Polk Signature 5.1 review

This well-priced cinema system loves nothing more than a full-throttle surround mix

In the four decades since it was founded, American audio-meister Polk, based in Baltimore, Maryland, has, as it puts it, been dedicated to 'researching, engineering and innovating toward new sonic revelations'. Its Signature series, although its new entry-level, carries some of these refinements.

This affordable 5.1 speaker system is equipped with Polk’s bass-enhancing PowerPort technology, a Dynamic Balance driver array and an unusually slim centre speaker that can be squeezed into tight spaces under your TV.

On front channel duties in this £1,450 array is the S50, the smallest of three floorstanders in the Signature range (alongside the S60 and S55). The skinny centre speaker in question is the S35, which packs no fewer than seven drivers into its 4in-high frame. Surround sound is delivered by a pair of S10 satellites, again the smallest model in a range of three. 

The current absence of a dedicated Signature subwoofer (one is due around the end of the year) leaves a sub-shaped hole that Polk’s PSW110 is more than happy to fill. It joins the team brandishing a 10in driver and 200W of power in the tank.

American Modern, anyone?

At 95cm the S50 is a little short for a floorstander (as Leia might have said) but that merely heightens its living room acceptability. And the design is unashamedly contemporary, with a smart black-washed walnut finish and a gleaming gloss-black panel framing the drivers. An anti-diffraction magnetic grille preserves the minimal look and snaps satisfyingly into place. It’s a stark, striking aesthetic (dubbed 'American Modern') but curved edges soften things up nicely. 

A gap in the cabinet's base channels Polk's PowerPort system, a bespoke design that increases the port's surface area, which, says Polk, eliminates turbulence and distortion and boosts bass response by 3dB. Dual-floor feet allow the S50 to be placed on carpet or hard floors without the need to faff about with spikes. I love their convenience and eye-catching silver finish, which enhances the modern vibe. On the back you’ll find gold-plated bi-wirable binding posts. 

The midbass drivers used across the system are made from dual mica-reinforced polypropylene, said to offer high efficiency and a linear response, as well as lower distortion. Meanwhile, newly-designed 1in Terylene tweeters extend high-frequency response up to a claimed 40kHz. The Signature range boasts of ‘Hi-Res Audio’ certification. 

The S50s employ two such drivers, while the S10 surrounds feature a 4in version. The S35 centre uses six 3in midbass units, three placed on either side of the tweeter. The centre speaker is every bit as attractive as the S50, and its long, slim cabinet did prove easy to slide into a shelf on my AV rack (there is another more traditionally sized centre – the S30 – in the range).

All of the speakers feature robust, rigid MDF enclosures that feel well put together. The remarkably compact S10 (just 21cm high) caters for wall-mount configurations via rear keyhole fixings and threaded inserts. 

The PSW110 sub is also fairly compact and sports an understated black finish (it also comes in cherry). A 10in front-firing woofer is coupled with a tuned downward-firing port that leverages your floor to achieve maximum bass impact. Terminals include LFE, line-level and speaker-level inputs, plus speaker-level outputs – the latter two using, oddly, spring-clip connectors. Phase, volume and crossover controls sit on the back plate.

Upfront and boisterous

I put the Polks to the test with Rogue One on Blu-ray and they easily capture the excitement of the Star Wars spin-off’s chaotic battle scenes. The Signatures’, er, signature sound is upfront and boisterous, the perfect character for blockbuster movie viewing; the vigorous bangs and crashes grab your attention and keep you immersed in a galaxy far, far away. 

Skip to the beach battle on Scarif and from the off the Signatures enthral you with crisp, crunching explosions and roaring X-Wing thrusters. Sudden blaster shots that send Stormtroopers cartwheeling through the air are dispatched with body-jolting force. The dynamics and power on offer are remarkable for the money.

The system’s scale is also off the chart. It generates a huge soundstage with waves of deep, omnidirectional bass rippling through the room. The PSW110 subwoofer might be the outsider in this setup, and its specs aren't much to shout about, but it doesn’t seem out of place, fusing seamlessly with the Signature towers. The explosion that wipes out Bodhi on the beach has a visceral wallop, while colliding Star Destroyers rumble heartily. 

