The tuning of autoharps, hammered dulcimers, bowed psaltrys, zithers, kanteles, lap harps and many other zither family instruments is adjusted and maintained by square headed, finely threaded steel rods called zither pins. Their threaded sections are driven into the undersized holes of the wooden pinblocks inside the structure of the instrument. Depending on the integerity of the pinblock, the tuning pins can sometimes be very tight with a lot of holding power. This is a positive condition but it warrants some care and a slightly different tuning technique.
To care for the tuning pins, it is necessary to use a quality tuning wrench that engages the square heads of the pins at a variety of positions without excessive wiggle. It must be made of quality materials and shaped so that there is adequate leverage and control for fine tuning. Unfortunately, most of the wrenches we acquire with our instruments are disappointing if not downright hazardous. Most smaller L-wrenches and “clock key” style wrenches with square tips are cast with inferior metals and do not fit solidly on the tuning pins. Since they lack leverage and grip, their tips become stripped and they chew up the tuning pins.
Don’t be tempted to buy or use those types of wrenches. You will have disappointing results and can risk expensive damage to your instrument’s tuning pins. Instead, acquire a “star tipped” wrench. Two types are readily available in music stores and online. One is a “T” type wrench and the other is a longer “L” type that resembles a piano tuning wrench. Both feature hardened alloy metals with a star shaped tip that firmly engages the pins at a variety of angles. They have longer handles that make them easier to control even very tight pins.
Tuning for better stability
Zithers are very much like pianos only smaller. With my experience as a piano technician I have learned that properly “setting” the pins and equalizing string tension results in a more stable, long lasting tuning. The following techniques that I employ tuning pianos also work with zithers.
When turning a pin righty-tighty, two things happen that affect stability. A section of the string is drawn over the bridges and, in a tight block, the tuning pin twists. These forces briefly become part of the string’s and pin’s short term memories. Tiny kinks where the string previously crossed the bridges are drawn ahead and the twist introduced to the pin lingers. As these forces equalize, the string un-kinks and the pin straightens. When they do, the string is no longer in tune.
As a tiny kink in a string slowly relaxes, the pitch goes slightly flat. While changing the pitch of a string by more than a few cents, stretch it by pressing down on the speaking length with a finger or a narrow piece of wood like a popsicle stick. Check the tuning, pluck the string rather hard, and then check the tuning again. This will help ease the kinks, seat the string on the bridge, and stabilize the string tension.
When a pin retains a twist it is called “flagpoling”. The torque of turning it in a tight block actually bends it into a spiral. It takes a little time to relax into its former shape. To minimize this effect I like to use a long handled L-wrench. With its extended handle and wide swing, I can “bump” the pin with a wigglely/jerk that turns the whole length of the pin at once with less twist . I tune the string a few cents sharp and then wiggle it back to the target pitch which helps the pin return to its straight shape.