Q Acoustics QB12 subwoofer review

What is Q Acoustics Q B12?

The Q B12 is the company’s first subwoofer with a 30cm drive. For distortion-free, muscular and clear bass, Q Acoustics has combined this drive with an ultra-low-distortion 220W Class D amplifier and a 50mm audio coil and a closed, reinforced brace housing.



Available in black or white with a matt or glossy finish. Beneath the grille is a 30cm drive powered by a 220W Texas Instruments TPA3255 Class D amplifier, and a 36mm thick baffle provides maximum rigidity for the drive.

A unique die-cast aluminum heat sink on the back panel cools the amplifier and provides a stable power supply. The stiffener built into the MDF cabinet provides mechanical stability and reduces unwanted vibration and resonance of the device during operation.

There’s also a 0/180 degree phase switch on the back, as well as level and cross changers that facilitate integration with other speakers, although of course various settings are also needed on the AV amplifier for best results.

It weighs 21.5 kg, has an impeccable construction and a closed cabinet. The QB12 is cube-shaped and quite large in size, so it requires relatively large space. This subwoofer works great with the Q Acoustics 3000 series.

Connections and control

q-b12-subwoofer-back panel

The Q Acoustics Q B12 connectors and some controls are located at the rear with recessed placement. The metal cover is fixed with magnets.

In this recessed area you will find a socket for the dual power cord and an on / off switch. There is even a phase switch and another to turn on or auto select, the latter activating Q B12 when it receives a signal.

A couple of RCA line-level inputs are located here, one of which acts as a mono / LFE input. Above the recessed area, there are two rotating discs to control level and crossover.


The Class D digital amplifier has a rated power of 220 W, a maximum power of up to 440 W, and a frequency response of 28-300Hz.

The Q B12 does not have an onboard EQ, but nowadays any decent AV receiver should be able to handle subwoofer integration and alleviate room sound errors.

Setup and operation

The Q Acoustics Q B12 is extremely easy to set up, mainly due to its easy connection and control.

Sound quality

A smaller room was the site of our test, where the subwoofer was paired with Q Acoustics 3020i speakers and a Denon amplifier. Sound-absorbing leather membrane panels and rustic diffusers have been added to the walls of the room to improve acoustics, and membrane corner elements in the corners ensure the right sound.

The Q B12 has proven to be a serious subwoofer, combined with the Q Acoustics 3020i bookshelf speaker pair, the result is a balanced system where the Q B12 supports the other speakers and fills the lower frequencies where necessary. The bass is subtle, very detailed, and dynamic. Due to the closed system, we can expect very sensitive basses.

It provides accurate, detailed and truly dynamic sound.

The Q B12 works subtly and tries to create a cohesive stage instead of blowing our hair with pounding bass.

Sometimes, however, it seemed that it would have been beneficial to have more, lower-end extensions with one touch. Most of the time, the subwoofer did a great job, but occasionally, when really great depths would have been needed, the lack of raw power was obvious. The SVS SB 16 subwoofer performs better in this area.

Why use a subwoofer?

The primary function of the subwoofer is to produce sounds between low frequencies. In order for such a low frequency sound to sound with the required force, a large diaphragm and a large diaphragm deflection are required. For a smaller speaker, the diaphragm needs to move more to produce the same volume. Therefore, the speakers are larger than the other speakers. A larger subwoofer can produce lower frequencies. Although many brands offer 3-way speakers, only subwoofers can radiate pounding, wall-shattering bass. If you like intense bass sounds while listening to music or watching movies, you might want to get a subwoofer as well. It can also be said that with 2 subwoofers, the frequency response and stereo stage image will be even more optimal, and of course the performance will be much higher. In addition, with 2 subwoofers, the sound quality will be ideal for a variety of listening situations. It matters a lot where we place the subwoofer. It doesn’t matter how far you are from the student position and the wall. If possible, do not place it in the immediate vicinity of the wall, it is recommended to keep a distance of 20-30 cm between the wall and the subwoofer.


It’s a high-performance subwoofer that does the job it was designed to do: increase the low-end performance of the brand’s Concept and 3000i series speakers. The Q B12 integrates seamlessly with the 3010i or 3020i speakers, creating a balanced low-frequency sound.

Written by Róbert Polgár