Electronic Tuner - Strobe Tuner

Strobe Tuner

Strobe tuners (the popular term for stroboscopic tuners) are the most accurate type of tuner. There are three types of strobe tuners: The mechanical rotating disk strobe tuner, an LED array strobe in place of the rotating disk, and "virtual strobe" tuners with LCD displays or ones that work on personal computers. A strobe tuner shows the difference between a reference frequency and the musical note. Even the slightest difference between the two will show up as a rotating motion in the strobe display. The accuracy of the tuner is only limited by the internal frequency generator. The strobe tuner detects the pitch either from an TRS input jack or a built-in or external microphone connected to the tuner.

The first strobe tuner dates back to 1936 and was originally made by the Conn company; it was called the Stroboconn and was produced for approximately 40 years. However, these strobes are now mainly collector pieces. They had 12 strobe discs, driven by one motor. The gearing between discs was a very close approximation to the 12th root of two ratio. This tuner had an electrically driven temperature-compensated tuning fork; the electrical output of this fork was amplified to run the motor. The fork had sliding weights, an adjustment knob, and a dial to show the position of the weights. These weights permitted setting it to different reference frequencies (such as A₄ = 435 Hz), although over a relatively narrow range, perhaps a whole tone. When set at A₄ = 440 Hz the tuning fork produced a 55 Hz signal, which drove the four-pole 1650 RPM synchronous motor to which the A disc was mounted. (The other discs were all gear-driven off of this one.) Incoming audio was amplified to feed a long neon tube common to all 12 discs. Wind instrument repair people liked this tuner because it needed no adjustment to show different notes. Anyone who had to move this tuner around was less inclined to like it because of its size and weight: two record-player-sized cases of 30-40 pounds each.

The best known brand in strobe tuner technology is Peterson Tuners who in 1967 marketed their first strobe tuner, the "Model 400". Other companies, such as Sonic Research and Planet Waves, sell affordable LED-based true strobing tuners. There are other tuners with LEDs that have a 'strobe mode' which simulates the appearance of a strobe. However, the accuracy of these tuners when used in strobe mode is no better than when in any other mode, as it uses the same technique as a needle tuner to measure the frequency of the note, and then it sets the speed of the pattern in the LEDs instead of driving a needle.