It comes down to: years of practice in building marimbas, fabricating and tuning endless amounts of marimba bars, understanding their physical properties, and using highly accurate pitch-verifying test equipment

Del Roper (Right) testing the pitch of a bar using an old  Stroboconn rotating disc tuner.


Chris a Peterson Model 420 strobe tuner.


The tuning process requires constant checking of the pitch.

Back in 1980, Chris spent many hours with master marimba designer and builder, Del Roper, discussing the detailed points of harmonic tuning.  Without attention to this critical detail, a bar may sound out of tune.  The interest in learning the marimba building craft lead to many construction projects having a multitude of bars of various sizes and ranges. Along the way, there were many tuning jobs.  Most bars were capable of being re-tuned.  But, there were many bars that were so far out of pitch that they couldn't corrected.  Obviously, this required that new bars had to be made from scratch that exactly matched the size and pitch of the unsalvageable bar.  Chris has developed a professional tuning technique and extensive knowledge in (1) how to read, interpret the strobe tuner's images, and (2) most importantly how to apply those readings into correcting a not yet perfectly-pitched bar.  Eventually through diligence, the bar will become perfectly tuned...yes!


Chris's Tuning Station

Mechanical Rotating Disc Strobe Tuners

(Top) Peterson Model 490 Autostrobe

(Bottom) Peterson Model SC 5000-II Strobe Center

Note: The mechanics of the markings on the rotating disc in combination with the flashing light behind the disc create a "wagon wheel effect" or "stroboscopic effect" is an optical illusion in which a spoked wheel appears to rotate differently from its true rotation. The wheel can appear to rotate more slowly than the true rotation, it can appear stationary, or it can appear to rotate in the opposite direction from the true rotation.  The speed of the wheel visually interacted with the film speed rate of 24 frames-per-second will display an instantaneous discernable image.  If the displayed image: moves to the:

Left - the pitch is flat
Right - the pitch is sharp

Stands perfectly still - the pitch is in perfect tune

The wagon-wheel effect (alternatively called stagecoach-wheel effect or stroboscopic effect)