Boss TU2 vs Boss TU3 – Classic Boss Tuner Pedals

It’s no secret that Boss are industry leaders when it comes to in-line chromatic tuners. Their TU2 model made its debut in 1998 in an all new stomp box form factor and has been the go-to for amateurs and professional guitarists ever since. Boss have since released the updated TU3, which does raise the question – is it really worth the upgrade?

In this KillerGuitarRigs Guide you’ll learn:

  • What is a chromatic tuner?
  • What are the differences between the TU2 and TU3?

Before we move on to the guide, here are some fast facts about Boss TU2 and TU3 tuners:

  • Both models are based on the classic Boss stomp box design
  • The TU3 benefits from an upgraded display
  • Both the TU2 and TU3 offer cent and streaming modes

What is a Chromatic Tuner?

To understand why the Boss TU series chromatic tuners are so popular, it’s important to understand what it is they do that non-chromatic tuners don’t. A non-chromatic tuner only tunes to standard tuning, EADGBE. These tuners offer some kind of indication to let you know if you’re sharp or flat of the note you’re looking to tune, but not by how much.

On the other hand, chromatic tuners like the Boss TU2 and TU3 indicate where your tuning is in relation to the nearest semitone, meaning you can accurately tune up or down by a semitone. This opens up the entire range of alternate tunings, which makes these tuners very popular with guitarists who record or perform live.

What Are the Differences Between the TU2 and the TU3?

TU-3 Chromatic Tuner Overview

Form Factor

The TU3 launched as a direct replacement in the Boss lineup for the TU2. Boss clearly understood that the form factor was part of what made the original TU2 so popular, and chose not to change the overall form factor at all. Both models are metal stomp boxes finished in white with distinctive orange lettering, and a big, non-slip rubber stomp pad at the bottom. Both have a single input as well as a single output and a bypass.

While some pedal manufacturers automatically assume your pedal will be in a board, and thus leave the base with a bare plastic finish, both the Boss TU2 and TU3 have a rubber bottom pad, which will go a long way toward prevent the pedal from slipping around onstage should you choose to keep it separate from a pedal board.


One of the most noticeable updates on the TU3 was the display. Boss increased the number of LED indicators on the tuning scale to 21 from the original TU2’s 11. This change makes it much easier to see when a note is approaching pitch.

The TU3 display on its standard setting is just a touch brighter than the original TU2, but the TU3 now has controls, allowing the user to adjust brightness as necessary. This is a welcome feature for anyone who plays outdoors in bright sunlight. Both units have their center LED light up green when you are at pitch, but the TU3 ramps this up with red confirmation lights on either side of the green when it’s satisfied that tuning is correct and stable.


Recording artists and studio engineers especially, will appreciate the extra level of accuracy the TU3 provides. The old TU2 is still accurate, registering within +/-3 cents, but the TU3 takes it up a notch and will provide tuning accuracy down to +/-1 cent. It seems like a very small difference and to untrained ears, it may well be imperceptible, but when accuracy matters most, the TU3 will definitely help you to hit that perfect pitch.

Ease of Use

As with the overall form factor and design, Boss didn’t really change anything between the TU2 and the TU3. As far as ease of use goes, both work in an almost identical fashion. Modes are selected through the mode button and display type is changed with the stream/cent button.

In order to keep the form factor the same, Boss opted to include the brightness control within the stream/cent button. It does require that you press and hold in order to adjust, which can cause issues if you have sweaty hands or larger fingers. It does work well enough, but a standalone brightness button would have been a better solution.

Activating either of these tuners when they’re attached to your pedal board couldn’t be easier. Simply stomp once to activate the tuner, this will mute output allowing you to tune in silence. When you’re done, stomp again to reactivate the output.


Both the TU2 and TU3 offer 2 different tuning modes: cent or stream. When in cent mode, the LEDs act like the needle in a standard analog-style tuner, moving left or right of center depending on your guitar’s pitch. When at the desired pitch, the center LED lights up green. In streaming mode, the LEDs race across the display when the pitch is sharp or flat, they slow down as you approach pitch, and the lights stop with the center lighting up green as pitch is reached. Both offer a quick reference for tuning under the pressure of a live performance, which has been one of the most critical factors in the runaway success of this tuner.

For power, the TU2 can run on a dry battery or a 9V AC supply, whereas the TU2 can run on either a 9V carbon zinc or a standard 9V alkaline battery, as well as an 9V AC adapter.

As far as tuning modes go, both the older TU2 and TU3 feature chromatic, chromatic flat, standard guitar, flat guitar, standard bass, and flat bass tuning options, all accessible by cycling through the mode button. With this variety of settings, both options will effectively allow a player to tune to any pitch they want to play in.

Another great feature of both models is the power-out capability. When running a TU2 or TU3 from 9V power, a 7-way cable (purchased separately) will allow you to run power to up to 7 other pedals via your tuner. This is super helpful in cutting down the required number of outlets, especially for those using a homemade pedalboard without a power supply.

Final Thoughts on the Boss TU2 vs the Boss TU3

As evidenced throughout this guide, both pedals are extremely similar. The TU2 was a game changer for its time, and that legacy has carried over into the TU3. The newer TU3 benefits from increased accuracy, thanks to the extra lights in the display and better visibility in bright conditions thanks to the bright mode function. Besides those changes, there’s very little difference, which is why many TU2 users are reluctant to upgrade. If the increased accuracy and brighter display are important to you, the TU3 is definitely worth it. If not, then stick with the TU2 and you’ll still have a great tuner.


  • Simon Morgan

    Simon is an Orlando based musician, but originally hails from Newcastle, England. He started playing bass and guitar in 1998, and played the local scene throughout his teen years before life got in the way. Favorite Genres: Blues, Classic Rock, and he’s not ashamed to admit - Emo