O-roll arrangements:
>
> 1. Do both the P and S instruments use the same range of notes
>    (piano #62-85) for solos? Are they merely alternate sets of solo
>    instruments?

          Yes!

> 2. Is the piano always intended to be 'damped' in the solo range during
>    solos? For both P _and_ S?

          In the case of P yes.  And I have seen some exceptions with S,
but they may just be lock (on) perforations that escaped
the editor.

> 3. Is the piano damper's lock-and-cancel activated by both 'P' and 'S'?

          It should be.

> 4. What about non-piano-based devices? Ex: Pipes/accordion/bells, or
>    air calliope/bells.  Should the 'Pipes' play all of the time and the
>    'Principal' instrument be ignored? (since the 'swell'-if connected-is
>    controlled by P at hole #'s 13 & 19).

           In the case of old original instruments like the style SO and CO,
when two ranks of pipes were used (SO), the violins and flutes
were turned on together. I would suggest experimenting with
combinations of control holes (such as pipes on, mandolin off;
pipes off, mandolin on.) depending upon the listenability of
what instruments you are using.

> 5. Do typical 'O'-rolls make better use of P or S as solo instrument?

           No. The best arrangements in my opinion are those cut in
the 1930's when the market for the machines had pretty much
evaporated.  Most earlier O-roll arrangements are strictly
commercial grind-outs.

           Goodluck with your endeavors.

Stephen Kent Goodman