Triple Threat

OSD AUDIO

is a maker of many audiorelated things, its extensive product line covering most bases for custom residential and commercial installations. But the company also has a fair number of consumer offerings, including a sizeable range of subwoofers. Last year I reviewed its Nero Tubebass 10, a cylinder-shaped model that provided a decent wallop of bass given its compact size and $179 price. Now, for this review I’m stepping up to the Trevoce 12 EQ DSP, a flagship subwoofer from the company’s swanky Black Series that still tops out at a reasonable $600. (By the time you're reading this, a 15-inch model with a $799 price should be available.)

The Trevoce 12 EQ DSP combines a 12-inch front-facing active driver with a pair of 12-inch side-facing passive radiators. (Other models are available with

10- and 8-inch driver/passive radiator configurations.) OSD Audio specs “power handling” at 800 watts and frequency response as extending down to 18Hz +/-3db. Impressive, but the main attraction of Trevoce models is the builtin DSP, which can be controlled using the third-party iwoofer ios/android app (free for the base version and $10 for a Pro one that adds auto room EQ and other features like an SPL meter).

According to OSD Audio, as of July 2021 the Trevoce 12 ships with a native DSP EQ curve that’s responsible for extending bass to below 20Hz. (An earlier version of the sub delivered around 6db higher SPL, but had reduced low-frequency extension.) A notable feature of Dsp/app control on Trevoce series subs is the ability to shape frequency response using 25-band parametric equalization, a process that can be carried out via your own golden ears or, even better, some type of speaker measurement software.

OSD Audio’s sub is a 15-inch cube with gently rounded edges and a black

“synthetic-leather” finish. Substantial rubber cone feet isolate the Trevoce 12 from vibration, and its front-facing active driver is covered by a removable black mesh grille. The sub’s side-mounted passive radiators are exposed, with the pattern on the woven glass fiber surface lending it a high-tech look.

Connections on the Trevoce 12’s rear-panel include speaker-level inputs and outputs, a stereo RCA low-level input, and an RCA LFE input. There are continuous dial adjustments for volume and crossover frequency (40Hz-200hz), and a 0-180 degrees phase switch. Additional switches are used to enable the sub’s DSP control when using the iwoofer app for adjustments and to set the power mode (Auto, On, Off). While it’s nice to have that last option offered, I noted that the subwoofer remained On in Auto mode even when there was no signal being sent to it, with the power LED indicator remaining permanently blue. (The same LED was also very bright and a bit distracting in the dark.)

SETUP

I listened to the Trevoce 12 in two separate systems. The first was in the front left corner of my 16 x 9 x 20-foot (W x H x D) living/music room paired with Goldenear Technology BRX bookshelf speakers. Next, I moved it to my 12 x 9 x 16-foot home theater room to serve as the .1-channel in a 5.1.2 Atmos configuration using Polk Audio Reserve speakers driven by a Marantz SR6014 A/ V receiver, with the sub positioned along the front wall between the right front tower and center channel speaker. Both disc playback and Roon were used for music sources in both systems (via an Oppo UDP-203 player).

While it was good to have a set of physical adjustments on the Trevoce 12 itself, most listeners are likely to use the

OSD Audio's Dsp-controlled subwoofer packs a 12-inch woofer with a pair of same-size passive radiators in a compact 15-inch cube. iwoofer app to dial in settings, as I did. After connecting via Bluetooth, the app shows a UUID identifier for the device that you can then rename (Trevoce

12-1, Trevoce-12-2, etc.). You are also prompted to import the sub’s current DSP settings— basically, the positions of the Trevoce 12’s hardware dials and switches. From here, things get less user-friendly, though OSD Audio’s manual does a decent job explaining the app’s various options.

The main adjustments I used for setup were all in the app’s X- Over menu. This allows you to set both the high- and low-pass filters (20Hz-500hz) and the filter order (12/24/48db octave) by double-tapping a curve on a graph and sliding your finger left/right or up/down. The process isn’t exactly intuitive, but it works once you get used to it. Parametric EQ adjustments (up to 25 bands) can also be made here by hitting “+” and sliding the graphic indicator to the specific frequency you want to adjust. Once that’s done, you slide up/down to set gain (db) and pinch to zoom in/zoom

"Dsp/app control on Trevoce subs lets you shape frequency response using 25band EQ."

out for Q factor (EQ bandwidth) control. After you’ve dialed in your adjustments, all settings can be named and saved as a preset (a minimum of six are available) for easy recall in the app’s main menu.

