Tuning the Reeds
The speed at which the brass reed tongue vibrates determents the pitch the note produce.
A reed should be removed for tuning. True, you can tune it when it's inside the organ, but it's a
lot easier and safer doing it outside.
The reed can be tuned to its octave, i.e., in other words, if you're tuning Middle C, you can tune it to either
Tenor C or Treble C.
You can also tune it to another reed in a different rank. It's also a good idea to tune the reed to another reed
in a different octave. In other words, a 4ft C should not be tuned to another 4ft C.
It's important to give special care to the reeds, as the metal is often quite brittle and the tongues can easily
A is the vibrating end, or front, and B is the riveted, or back end of the
A jeweler's file is usually the best way to scrape off a small amount of brass from the reed tongue.
If a reed's tone is flat (a lower pitch) you'll need to quicken the vibration speed. To do this, carefully
scrape a very small amount of metal from the reed tongue at point A.
On the other hand, if the reed is sharp (a higher pitch) you'll need to slow the vibrating speed down. To do
this, you carefully scrape a very small amount of metal from the reed
at point B.
Unfortunately, this process is a matter of trial and error. Scrape a small amount of metal from the tongue,
replace it and test its tuning. You may need to scrape off a little more metal, or if you have tuned the reed too
sharp or too flat, you will need to scrape the other end.
For several years now I've been using some software called TuneLab. It was actually designed for piano tuning, but works just fine for pump organs. You
can simply load it to your laptop and you're in business. Robert Scott is the software designer and knows his
stuff. Of course you'll need to pay Robert something before you can download it.