Navigate this Product

TU-88: Micro Monitor & Tuner

Triple-Function Monitor/Tuner for Guitar and Bass


Small, cool and feature-packed, BOSS’ new TU-88 is a must-have for guitar and bass players on the go. Available in black or white, it provides needle-accurate tuning, a metronome, and a headphone amp with speaker simulator for monitoring effects, including compact pedals.

  • Three tuning modes (Chromatic, Guitar, Bass), Flat Tuning function and ACCU-PITCH verification with an audible beep
  • Built-in headphone amp lets you tune, jam and play your effects with headphones or direct recording
  • Built-in metronome with selectable rhythmic patterns and volume control
  • MIX IN allows jamming with an external music-playback device (iPod, etc.)

Triple-Function Monitor/Tuner for Guitar and Bass


Tuning Range
E0 (20.6 Hz) - C8 (4,186.0 Hz)
Reference Pitch
A4 (435- 446 Hz)
Tuning Accuracy
± 1 cent
Power Supply
Dry battery 6F22/6LR61 (9 V) type, AC adaptor DC 9V (PSA series; optional)
Current Draw
30 mA
Expected battery life under continuous use (carbon)
Approximately 8 hours
*This figure will vary depending on the actual conditions of use.
Dry battery 6F22 (9 V) type (carbon), Owner’s Manual, Leaflet (“USING THE UNIT SAFELY” and “IMPORTANT NOTES”), Information
Size and Weight ( including battery )
140 mm
5-9/16 inches
80 mm
3-3/16 inches
30 mm
1-3/16 inches
0.2 kg
0 lbs. 7 oz.
*The specifications are subject to change without notice.


If you have questions about operating your BOSS product, please check our Knowledge Base for answers to the most common questions.

You can also contact our Product Support department by phone or email.

In addition, we have a library of Support Documents that you can download and reference. If Support Documents are available for this product, they will be listed below.

Support Documents

BOSS Tuners Catalog 2009
BOSS tuners are beloved by musicians around the world for their reliability, accuracy, and user friendliness. Since 1983, the TU-12 has been an industry standard. Today’s family of BOSS tuners melds the essence of the TU-12 with modern technology in a wide variety of models.
TU-12/TU-88 Brochure
BOSS Product Catalog 2012
BOSS Product Catalog 2011