Boasting an incredibly solid build and powerful DSP, the OSD Black Series offers excellent clarity and output, writes Stephen Dawson.

OSD seems like an odd name for a speaker company. The founder’s initials perhaps? Actually, it apparently stands for Optimal Speaker Design. It was established in the United States in the early 2000s. We all know the meaning of LCR, though. Since I was provided a 3.1 system for review, I simply kept my regular surrounds and overheads to create a 3.2.1.2 system.

What are they

The three front speakers are all LCRs, albeit of a slightly different design. They can all be placed vertically or horizontally. In fact, under the magnetically secured grilles the placement of the logo suggests horizontal placement. The review system consisted of a pair of OSD Black T69LCR speakers, one OSD Black T65LCR speaker and one OSD Black Trevoce10DSP subwoofer.

I set up the 69s as front left and right, vertically orientated, and the 65 as a centre channel, placed horizontally.

Both speakers are installation speakers, meant for mounting in wall cavities. But not too inconspicuously. Their cloth grilles are black and certainly don’t look like they’d take kindly to a coat of paint. I imagine that the cloth could be replaced professionally should that be needed in a particular environment. The speakers come in very solid enclosures.

The required space behind the front of the wall is 104mm. There are no connections or protrusions at the back to get in the way. The spring-loaded connectors are at one end of each enclosure and can accommodate large gauge cables. Swing-out clamps in the enclosure can be used to secure the speakers to wall panels.

At first glance it looks as though the 25mm titanium dome tweeter of the T69LCR speaker is surrounded by 165mm woofers, two on each side. But it turns out that this is a three-way speaker. The 165mm driver just on the far side of the tweeter from the terminals is a midrange driver, while the other three are woofers. All four of these drivers use carbon fibre for their cones. OSD says that each driver is in its own internal enclosure. The entire enclosure is sealed. And, as I said, is very solidly built.

Indeed, the T69LCR speakers are over 1.1 metres long and more than a third of a metre wide. And each weighs 18.2 kilograms, which is way up there for speakers of this kind. I’d suggest a solid noggin be placed between the studs for the speaker to rest upon. The speakers would best be installed with the tweeter at ear level and the midrange slightly underneath, so that will leave the wiring at the top.

OSD Black says that their sensitivity is 91dB. That’s quite high for a sealed design, but later when I was using it, it felt about right for a given setting of the volume level control. It also rates them at 100 watts “RMS” power handling, by which I take it to mean “continuous”. Despite all the woofers, the modest internal volume of the enclosure restricts bass performance, with OSD Black variously putting the bottom end at 80 hertz (website) or 100 hertz (printed guide). Either way, it is clear that these speakers are expected to be used with a subwoofer.

The T65LCR speaker is kind of similar. It’s shorter at 721mm and although the enclosure is roughly the same width, the grille is a little narrower. It shares a similarly solid build, weighing just over 13 kilograms.

This speaker employs the same 25mm titanium dome tweeter and two of the 165mm carbon fibre bass drivers. It also is three-way, with a 102mm paper cone midrange next to the tweeter. OSD Black puts its sensitivity only slightly lower at 90dB, its power handling at 60 watts “RMS” and its low frequency extension to 100 hertz (website) or 85 hertz (printed guide).

The OSD Black Trevoce10DSP subwoofer is an interesting unit. It is not for putting in a wall, but is a fairly conventional standalone unit. It’s around 370mm by 370mm by 320mm and, again, solidly built at more than 14 kilograms.

It packs a 254mm forward-firing driver, with a 254mm passive radiator on each side. If you’re planning on tucking it into a corner, it should be angled at 45 degrees to allow the maximum amount of breathing room for the radiators. Inside is a digital amplifier providing up to 500 watts. OSD Black rates its frequency response at 20 to 160 hertz.

Nothing too unusual there. What is unusual is indicated by that “DSP” suffix to the model number. There’s also a non-DSP model. But this subwoofer can do all manner of processing to the incoming signal to help overcome room problems. There are delay features, a 25-point parametric equaliser and various other adjustments. The adjustments are made by means of an app – iOS or Android – and a Bluetooth connection with your phone.

You can install the free iWoofer app on your smart device. If you have an iOS device, you can instead install the iWoofer Pro app. That one costs you a few bucks, but it adds an automated calibration routine. This version isn’t available for Android, presumably because their inbuilt microphones are far less predictable.

The app is immensely powerful. Or I should say the DSP is immensely powerful, since the app is merely the controller. Even five minutes with my iPad and the auto calibration system had the bass response smoothed out considerably. This only works above approximately 40 hertz. Below that, frequency changes can be made manually. I guess they only trust the iPhone/iPad microphone so far.

Listening

I did all my listening running the system from a Denon AVR-X3500H home theatre receiver – 7 x 105 watts – having calibrated first the subwoofer using its system. Then…what? I could have just run the Denon’s calibration after that, but that did not seem optimal. Why would you want two sets of DSP having a go at tuning up the subwoofer? The Denon uses the Audyssey MultEQ XT32 system for calibration and EQ. This does adjust the subwoofer, but Audyssey have also stated that EQ settings are retained even if you do manual changes to the crossover afterwards.

So first, I factory reset the Denon to start with a clean slate. Then I ran Audyssey in the usual way, but without having the subwoofer connected. After that, I plugged in the subwoofer, manually changed all the speaker crossovers to 80 hertz (100 hertz for the ceiling speakers) and manually balanced the level of the subwoofer. Which meant only the inbuilt DSP massaging the performance of the sub.

I ran through my usual collection of movie clips and the results were extremely solid. Especially when playing back at not too far short of cinema levels. The 105 watts of the Denon was more than adequate for my room (6.5 by 5 by 2.4 metres), with seemingly more on tap.

Of course, I did not have the front speakers actually set into my wall. They were merely pressed up against it. Closer in would have helped their bass a little, but they seemed fine. The subwoofer was easily able to carry the load and never once even hinted at running out of steam.

The subwoofer exhibited plenty of slam, but didn’t seem to extend very far, if at all, into the infrasonic reaches. Not surprising, since it’s only specified down to 20 hertz. Certainly, the really deep stuff on the animated feature Titan A.E. didn’t energise the room to the same extent as my regular 15-incher.

In fact, I think this subwoofer might have been engineered to perform similar to cinema subs. They typically only reach down to 30 hertz – the deeper you go, the harder it is to avoid spill over into neighbouring screens.

When I’d finished and before packing up the gear to return, I factory reset the subwoofer and then conducted a quick measurement up close. It delivered a slightly peaky output across its range of operation, from 30 hertz to beyond 180 hertz.

But below 30 hertz simply plummeted – down by 18dB or more at 20 hertz – so steeply that it was surely a design decision.

So, probably not the best choice for those who want extreme bass reach, but excellent for those who want plenty of clean, fast slam in their bass.

That came through with music. I played through the Steve Wilson surround remix of the classic Yes album Fragile at a very high level. The performance was superb. Sound steering was precise and there was a surprising amount of detail. The drum kit, and especially the kick, seemed limitless in power.

Conclusion

The OSD Black Series LCR speakers are excellent in terms of clarity and output levels, and should be fairly easy to install. You will require a subwoofer, and the OSD Black Trevoce10DSP subwoofer was an excellent match.