Boss TU-3 Chromatic Tuner Pedal Review

96 out of 100. Incorporating 4950+ ratings and reviews.


  • Tuning Accuracy: ±1 cent
  • Tuning Range: C0 (16.35Hz)–C8 (4186Hz)
  • Reference Pitch: A4=436 ti 445 Hz (1 Hz step)
  • Tuning Modes: Chromatic and Guitar/Bass mode (tune by string number, with support for 7-string guitars and 6-string basses)
  • Display: 21-segment LED meter with brightness control
  • Bypass: Buffered
  • Power Supply: DC 9 V: Dry battery 6F22 (9 V) type (carbon), Dry battery 6LR61 (9 V) type (alkaline), AC Adaptor (PSA series: optional) – can supply power for up to 7 Boss pedals
  • Battery Life: Not specified
  • Dimensions: 2-7/8″ (73 mm) x 5-1/8″ (129 mm) x 2-3/8″ (59 mm)
  • Weight: 14 oz (390 g)

Boss TU-3: Rugged and Reliable Utility

There are special kinds of pedals that don’t produce an effect yet are indispensable tools in our pedalboard arsenal.

This is where the TU-3 fits in – combining a power supply with a highly accurate tuner in a form factor that many know, trust and love. The TU-3 is successor to the highly popular TU-2 with improvements where they matter most such as in the LED light brightness and in tuning accuracy down to plus/minus a cent.

So far this has been a reliable companion on stage and in the studio.

Personal Experience

Having recently acquired some second hand pedals as a set, I was delighted to see included the Boss TU-3. Tuning is a no-nonsense affair, when in tune the bright LED indicators give you a clear signal then it’s on to the next string.

I know there are newer tuners out in the market today… some very highly rated like the Polytune that can sense the pitch of all your strings simultaneously. Call me a wisecrack but I never saw the need to tune all my strings at the same time because I can only turn one tuning peg at a time!

When activated in its default setting, it mutes your guitar signal which I instinctively do in between songs to block out annoying electrical noise and the occasional accidental strum. I find myself tuning often in a single set and correcting strings that were knocked off tune due to bends or aggressive strumming.

I don’t use alternate tunings at the moment so the lack of DADGAD tuning or other exotic tunings baked into the pedal doesn’t bother me much, but I could see someone opting for a tuner with this feature.

As a power supply, the optional PCS-20A Parallel Daisy Chain DC Cord (Link to Amazon) allows you to power up to 7 other pedals when using the tuner with the PSA-120S power adapter (Link to Amazon). I have experimented with this setup, powering other pedals with the TU-3 via its input and output power with a Mooer 9V daisy chain power supply but I have yet to see the benefit of this configuration as opposed to just powering all my pedals straight from the daisy chain – or at least with the power supply I have that is not the official Boss one.

Boss TU-3 9V Jacks
I’ve got the power

I am delighted by how this pedal works. It fulfills the two things that are important to me in a pedal like this, robustness and intuitiveness – this passes my test with flying colors.

Honestly if I could only bring one pedal to the stage it would be this one.


Alden's Boss TU-3 In Hand
This is my tuner. There are many like it, but this one is mine.

The TU-3 is primarily designed to tune electric guitars (or acoustic guitars with a pickup) and bass. It also supports 7-string guitars, and 5 or 6-string basses.

It also has a chromatic mode, allowing you to hypothetically tune any instrument compatible with a 1/4″ input within its tuning range of C0 (16.35Hz)–C8 (4186Hz).

You can change the brightness of the lights by holding the left button and you scroll through the different modes with the right button.

Audio Routing

  • INPUT – This is where you plug in the instrument,
  • OUTPUT – This is where the sound of your instrument comes out. It is muted when tuning is activated.
  • BYPASS – Use this output to bypass the muting function. You will be able to hear your instrument while you tune from here.

Using both the OUTPUT and BYPASS at the same time you are able to split your audio signal.



  • No alternate tuning options
  • No cons for my personal use


  • Simple to use
  • Durable Boss compact pedal enclosure
  • Clear indicators and accurate tuning

It’s not the sexiest piece of gear but it fulfills an essential role without any drama – and I love that. I give the Boss TU-3 a 98 out of 100!

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