Here at HCC we rather liked REL’s Serie S subwoofers, even if it has involved repeatedly telling sub-editors that there isn’t an ‘s’ on the end of Serie. When the company announced a Super High Output overhaul of the S/5 and S/3 models we had questions. Could they be better than the original? Would the price remain competitive? Might REL find that lost ‘s’? The answer to the last is 'no', but I'm happy to reply in the affirmative to the first two. 

Auditioned here is the REL S/3 SHO. At £1,450 it is around £150 more than the original S/3 yet brings with it a new Next Gen II 400W Class D amplifier, updated driver and revised electronics. The promised result is all the subwoofing goodness of the predecessor S/3 but with more bang for your buck. 

Cosmetically things remain unchanged, save for an SHO legend appearing on the rear. It is the same exquisitely crafted, near cube-shaped cabinet with one of the best piano black finishes on any loudspeaker on the market, irrespective of price. The trim is no less lush, with chunky, REL-engraved brushed aluminium feet, chrome side handles to help move its near 28kg mass about and a bold, chunky ingot of a REL badge in the top. The latter two are also, I'm told, integral components in damping the substantial cabinet, which is over 40cm in all dimensions.

Behind the massive grille with its rear-edge bevel is REL’s 10in, long-throw bass driver. This has a pressed aluminium cone and a rubber roll surround the size of a kids' bike tyre. The cone’s smooth profile and matte aluminium finish are easy on the eye and, if you turn the S/3 turtle, it’s 12in carbon weave passive radiator on the bottom is just as alluring. If you want to run this beast with the grille off, though, the main driver’s gold colour chassis and roughly-cut bolt slots in the rubber surround are a bit of a mark down against an otherwise gorgeous piece of home cinema hardware. 

Proving this model is as much go as it is, er, SHO, it’s 400W amp is coupled with REL’s custom filter network and the option of line-level stereo, line-level LFE/.1 or high-level inputs; the latter via a special cable with a locking Neutrik connector, wired directly to your main amplifier in parallel with the front main loudspeakers. Controls encompass individual line/high-level volume, reversible phase and variable crossover. For an extra £230, you can make the S/3 SHO wireless with REL’s LongBow wireless transmitter.

Carpet bomber

Setting up and positioning the S/3 SHO proved to be remarkable easy, although my rather uneven parquet floor meant some judicious use of a chunk of cardboard to keep things stable. REL does supply traditional carpet-piercing spikes that attache to the feet but recommends you use this woofer without unless you have a shag pile deep enough to lose a hamster in. The reason being that the downward-firing driver requires an air space precisely the height of the feet to perform at its best.

Within 10 seconds of letting rip with a choice cut from John Wick, the S/3 SHO was delivering big LF effects. So much so that as Wick’s car drops into the concrete drain, the resulting explosion blew the grille clean off. Clearly, I hadn’t pushed the lugs fully home when I replaced the grille but it does rather demonstrate what that Super High Output moniker is all about.

Yet sheer grunt and heft is not the S/3’s trump card. What I really noticed, particularly in comparison with my usual 18in-driver Velodyne, was the tautness and impact of its output. Bass effects like gunshots are its forte. The REL’s super-fast transient attack gives these a sense of reality rather than just bludgeoning you with 
a wall of LF noise. It’s a thoroughly addictive experience and certainly goes a long way to deliver on REL’s promise to combine the slam of a 10in sealed box subwoofer with the scale of a 15in driver. I'm not convinced it plumbs the depths to the same extent as a larger model (REL rates it down to 22Hz at -6dB), but it certainly impresses in terms of impact and lack of overhang. 

For typical mid-sized UK cinema/living rooms, REL may have hit on pretty much the perfect-sized sub. Compared directly with my 18-incher, I began to appreciate the S/3 SHO's lightning-fast and evenly-balanced approach to LFE. 

The fire-fight shots around the night-club swimming pool in John Wick proved this point, and the S/3 SHO was equally good romping through some older favourites, like the Atmos-remastered The Fifth Element and space drama Gravity. While the latter film lacks a constant soundtrack of bass, the sound designers use LFE to subtly underpin effects and atmosphere. The REL’s superior tautness and articulation is in evidence here, adding that extra dimension to the aural mix without sounding disconnected. And if you regularly listen to music on your system with a subwoofer in play, those attributes translate into beautifully poised and eloquent bass augmentation.

Compelling proposition

The S/3 SHO’s asking price is not insubstantial, particularly if you do opt for REL's LongBow transmitter. Woofer buyers will no doubt also consider more affordable options. However, this new addition deserves audition – it is a thoroughly compelling proposition in every respect. 

The S/3 SHO looks superb, is easy to setup and delivers the low-frequency goods with movies and music alike.