You can shorten the effective vibrating length of the reed by sliding a capo-like bar, starting at the base of the reed and sliding forward toward the tip. I have seen one-reed pitch pipes that actually work this way. However, stuffing all those tuning slides into a harmonica, and then running control rods out to the outside so that you don't have to open the harp to tune them, but doing it without compromising airtightness, sounds impractical. Also, reed tone and response might suffer.
Besides, all harmonicas are tunable anyway. Sure, it's more trouble than tuning a guitar, but it's way less trouble than tuning a piano.
Winslow zzzzz
----- Original Message ----- From: Ronnie Schreiber<autothreads@xxxxxxxxxxxxx> To: "harp-l@xxxxxxxxxx"<harp-l@xxxxxxxxxx> Cc: Sent: Tuesday, November 25, 2014 12:41 AM Subject: [Harp-L] Tunable harmonica
On the Shark Tank thread mention was made of a hypothetical tunable harmonica. The only way I can see doing that is by changing the effective length of the reeds. Will a reed that's shorter than its slot in the reedplate still operate normally?