tuning continuo pipe organ by ear

> Re: Goldberg in squiggle <#5a> From: Cameron Bobro > > > On this
> > > > particular organ the tuning is done by moving stoppers, shades,
> or
> > > > sleeves. We tuned 200 pipes in about 90 minutes;
> > >
> > > What's the range of tuning on an organ like this?
> > >
> >
> > By "the range" do you mean the keyboard compass? Single manual, 50
> > notes from C up to d'''. We tuned the 8, 4, 2, and 1 1/3 foot ranks.
> > I meant, how much can you tune/detune each pipe?

I don't know what you mean by "detune" here, for sure (synthesizer terminology??), but I assume you're asking about how much each pipe's pitch can be raised or lowered off some central average point.

On this particular organ, the open 4' flutes tuned by shades could be adjusted by approximately 1/4 step in either direction: by making the shade go straighter up or more tightly bent across the opening.

The sleeved open 2' and 1 1/3' have a little bit more range than that, depending how long their sleeve is.

The stopped 8' flute has about 1/4 step of leeway downward in pitch (i.e. pulling the stopper up farther), but a huge possible range upward, on the same principle as a slide whistle; depends how much excess there was to the pipe's length to begin with. It can only be pulled out so far, lowering the pitch, before it pops out the end...but it can pushed down into there as far as one can force it to go, raising the pitch. It just has to make a tight enough seal, wherever it is.

As I said before, we did this all by ear, not by measuring any cents on an electronic device.

We did briefly try to measure a few of the 4' flute notes at the beginning of the session, but their pitch was fluctuating all over the place while holding a steady note. This is normal. Somebody can probably say more about the usual chaos in the wind of a shaded pipe or a stopped pipe. The open metal pipes (sleeved) were considerably steadier.

Brad Lehman

--- In tuning@yahoogroups.com, Brad Lehman <bpl@...> wrote:
>
> > Re: Goldberg in squiggle <#5a> From: Cameron Bobro
> > > > On this
> > > > > particular organ the tuning is done by moving
stoppers, shades,
> > or
> > > > > sleeves. We tuned 200 pipes in about 90 minutes;
> > > >
> > > > What's the range of tuning on an organ like this?
> > > >
> > >
> > > By "the range" do you mean the keyboard compass? Single
manual, 50
> > > notes from C up to d'''. We tuned the 8, 4, 2, and 1 1/3
foot ranks.
> >
> > I meant, how much can you tune/detune each pipe?
>
> I don't know what you mean by "detune" here, for sure (synthesizer
> terminology??), but I assume you're asking about how much each
pipe's
> pitch can be raised or lowered off some central average point.

Yes- I assume the organ-tuner's term for this is simply "tuning",
the same as the synthesist's (detuning usually refers to multiple
oscillators).
>
> On this particular organ, the open 4' flutes tuned by shades could
>be
> adjusted by approximately 1/4 step in either direction: by making
>the
> shade go straighter up or more tightly bent across the opening.
>
> The sleeved open 2' and 1 1/3' have a little bit more range than
>that,
> depending how long their sleeve is.
>
> The stopped 8' flute has about 1/4 step of leeway downward in
>pitch
> (i.e. pulling the stopper up farther), but a huge possible range
upward,
> on the same principle as a slide whistle; depends how much excess
there
> was to the pipe's length to begin with. It can only be pulled out
so
> far, lowering the pitch, before it pops out the end...but it can
pushed
> down into there as far as one can force it to go, raising the
pitch. It
> just has to make a tight enough seal, wherever it is.
>
> As I said before, we did this all by ear, not by measuring any
cents on
> an electronic device.
>
> We did briefly try to measure a few of the 4' flute notes at the
> beginning of the session, but their pitch was fluctuating all over
the
> place while holding a steady note. This is normal. Somebody can
> probably say more about the usual chaos in the wind of a shaded >
>pipe or
> a stopped pipe. The open metal pipes (sleeved) were considerably
steadier.

Thanks, that's very interesting, and 90 minutes seems very quick to
me. By "1/4 step", do you mean a fourth of a diatonic tone of about
9/8, or specifically a 12-tone step?

-Cameron Bobro