Another iwoofer feature extensively detailed in the manual is the Room Correction/auto EQ functions provided in the app’s

Pro version. However, an OSD Audio rep I spoke with said “if you are using your internal cell-phone mic [as you would when using an ios/android app like iwoofer], you cannot get accurate results below 50Hz,” citing that as a key limitation. So, rather than deal with inaccurate results, I instead used the free REW (Room EQ Wizard) software running on my Mac computer, along with a calibrated microphone from Dayton Audio, to measure the sub’s output from the listening position in both rooms. This allowed me to properly set the EQ to compensate for measured room modes in both spaces, as well as extend the sub’s response down to the 20Hz region. Using REW also helped me determine the best crossover settings for both setups (60Hz and 12db/octave for the Goldenear speakers, 80Hz and 24db/octave for the Polk Audio rig).

PERFORMANCE

Starting out in the music room, I first streamed Steven Wilson’s “King Ghost” from his album The Future Bites (24-bit/96khz FLAC, Qobuz). The swells of bass in this song were rendered in a clean and very dynamic manner. There was also a distinct fullness to the low end that added warmth to the overall sound and provided a solid foundation for the electronic drums, synths, and ethereal vocals to float upon. Comparing the sub’s performance with EQ switched off, the bass came across notably muddier, and dynamics were muted as well.

The same qualities I noted in the Wilson track carried over when I next spun “Valley” from The Orb’s 1995 album Orbus Terrarum on CD. This electronic track features truly deep, subsonic bass, and I was impressed with how much of it I was hearing with the Trevoce 12 in my setup. The cascading rise and fall of the synthesized bass line had a clean quality, while the occasional low slam of percussive elements was conveyed with impressive power and tactile impact. I was also able to push the volume to near-uncomfortable levels and not experience loss of clarity—the sub tracked the loudness increase in an easy, agile manner.

Moving on to something more traditional, I played “The Price of Love” (24/96 FLAC, Qobuz) an Everly Brothers cover from the new Alison Krauss/robert Plant album Raise the Roof. This track has a dense production that could sound murky on a sloppily tuned system, but here it had a strong sense of continuity, with the bass and deep, sonorous percussion cleanly balanced against the vocals and acoustic stringed instruments. Raise the Roof is also available in an Atmos mix on Apple Music, and when I played “The Price of Love” and “King Ghost” in the home theater using an Apple TV 4K, the low end on both tracks sounded nuanced and clean, again providing a solid foundation for the more “spatial” and ethereal elements in the mix to lift off from.

Okay, movie time. Watching the antiques warehouse fight scene from John Wick 3 on 4K Blu-ray, the gunhshots, kicks, and punches were conveyed with a solid and very satisfying impact. Also, more subtle (or rather, less explicit) elements in the soundtrack like the thumping of footsteps on the warehouse’s wooden floor were clearly fleshed out and added a dynamic quality to the presentation.

Given what I’d heard so far from the Trevoce 12, I wasn’t surprised when I cued up the scene from Christopher Nolan’s Tenet where a plane gets hijacked and smashed into a hangar (to create a diversion) and heard the massive impact I expect. Rumbling elements in the soundtrack were conveyed without bloat. Ludwig Göransson’s droning, bass-heavy score was also rendered in a dynamic manner that created extreme tension—the composer’s intent, no doubt.

CONCLUSION

While there are other 12-inch subwoofers offering DSP and app-based control in its price range, the Trevoce 12’s neat looks, compact form, and powerful, yet nuanced performance make it a worthy competitor. The free iwoofer control app can initially cause some frustration, but once you learn how to walk the walk, it’s mostly easy to use, and the extensive range of presets it allows will be of keen interest to bass tweakers. I honestly wasn’t sure what to expect from the Trevoce

12, but the proof is in the listening, and I ended up very impressed with what I was hearing.