HarpTech

THE HARP COLUMN March/April 1997

Curious about what your technician really does with your harp? Try Regulation 101
- By Mike Lewis

When you regulate harps day in and day out, you can lose sight of the fact that harpists don't just automatically know what it is you're doing or understand all the technical jargon you use to describe what you just did. A few glazed eyes and pointed yawns are enough, however, to get the message across. So for those of you who are totally unfamiliar with what a regulation is and for those who wouldn't mind a refresher, welcome to Regulation 101.
Theoretically speaking,
regulation is the calibration of the harp to the string so that, when the pedals are moved, the pitch is raised a half step.
This half-step rise comes by adjusting the length of the string and the angle that the disc deflects the string, commonly know as
grip (see figures 1 and 2).





So much for theory; now on to real life, or Applied Regulation.
The process of regulating a harp involves three steps:
1. Change pedal wrappings and check overmotion
2. Check grip and string line-up
3. Check intonation

CHANGING THE PEDAL WRAPPINGS
There are several
pedal wrapping systems that run the gamut from leather to piano bushing felt. Whatever material is used, it is important that it will last a long time. (No, you cannot go to the local fabric store and pick up a pretty calico print for "Waldo," your pet Horngacher.)
Overmotion is the amount the natural discs turn as the pedal is moved toward the sharp position. Stated another way: in most situations, the natural discs will continue to move even as you move the pedal past the natural position and into sharp. Think of overmotion as motion that is over the amount required to do the job. The amount of overmotion a regulator sets will vary from harp to harp and from harpist to harpist. What is "right" depends on the harpist's goals and the limitations of the particular instrument. By the way, harp techies call the place where the naturals stop moving (en route to sharp) the hump, because depending on the harp and the way the harp is set up, you can get the sensation of going over a hump on your way to sharp. If you drive a car with a manual transmission and are used to changing gears, you know what I'm talking about.

CHECKING GRIP AND STRING LINE-UP
While tuning to a C-flat major scale at
fff (triple forte) with the pedals in the flat position, the technician listens for the string hitting the disc pins and adjusts the string line-up accordingly. She repeats the process with the pedals in the natural and sharp position, but without the tuning part, listening for the string either lifting off of the disc pin or hitting the sharp disc pin. This is "checking for grip"; if the string lifts off the disc pin, you need more grip to hold it in place. You can also watch the string on the disc pin to see if it's moving around. The advanced method that techies use is to rotate the double pin discs slightly counter-clockwise with a screwdriver and see if the disc breaks free. This not only enables us to check the grip, it also ensures that the disc and the set screw are firmly locked together and won't break loose.

CHECKING INTONATION
Calibration, or checking intonation, is done by tuning in flat and then checking the natural and sharp pitches. In a technician's eyes, there are three sections of a harp for intonation calibration purposes. Each section is defined by either the string nut or the disc system that is in use, and each presents different challenges for regulation. Let's start at the top and work our way down (see figure 3)



Section 1: Single pin discs in natural with adjustable string nuts (the top end of the harp).

Section 2: Double pin discs in natural with adjustable string nuts (the mid-range).

Section 3: Stationary string nuts (the bass).

Each section has its own rules, mysteries, and frustrations. But there is no magic; just length, tension, mass, and elasticity factors. As a technician, I work with length and tension. You can do little to control the mass and elasticity factors, except for changing the string or harp design. But, as we really don't want to go there right now, I'll save those two for another day and another course.

THE HARP COLUMN March/April 1997