Sub A125-M

Compact accurate Subwoofer

With its exceptional acoustic design, the A125-M is equally suited to use as a mono subwoofer or LFE in surround sound applications or as a bass extension in a stereo system. Working in perfect unison with all speakers from our range, the A125-M offers all the power with outstanding accuracy.

The Sub A125-M from PSI Audio is a compact reference subwoofer designed to extend your monitoring system with absolute precision rather than exaggerated bass. Engineered with the same fully-analog philosophy and individual calibration as all PSI loudspeakers, it delivers tight, fast, and phase-accurate low frequencies that integrate seamlessly with your main monitors.

Reaching deep into the sub-bass while maintaining exceptional transient response and tonal neutrality, the A125-M allows engineers and producers to make confident decisions about kick, bass, and low-end balance – even in smaller control rooms. Its compact enclosure enables flexible placement, making it an ideal choice for stereo setups, immersive systems, or any studio where space is limited but accuracy is non-negotiable.

In short: the A125-M is built to reveal the truth in the lowest octave – cleanly, precisely, and without compromise.

Main Features

Power

340W

Frequency Range

28Hz – 100Hz

Peak max. SPL@1m

111dB

Typical listening distance

From 1m

100% Analog – No DSP

Flat frequency response

Class G/H Amplifiers

Individually calibrated

5+1 years warranty

Handmade in Switzerland

THE PERFECT LOW END IN YOUR STUDIO

PSI Audio has translated its general approach of unaltered, maximum fidelity reproduction to the bass spectrum, allowing for a riveting experience that will change the way you work. Taking the guesswork out of the bass management, the A125-M grants an accurate representation of what is really going on “down below”. Take control and create a sonic wonderland that reaches throughout the entire spectrum with no insecurities and no need to double-check your work on a different system. Get a subwoofer you can trust.

“The combination of A14-M ​​and A125-M represents an extremely compact full-range interception system with outstanding imaging properties that make listening in the studio a pleasure and promises significantly less exhausting work days.”

Fritz Fey, Studiomagazin

THIS IS NOT A SUBWOOFER

ADD LOW-END WITH THE SUB A125-M

Our low-frequency speakers are designed and calibrated to seamlessly extend the low end of any of our loudspeakers while retaining an overall flat frequency and phase response. It is not so much adding a subwoofer, but more like adding an additional low-frequency way to the speakers. The result is remarkable, especially when reproducing appropriate acoustic instruments. The tight, accurate, perfectly controlled bass unveils every last detail down to 28 Hz.

TECHNICAL DATA

For studio monitors, flatness is fundamental: you don’t want “smiley-face” tuning (e.g. boosted bass and treble) that might sound pleasant but misrepresents the mix. Flat response helps you judge balance, EQ, and spatial placement properly.

Every PSI Audio monitor is individually measured and calibrated in our full-size anechoic chamber.

We fine-tune each unit by hand until it reaches the exact linear frequency response defined in our reference curves.

Your monitor ships with its personal measurement sheet — a unique fingerprint of its precision and a guarantee of uncompromising Swiss-made accuracy.

Recommendation:

Choose A125-M if you want:

• A compact subwoofer for nearfield setups
• Precise bass extension without excessive output
• The perfect partner for smaller PSI monitors
• Flexible stereo or mono sub configurations

Choose A225-M if you want:

• Maximum low-frequency extension
• Higher SPL and headroom
• A sub for large control rooms or mastering suites
• Full-range monitoring performance down to 24 Hz
• An optional LFE input for Dolby Atmos compliance

SUB A125-M – WHO IS IT FOR?

Our low-frequency speakers are designed to perfectly complement our entire speaker range, making the A125-M the perfect addition to our smaller speakers A14-M, A17-M or A21-M.

Even with the larger systems, the A125-M can extend the low end and relax the main speakers, increasing overall performance. Basically, the A125-M is meant to support our monitor speakers when the bass needs more power and precision

HANDMADE IN SWITZERLAND

All our products are handcrafted in Switzerland with passion and attention to detail.

Manufacturing by hand allows to match and adjust components so that tolerances cancel each other out instead of building up, as is often the case in industrial production.

CHOOSE YOUR COLOUR

Choose between Studio Red, Metal Black and Pure White.

Cabinets are manufactured with great care and attention from the choice of the wood all the way through to the paintwork.

WHAT OUR USERS SAY

The Sub A125-M is so precise and perfectly fits my A17-M. I almost have the impression to have a 3-way system.
Ismael Antico – Soundimension

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