This package skilfully organises Rogue One's multichannel soundmix, deploying effects accurately and allowing X-Wings to zoom between timbre-matched drivers without any change in tone. This is a cohesive, balanced wall of sound, enhanced by crisp, precise surround input from the S10s.

Despite its unusual design, dialogue comes through the S35 centre in a direct, well-rounded manner. Any worries I had about the multi-driver array lacking coherence were allayed. Radio commands can be easily heard over the din of battle, and the speaker retains the familiar lilt in James Earl Jones’ ominous dialogue. 

Bringing things back down to earth with Kingsman: The Secret Service (UHD Blu-ray), the Polk system again flexes its muscles during the hyper-violent pub-fight scene. The soundstage fizzes with smashing glass, snappy gunshots and crackling tasers, which all adds up to a thrilling listen.

There’s plenty of detail here, too. From Samuel L. Jackson’s lisp to the trickle of water filling the Kingsman dorm, the level of clarity is impressive.

Admittedly, the Polks’ bold approach won’t suit all tastes. Things got a tad shouty when I pushed my Onkyo AVR higher, which drowned out some of those finer details. It’s not unbearable, but I did find my finger sitting nervously over the volume controls. 

Those looking for more refinement and polish from their movie soundtracks might be better off sizing up something from the likes of Monitor Audio or DALI. But if it’s pure, unbridled entertainment you crave and don't mind it a little ragged around the edges, then the Polks should be right up your alley.

The S50 towers are still impressively musical in stereo. Spinning Deacon Blues by Steely Dan, the PowerPort-aided bass response is as advertised, delivering more than enough low-end heft without the subwoofer’s involvement, resulting in a rich and full-bodied sound. Bass notes are tight and overall timing is excellent. It’s not lacking in detail either – ticking hi-hats and strummed guitar are clear and precise. The soundstage gives the various solos plenty of room as they dance in and out, while Donald Fagen’s double-tracked vocal sits nice and prominently in the centre. The only flaw is a hard edge to the sax solo, but it’s a strong performance overall. 

So if you’re looking for a stylish and reasonably-priced 5.1 system that delivers maximum bang for your buck then this Signature pack is worth a punt. It gets a little too boisterous when you push the volume to ASBO levels but that’s a minor negative in a sea of positives. It's good value, and won't fail to bring a smile to your face come movie night. Where do I sign?


Polk Signature 5.1
Price: £1,450 approx 

We say: Polk’s snazzy, innovative speaker system serves up music and movie tracks with verve and vigour, but does lack the outright polish and composure of its peers

Performance: 4.5/5
Design: 4/5
Features: 4/5
Overall: 4.5/5


Drive units: 2 x 5.25in midrange drivers; 1 x 1in Terylene tweeter  Enclosure: Down-ported (PowerPort)  Frequency response (claimed): 33Hz-40kHz  Sensitivity (claimed): 89dB  Power handling (claimed): 150W  Dimensions: 260(w) x 950(h) x 279(d)mm  Weight: 14.51kg

Drive units: 6 x 3in midrange drivers; 1 x 1in Terylene tweeter  Enclosure: 2 x PowerPorts  Frequency response (claimed): 53Hz-40kHz  Sensitivity (claimed): 88dB  Power handling (claimed): 150W  Dimensions: 619(w) x 104(h) x 154(d)mm  Weight: 6.35kg

Drive units: 1 x 4in midrange driver; 1 x 1in Terylene tweeter  Enclosure: PowerPort  Frequency response (claimed): 67Hz-40kHz  Sensitivity (claimed): 87dB  Power handling (claimed): 100W  Dimensions: 137(w) x 213(h) x 158(d)mm  Weight: 2.72kg

PSW110 (subwoofer)
Drive units: 1 x 10in Dynamic Balance composite cone woofer  Enclosure: Vented downward-firing port  Frequency response (claimed): None given  Onboard power (claimed): 200W  Remote control: No  Dimensions: 362(w) x 368(h) x 431(d)mm  Weight: 15.2kg  Connections: LFE input; stereo phono line-level input, speaker-level springclip input and output