Boss TU-2 Tuner

History:

As difficult as it is to imagine today, tuning a guitar has changed radically even in recent years. The earliest tuners were tuning forks, invented in the early 1700s. Musicians would have to tap the fork and tune their instrument to it by ear.

It took all the way until 1936 to standardize the A note above middle C as being 440Hz. That same year the Conn company invented the strobe tuner. A strobe tuner has a spinning wheel with a pattern printed on it, and the wheel is lit from behind by a strobe light that flashes at the frequency of whatever pitch it hears (like a guitar string). The flashing is faster than the human eye can see, and it creates the optical illusion that the pattern on the wheel is spinning slowly to the left if the note is flat, and spinning slowly to the right if the note is sharp. When the pattern on the wheel appears to stand still, the note is in tune. The pitch the musician wants to tune to is chosen with a dial on the front, and the dial causes the wheel to spin at different specific speeds to make the illusion work. Strobe tuners can be extremely accurate, but the early strobe tuners made by Conn starting in the 1930s and Peterson starting in the 1960s were fairly large, expensive, and fragile. Most bands with electric guitars would tune by ear to each other’s instruments.

In 1964, Peterson invented the first battery powered, portable instrument tuner with the Model 70. It played a tone chosen from a dial on the front, and the musician would tune their instrument to the sound of the tone. There was no visual indicator of whether the note was in tune or not.

In 1975 Korg released the WT-10, which was the first visual, portable, battery powered instrument tuner. It was a needle tuner, meaning a needle would move to the left if the note was flat and to the right if the note was sharp. When the needle stayed “straight up” in the middle, the note was in tune. Within a few years Boss released the TU-120, a portable, battery powered LED strobe tuner that also had a tone generator.

In the 1980s, digital tuners started to be produced by more companies. In 1983 Boss released the TU-12, a chromatic handheld, battery powered needle tuner. Before this, musicians had to select which pitch they wanted to tune to before tuning. The TU-12 automatically displayed how far off the note was from the nearest chromatic pitch (A, A#, B, C, etc.). Peterson kept making new kinds of strobe tuners, Korg kept making handheld tuners and ventured into rackmount tuners along with Sabine and some other companies, but the Boss TU-12 stayed as the industry standard through the ’90s.

Around 1995 Boss developed the pedal tuner. The idea was to take a standard Boss compact pedal enclosure and put a tuner inside of it that activated when the footswitch was pressed (as well as muting the signal so the process of tuning isn’t heard throught the amp). Boss sat on this idea for 3 years, not having confidence in the market for such a device. In 1998, they finally released their pedal tuner: the Boss TU-2. It became a huge hit, and was a must-have pedal for beginners and professionals alike. The DOD FX12 “Tuna”, the Arion HU-8500 Stage Tuner, and the Danelectro Dan-O-Matic pedal tuner all predated the Boss TU-2, but they all had design flaws that the TU-2 improved upon. The DOD pedals notoriously had awkward footswitches, and both the DOD and Arion tuners were guitar/bass only (not chromatic). The Danelectro’s display was very small, dim, and hard to read. The TU-2 had none of these problems.

The Boss TU-2 had almost every feature offered in a tuner up to that point. It auto-sensed the note being tuned. It had chromatic mode as well as guitar/bass mode, and in guitar/bass mode the pedal could be set to standard, half step down, or full step down tuning. It could be run off a 9V DC power cable or a battery. It also had a 9V DC power out jack so another pedal could be powered from the TU-2. The tuning reference pitch could be selected as anything from 438-445Hz. And finally, the TU-2 could operate as a needle style tuner (trying to get the lit LED to the middle) or as a strobe style tuner (trying to stop the LEDs from moving).

From its introduction in 1998 until it was discontinued in 2010, the TU-2 was not only the most popular tuner pedal, it was the highest selling pedal overall. Throughout the ’00s other competitors entered the pedal tuner market. Peterson created virtual strobe tuners that were more precise than the TU-2 (+-0.1 cents precision vs the TU-2’s +-3 cents precision), though the Peterson pedals were less foolproof to use. Peterson won over many steel players with its tempered tuning offsets, but did not dethrone the TU-2 overall. The Sonic Research Turbo Tuner pedal (released in 2008) was an extremely high quality tuner, but the small company didn’t put a dent in Boss’ market share. Other companies put out pedal tuners to varying degrees of success, but throughout the life of the TU-2 it remained king. In 2009 Boss introduced the next generation TU-3, with more LEDs for more precise tuning and a few other minor features added. The following year, in 2010, the TU-2 was discontinued.

While the TU-3 was an improvement to the TU-2, in 2010 the competition stepped up their game. TC Electronic released the PolyTune; the first polyphonic tuner pedal. It could register all 6 strings at once for even faster tuning. The original PolyTune wasn’t perfect, but the flashy hook of having polyphonic tuning caused many guitarists to switch to the PolyTune, and it grew even more popular with the improved PolyTune2 and Mini. Throughout the 2010s, at least among professional boards, the tuner market was split between the PolyTune family, the Peterson family, the Turbo Tuner family, and some holdouts still using their TU-2s. A smaller number of boards have a D’Addario, Korg, or GoGo tuner pedal. Another wrinkle thrown into the tuner game was the popularization of digital multi-effect pedals like the Line 6 HX Stomp, which has its own onboard tuner, making a standalone tuner optional whereas previously it was necessary. Companies like Shure also started to make pedalboard-mounted wireless receivers with built-in tuners, eliminating the need for a dedicated tuner from live boards. As of 2021 most players still prefer a standalone tuner on the board rather than rely on a tuner built into something else.

Use:

JT used the Boss TU-2 starting between 1998 (its release) and 2004 (earliest photo on the internet of his session rig). A 2009 YouTube video shows JT using his Boss TU-2 in chromatic mode + streaming mode (emulating a strobe tuner’s movement). In the full DVD that the YouTube promo is advertising, JT tunes the open strings and sometimes the 12th fret harmonic of the low E. His use of the TU-2 and tuning only the open strings and 12th fret harmonics implies that no tuning offsets or tempered tunings were used. Just traditional straight up tuning to 440.

The TU-2 was placed in the Tuner Out of the Ernie Ball Volume Pedal and left on throughout the session. JT would tune frequently between songs, and sometimes in the middle of the song when not playing. Since the TU-2 was connected to the tuner out jack of the volume pedal, JT could put the volume pedal in heel position so no sound would get to his amp and he could still tune his guitar without making noise. His subsequent pedal boards had the tuners in the tuner out of the volume pedal, or in the case of his Trailer Trash board, in the tuner out of the loop switcher.

Specs:

The Boss TU-2 manual can be found by clicking here.

5.08″ long
2.87″ wide
2.32″ tall