Q Acoustics ‘Q Sub Series’ Subwoofers Overview

British loudspeaker manufacturer Q Acoustics has refreshed its subwoofer line with a new trio of high-performance active subs called the Q SUB Series. The new subwoofer family consists of the 8-inch Q SUB80 ($899), the 10-inch Q SUB100 ($1,049) and the 12-inch Q SUB120 ($1,199). According to Q Acoustics, the Q SUB models are equally at home providing the low end for a multichannel home theater system and bolstering a 2-channel stereo. The subs promise to deliver “powerful, impactful but nuanced and controlled bass” in either scenario. All three models use on-board Digital Signal Processing (DSP) to ensure easy but comprehensive system and room integration, resulting in “class-leading, distortion-free performance,” according to the company. Like all products from the brand, these new subs feature a clean, minimalist industrial design, available in two finishes: Satin Black with a black grille or Satin White with a grey grille. The subs will join the existing slimline 3060S to complete the Q Acoustics subwoofer family.

Q Acoustics Q Sub Series: Design

Under the hood, these subs use a new Q SUB amplifier module, custom-designed by Q Acoustics. This module includes the DSP, the power amp itself, and a custom power supply. The amp features four digital power amplifier stages in a parallel bridge-tied load (PBTL) configuration, reportedly enhancing efficiency and speaker control by reducing output impedance and heat dissipation. On the flagship 12-inch model, this design delivers 300 watts continuous and 600 watts peak power, with THD of less than 0.1% up to 300W. Q Acoustics tells us that the electronics are constantly monitored by an intelligent protection system to ensure that the amplifier and power supply are fully protected from excess temperatures in the unlikely event of malfunction.

The paper cone drivers feature a heavy-duty steel chassis and rubber surround. The Q SUB80 uses a 203mm driver with a 38mm voice coil; the Q SUB100 has a 254mm driver, also with a 38mm voice coil; and the Q SUB120 has a 305mm driver with a larger 50mm voice coil. All models feature an aluminum demodulation ring to reduce the modulation distortion caused by inductance. The drivers are installed in custom sealed-box cabinets, which present a “tighter and more focused bass response” than ported designs, according to Q Acoustics. Sealed subs are also smaller and easier to place in proximity to walls, corners, and furniture. Coupled with the subs’ advanced DSP, the Q SUB cabinet design “allows for very precise tuning to achieve the best acoustic response possible,” according to the company. 

The cabinets themselves are made from 18mm-thick high-density fiberboard, with the front baffle using double-thick 36mm fiberboard for impressive rigidity. Mechanical grounding for the drivers is provided by internal dart bracing, which also contributes to the overall mechanical stability of the design by reducing cabinet “ballooning.” This ensures optimal performance under high internal pressures, according to Q Acoustics. The carefully sealed enclosure prevents air leaks through the amplifier mountings, and even the 15mm MDF grilles have been specially designed to prevent rattling. The cabinets rest on adjustable, locking spikes for floor-leveling, and spike cups are included to protect hard floors.

Q Acoustics Q Sub Series: DSP Features

As Q Acoustics points out, there is an old-school idea that the omni-directional nature of low bass makes subwoofer placement and integration a guaranteed success. Of course, we know that nothing could be further from the truth. In reality, we must take great care to integrate subs with the other speakers, and with the room itself, in order to ensure accuracy and alignment, especially at the crossover point. Placement impacts timing, and phase alignment issues can affect system frequency response. To address these concerns, the Q SUB range uses DSP and fine delay adjustments in addition to the more common phase inversion switch. These tools enable users to “optimize settings for class-leading performance, ensuring seamless integration without needing professional installation,” according to Q Acoustics. 

The Q SUB range also features a low-pass filter with frequency adjustment from 40 Hz to 250 Hz, setting the -6 dB point. This is a wider frequency range than we see on some competing subs, and that should allow the Q SUB models to seamlessly integrate with a wide variety of partnering loudspeakers. The on-board DSP is also used to run a complex algorithm to identify the input signal type — stereo vs. mono — and to analyze the level of the signal. It then automatically adjusts the system gain in order to ensure optimal signal to noise levels and dynamic range, according to Q Acoustics. This reportedly allows the subs to accommodate a wide variety of sound input sources, including stereo preamp outputs and mono feeds from active speakers or home cinema systems. Regardless of the connected source, this source detection feature enhances performance for the best possible sound quality, according to the company.

Q Acoustics Q Sub Series: What We Think

Q Acoustics is one of a handful of British audio manufacturers that seem to consistently deliver great value. Alongside brands like Wharfedale, Cambridge Audio, Rega, and KEF, Q Acoustics makes products that are easy to recommend to audiophiles and regular folks alike. In particular, Q Acoustics speakers tend to offer exceptional build quality at their respective price points, and we expect that these new subs will be no different. All three models of the Q Acoustics Q Sub Series are available now.

More information: Q Acoustics

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