Focal Professional Trio6 ST6 — A Mix Real-World Review

New York, NY (March 20, 2024)—Designed and made in France, the now-redesigned Focal Trio6 ST6 is a beautiful-looking three-way studio monitor and the latest addition to the company’s ST6 range, which includes the Solo6, the 2.5-way Twin6, and the powered Sub12 subwoofer—all released in 2022.

The Trio6 ST6 has an internally braced, black cabinet made from 22 mm (7/8-inch) MDF and comes with dark-red, natural-ash veneered side panels. A single Trio6 monitor measures 53.7H x 29.2L x 36.9D cm and weighs 25 kg, or about 55 pounds.

A carefully designed laminar port minimizes chuffing and noise; it is located on the front of the cabinet just below the 20.3 cm (8-inch) woofer. The woofer uses Focal’s patented, composite W-cone design and has a frequency response down to 35 Hz. Directly above it is a 12.7 cm (5-inch) midrange driver that uses a tuned-mass damper to reduce distortion in the 1 to 3 kHz range. A 2.5 cm (1-inch) inverted-dome tweeter made from Beryllium extends the monitor’s frequency range out to 40 kHz with very little beaming directionality. Mostly used in aerospace applications, Beryllium (Be, atomic number 4) is a strong, lightweight metal. A strong wire mesh is used to protect the tweeter.

STUDIO AND SETUP

I am a freelance engineer/mixer/producer and work in a small room that is approximately 2.89 m (9.5 feet) wide and 5.76 m (18.9 feet) long. The ceiling height is 2.49 m (8.1 feet).

My pair of Trio6 ST6 monitors each sit on a set of four Iso-Acoustics Iso-Puck 76 vibration isolators. The Trio6 and Iso-Pucks sit atop 431 mm (17-inch) square pieces of 19 mm (3/4-inch) thick wood planks on top of Sound Anchor speaker stands (Model ADJ2).

Through years of experience and experimentation with other professional monitors, I’ve found the optimum distance to the L/R side walls that minimizes speaker boundary interference response (SBIR) is about 0.82 m (32 inches). This distance doesn’t compromise stereo width and imaging. The distance from the front wall is 0.68m (27 inches) measured from the center of the Trio6’s rear panel/heatsink.

The monitors are 1.16 m (46 inches) above my hardwood floor. The L/R monitors are 1.16 m apart (46 inches) measured from the center of each woofer, completing the front side of an equilateral triangle, with the optimum listening position located at the third point, out front and in the exact center of the room’s width dimension. Both monitors are vertically oriented and “toed-in,” or angled inward slightly toward the listening position.

Focal recommends that the midrange/tweeter plate be head height, but for my clients and musicians, who typically stand behind me while listening, I have them slightly higher up. The entire midrange/tweeter plate can be rotated in 90-degree increments for horizontal positioning. (Note: I did not test the Trio6 ST6 in horizontal orientation, as I do not have the room on my stands and, in that position, there would not be enough L/R distance from my side walls to allow for it without creating a greater SBIR issue.)

ELECTRONICS AND REAR PANEL

Nearly the entire back metal panel of the Trio6 is used as a heatsink for the three power amplifiers. There are switches for changing the Input sensitivity to either +4 dBu or -10 dBV using the same XLR input connector.

The bass and midrange amplifiers are rated at 100 watts RMS each, running Class-G, while the tweeter’s Class-AB amplifier is rated at 50 watts. There is also an Auto Standby enable/ disable switch on the rear panel. Auto Standby will “wake up” the monitors from power-saving sleep mode (front-panel red LED) as soon as audio input is detected.

I especially liked that there is a four-position rotary switch for the highpass filter knee (-3 dB starting at 150 Hz). Low-frequency modal resonances—extreme peaks and nulls—always present the biggest problems, especially in small rooms. Here there are four choices: flat, 45, 60 and 90 Hz.

