Pricing and availability

We compare 600+ stores and found this item at 7 stores. Prices updated .

Sweetwater
4.5 (77)
$53.99 $39.99 $14.00 · All time low
Guitar Center
5.0 (64)
$39.99
Amazon
4.6 (435)
$39.99 New
$34.19 Used (Like New)
Reverb
5.0 (19)
$7.99 New
$12.51 Used
Musician's Friend
4.0 (25)
$39.99
B&H
4.4 (14)
$39.99

Price History

Based on price data from 5 merchants for "Boss PSA-120S Power Supply 9V AC Adapter". Prices shown reflect NEW condition. Tracking began Apr 2, 2026.

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Description

Power your gig with confidence using the Boss PSA-120S Power Supply 9V AC Adapter, an essential component for any musician's pedalboard. Designed to convert AC wall current into a stable 9V DC output, this adapter is perfect for powering BOSS pedals and a variety of other devices, from metronomes to tuners. Its rugged construction ensures durability for years of performance, while the low-noise design maintains the integrity of your sound.

With a generous 10-foot cable, the PSA-120S gives you the freedom to arrange your gear without being tethered to an outlet. The thoughtful wall-wart design prevents obstruction of adjacent power sockets, making it a practical choice for cramped stage setups or busy studios. An LED indicator provides a quick visual cue for the on/off status, ensuring you’re always in control.

Whether you're a guitarist, bassist, or keyboardist, the PSA-120S is your reliable partner in maintaining seamless performance and avoiding the hassle of constantly replacing batteries. Power your creativity, one pedal at a time.

Key Features:

  • Converts AC wall current to 9V DC
  • Designed for BOSS pedals, compatible with digital circuitry
  • 500mA output for multiple pedal power
  • 10-foot power cable for extended reach
  • LED indicator for easy on/off status check
  • Compact design avoids covering adjacent power outlets

Product specs

Type Roland/BOSS Power Adapter
Input Voltage Range 100-240V AC, 50-60Hz
Output Voltage 9V DC
Output Amps 500mA
Polarity Sleeve: Positive, Tip/Center: Negative
Compatibility Roland/BOSS devices

FAQs

Is the Boss PSA-120S Power Supply compatible with all BOSS pedals?

Yes, the Boss PSA-120S Power Supply is specifically designed to work with all BOSS pedals, ensuring optimal performance and safety.

Can the Boss PSA-120S Power Supply be used internationally?

Yes, the Boss PSA-120S has an input voltage range of 100-240V AC, making it suitable for use in various countries with different voltage standards.

What is the output current of the Boss PSA-120S Power Supply?

The Boss PSA-120S Power Supply provides an output current of 500mA, which is sufficient to power multiple pedals when used with a daisy chain cable.

What is the polarity of the Boss PSA-120S Power Supply?

The Boss PSA-120S Power Supply has a negative center pin polarity, which is standard for most BOSS and Roland devices.

Can the Boss PSA-120S Power Supply be used with non-BOSS pedals?

While primarily designed for BOSS pedals, the PSA-120S can be used with other pedals that require a 9V DC power supply with negative center pin polarity and do not exceed 500mA. Always check the pedal's specifications to ensure compatibility.

Reviews

PROS

  • Specifically designed for Boss pedals, ensuring compatibility

  • Quiet operation, no 60 cycle hum even with distortion

  • Capable of powering multiple pedals simultaneously with optional daisy-chain

  • Versatile, works with both 1980s synthesizers and modern pedals

  • Reliable, with no reported issues of feedback or malfunction

  • Simple, efficient design providing clean power

CONS

  • May be incompatible with certain systems, leading to potential use issues

Owner Insights

We analyzed real musician discussions from forums and Reddit to find what players love, question, and tweak about Boss PSA-120S Power Supply 9V AC Adapter.

Software and compatibility

  • It's crucial to use a center negative adapter for Boss pedals to avoid compatibility issues, as one user discovered with a non-Boss power supply.

    Source

Setup and maintenance

  • Using a daisy chain power supply setup can effectively power multiple Boss pedals without issues over long periods, even up to three years.

    Source
  • Users found that the PSA-120S adapter reads 10V without load and is louder than batteries, indicating possible variations in output when not under full load.

    Source
  • Some older Boss pedals may require a different 9V adapter or even 12V power; research specific pedal requirements to avoid damage.

    Source
  • Incorrect polarity from generic adapters can fry pedals, evidenced by a user whose pedal's resistor charred due to wrong polarity connections.

    Source

User experience

  • Owners report that Boss pedals function well with generic 9V adapters, indicating no significant difference in performance compared to the official Boss PSA adapter.

    Source
  • Despite their higher cost, Boss power adapters are praised for longevity, with some users still using theirs after 20 years.

    Source

Features and functionality

  • The PSA-120S adapter is 9V with 0.5A, providing 4.5W, which is less than the Katana Mini's 7W rated power but may still function effectively at lower volumes.

    Source
  • A significant difference in fit can occur with non-Boss adapters; generic cords might not lock into the pedal input securely.

    Source

Use cases and applications

  • Adding a switch jack and connecting an external speaker (4 ohm and up, like an 8 ohm 8-inch) can double the volume of the Katana Mini.

    Source

Comparisons

  • The PSB-1U adapter supports up to 2A (18W), making it more suitable for devices with higher power demands compared to the PSA-120S, which maxes at 0.5A (4.5W).

    Source
  • One popular brand of generic adapters reportedly caused damage to Boss pedals, leading to numerous support calls, highlighting the importance of using recommended adapters.

    Source

4.5 out of 5

Based on 1 Review and 6 Ratings

5 star
4 star
3 star
2 star
1 star
rockyoctane

Does the job!

It provides power to my Boss pedals. Made by Boss. Enough said.

Genre Usage

Based on how artists on Equipboard use this gear, it is most commonly found in the following genres.

Used With

Based on how musicians on Equipboard use Boss PSA-120S Power Supply 9V AC Adapter, it is most commonly used with the following gear.

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joaoribeiro

joaoribeiro

Gear IQ 573

joaoribeiro

joaoribeiro

Gear IQ 573

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