[ Ref. 040504 MMDigest, Gamma of 27-note Barrel Organ

Brian,  From the pictures you sent me, I can tell that this isn't what
I'd call a street organ, it's a fairly large tabletop parlor organ.

You know which end is the bass and treble notes because of the size of
the openings for the reeds.  And you know that the notes are in order
because the openings are progressively larger.  My guess is that there
are about 3 bass notes and then an orderly series or scale of
increasingly higher pitched notes with only one or two sharps.

Since you have the reeds, the tuning shouldn't be a problem.  They are
almost certainly in sequential order, although they will not be
chromatic.  That is, many notes will be missing.  They will probably
not be tuned to 440 pitch, but that doesn't matter.

Make a chart of the scale on graph paper.  Put _all_ the possible
(chromatic) notes across the bottom, in order.  Install the reeds in
order of size and record the pitch of each one.  You can make a small
pressure regulated tuning box if you want to do it out of the organ.

You'll probably notice that the reeds will not all fall right on a
note.  Unless someone has really messed with them, they will tend to be
a bit flat or sharp.  Adjust your tuner so the reed pitches seem to be
close to actual notes.

Say, for example, you do 5 reeds and they are
  A+20C  B+30c  C+10c  C#+55c  D+40c.

Adjust your tuner up about 30 cents so you get
  A-10c  B+0c   C-20c  C#+25c  D+10c

Now the tuner is _roughly_ centered on the notes.

Then plot all the actual notes on the scale above where they appear
to match.  Don't forget to plot the cents, e.g., C#+25c should be
on the vertical C# line, about 1/4 of the distance from C# up to D.
You should get a nice line if someone hasn't tried to file them.

You'll also be able to see the pattern of missing sharps and find any
that are out of order or damaged.   This works on organ pipes too, but
it can be a lot more messy because someone has usually moved the
stoppers and the pipes are always out of tune.

If you still have a problem, I think I know where there is a similar
reed organ.  But I don't want to bother the owner unless you run into
a problem you can't solve simply.

Have fun,
Craig Smith
near Rochester NY  USA