There are three more pots to adjust ( 3 dB) three equalizers for the incoming audio signal. A low-frequency shelving equalizer starts at 250 Hz; the midrange EQ is a low Q peaking type (Q=1) with a center frequency of 160 Hz; and the high frequencies are covered with a shelving equalizer starting at 4.5 kHz.

Until I acoustically re-measure my room and/ or add the Sub12 ST6 Subwoofer to make a 2.1 system, for now, I left all these controls in their flat position(s). I certainly like the option to measure my room and carefully adjust these additional controls as required.

DUAL FOCUS MODE

Focus Mode is a feature in the Solo6 ST6, Twin6 ST6 and now the Trio6 ST6 monitor systems. The Trio6 ST6 is unique in that it has a Dual Focus Mode, making it three monitor systems in one cabinet.

Dual Focus Mode offers two different known, “constrained,” frequency ranges for monitoring audio using only highpass filters. These two modes offer a way to check how my music mixes hold up when played on much lower-fidelity systems— smaller speakers or over a streaming service.

Focus Mode keeps the imaging and stereo positioning solid, relative to the fixed listening position. This is unlike when using a second set of monitors that have to be placed (physically) either too wide left and right of your mains for an unrealistic stereo width or positioned too close together for a compromised stereo image and center-channel buildup.

Called Focus 1 + 2, the three-way Trio6 ST6 is a full-range system with a frequency range of 35 Hz to 40 kHz (-3 dB). Focus Mode 1 has a 100 Hz to 15 kHz response and uses only the midrange driver, with a separate 100 Hz highpass filter for a one-way system that also shuts down both the tweeter and woofer.

Focus mode 2 is specified at 80 Hz to 40 kHz and uses the tweeter and the midrange drivers together as a two-way system, but with a different crossover circuit than the three-way system. and it shuts down the woofer. Which Focus Mode is active is indicated by bi-colored, front-panel LEDs located just under the Power LED. Focus Mode 1 lights green, and Focus Mode 2 lights orange. On the back panel of each speaker are 1/4-inch TRS jacks for cables to link any number of Focal monitors and subwoofers (Atmos/immersive systems) together so that they all switch Focus modes at the same time.

For this review, Focal supplied a Boss FS-6 dual-footswitch (the proper model to use) and the necessary cabling—these do not come with your purchase, but footswitch wiring is very simple and controls relays inside of the Trio6 ST cabinet; I built my own switch-box for my desktop.

LISTENING IN THE STUDIO

My studio mix room has extensive acoustic treatment that includes two PSI Audio AVAA C20 Active bass traps sitting on the floor in each front corner, with a stack of conventional bass traps and panels above them going to the ceiling.

There are two, thick, absorptive ceiling clouds above the listening position, large absorption panels on the walls left and right of the listening position, as well as both quadratic residue and poly-cylindrical diffusors on the ceiling and also on the rear wall.

After Focal’s recommended 40-hour “run-in” period, I had the opportunity to use this pair of Trio6 ST6 monitors for about six weeks, now using them every day for both my music mixing and my lengthy Grammy voting process of listening and recording each nominee over the course of about five long days. This worked well as a run-in period to acquaint myself with the Trio6 ST6s, playing all kinds of music genres. I found it easy to develop a good relationship with these monitors and soon felt I could trust them.

From the first time I listened to them, there is no doubt that the Focal Trio6 monitors sound great! They are smooth and accurately reproduce transients and all frequencies in a musically balanced way.

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I admit I was highly skeptical about the utility of the Focus Modes, but I am now using them as part of my regular process when starting new mixes—it is especially useful for music/songs I didn’t record. Focus Mode 1 (green) is much brighter and a little thinner-sounding, and is useful for hearing full mixes at very low volume, as if played on small speakers. Focus Mode 2 (orange) is full-range except for less bass, as you would hear on small speakers. I use it for equalizing, layering and mixing midrange guitars and keyboard instruments, all (temporarily) panned to the center.

I am excited to have these Trio6 ST6 monitors in my studio; they are excellent tools, and with them, I continue to improve my mixing process and achieve better results. I can highly recommend these monitors that look as great as they sound.