JL Audio 13TW5.3 shallow woofer
One of a new breed of compact subwoofer transducers, the JL Audio 13TW5.3 is a non-standard diameter and will have to have a box made to measure as to aperture. It requires a sealed enclosure of just 22.66 litres (0.8cu ft) whose ideal dimensions are quoted in the manual at 19in x15in x 7.75in, or clumsily in metric 483mm x 381mm x 197mm external dimensions. Our box was made to factory standards by Car HiFi Centre in Cheltenham. It’s a solid yet relatively shallow box and the woofer sits proud of the surface by good bit, with a serious cast chassis and a fat top roll surround. The speaker has a massive seven inch voice coil that encompasses its magnet structure within itself a little like the Morel design. However, this woofer drips with JL Audio’s very own engineering. The top roll and bottom linen spider suspensions are held in a special manner. One of the most enormous moving parts I have ever seen in a speaker is the cage-like circle of frameworkery that is used to couple the shallow depth to a cone that can really shift, with good suspension both ways. This thing looks a bit like a high tech Wok trivet and is used to affix the spider. The cone is a shiny pistonic looking thing and is not very dished at all, although it has a parabolic curved part to the edge.
The speaker comes with a foamy under gasket fitted but no screws. The chassis has four lugs around the outside, each with two meaty looking screw hole locations. However, after I predrilled half of the eight holes in the woodwork, I went to screw her down and found that the heavy duty screws I had filched from another subwoofer’s accessories pack in the past were simply too fat to fit through the chassis’ hole and stuck fast. I was a bit unimpressed and felt that although JL would rather you used your own selection of quality fixings and so not have to absorb same in the purchase price, they could have provided a slightly wider aperture to allow for thicker screws. I would recommend you use Steel Allen-headed bolts and T Nuts inside, then the narrow diameter forced upon you won’t matter.
Driving the three Ohm coil was a Vibe BlackBox Bass 5 which meant it was able to deliver more watts than the woofer was rated to. Always useful when it comes to finding limits. I played the dB Drag official CD and Spirit of Sound #6 from Focal.
– Frequency response: not quoted
– Power Handling: 600w RMS
– Injection moulded, Mica-filled, Polypropylene cone with Santoprene surround
– Patented ‘Floating Cone Attachment Method’ technology
– Patented ‘Concentric Tube’ suspension design
– Cast Aluminium tab-ear chassis
– Extremely small sealed-enclosure volume requirement of 0.80cu ft/22.66litres
– 3 Ohm voice coil
– Bright plated 4mm squeeze post terminals
– Voice Coil Diameter: 7 inch (178mm)
– Mounting depth 65mm
– Mounting hole diameter 318mm
– Bolt hole circle 343mm – One-way linear Excursion (Xmax) 9.7mm
– Efficiency: 85.87dB 1w/1M
– Fms: 27.52Hz (free air resonance)
– Qes: 0.511
– Qms: 11.230
– Qts: 0.489
– Vas: 59.47 Litres
Review by Adam Rayner
The first thing to get right is that this is a deeply specific product. Ferraris, MR2s, pickup trucks of all sorts and even stealthy boot-sides are the natural environment of this animal. It is the latest in a long line of possible solutions for the age old issue of raising some bass in less space. Pioneer have a skinny woofer box that you can put luggage on that costs the same as one of these. The JL Audio 13TW5.3 still allows you to keep your luggage space but it is a much more powerful product. Albeit in a serious custom fashion rather than an instant ‘I want it Now!’ solution as you get with the Pioneer TS-WX77A.
The fight to get bass in less space has being going on for years. One method is to make an improbably excursive six inch speaker, put it in a squashed-flat box and rate it to low tones, or even make cunning isobaric twin-six bandpass type things as MB Quart once did. Other than that, a woofer with odd TS-parameters that will bump against little more cubic than its own physical displacement has also been developed by a few makers. The trouble with them was always that even if they could work with little more than tape around their chassis instead of an enclosure, (joke) they were always deep front-to-back. Diamond Audio’s gorgeous original TDX woofer series is a case in point. But that’s all fixed now.
The technology to make a woofer this flat has arisen in a few manufacturers’ portfolios of late but JL Audio have cracked a major breakthrough with this product. All that have gone before have worked more or less but what this does is to bring full enclosed beefy-woofer-in-a-box power to those who have little cubic in their rides. Pull up in an exotic with bass pounding from it and you will perplex onlookers as those witnessing won’t believe the power. This woofer rocks and really thumps the air about. However, I was a bit ticked at not finding any fixings, so do be aware that you will need to go get some and I would bother to get the best. You might want to drill out the holes in the chassis a tiny bit as well, to allow the passage of a fatter screw. The thing looks amazing and the huge seven inch voice coil can be seen, as can the clever plastic frame affair the suspension is held together with. JL Audio are known for their cunning yoke pieces (or they are to saddoes like me) and this is like one of those on steroids. Simply put, it is all about a way to get all the bits to grip together and suspend in a shallow chassis. It’s clever and it works as it enables this incredibly thin front-to-back item to have a healthy normal-woofer style Xmax or cone travel.
The music was more than merely underpinned as I experimented with crossover point and the bass booster function of the BlackBox5 mono amp. The three Ohm load is of course going to suck harder on your amplifier than a normal four Ohm job and the current delivery of my battery, even under charge was exceeded to the point where the headunit coughed and had an identity crisis. Wicking back a tiny bit I balanced it slightly differently and reduced some of the sillier levels of bass boost.
The JL Audio 13TW5.3 can hold great fat bass lines and drop large notes. What it isn’t so good at is the super-rapid stop-start performance of something like the Morel Ultimo woofer which is a �600 SQ paragon. It has low efficiency too, as the huge moving mass must take some energy to make it change direction, even if the magnetic shove is epic. I was able to overload it a tad, at which point it gradually starts to purr as you reach its limits. I found that a really rather low crossover point was best for my application (high power) and that once set well, the sound was controlled and full. It did seem to like some notes more than others, with a slightly peaky output at some upper-end bass frequencies but didn’t balk at being asked to drop and hold some truly low tones as well. I like the very low 27Hz free air resonance of the speaker. This is the mechanical ‘favourite’ or ‘easiest’ frequency of the speaker and coil’s moving assembly. It is springy and compliant but well suspended.
All the above said, I firmly believe that a good long bedding in period would soften the suspension and thus improve the sound a bit. Fresh out of the box, the 13TW5.3 is a little ponderous. But then, as you lean out of your Smart car with one of these fitted in skinny boxes in each boot-flank, you won’t know if the bloke at that show was saying ‘Your bass is ponderous!’ or ‘Your bass is thunderous!’ So it ain’t art but it IS bass. Real bass and now you can wedge it in tight places your mother simply would never approve of.
Sound Quality 7.0
Build Quality 10.0
Power Handling 8.0
Efficiency 7.0
Value For Money 8.0
Overall rating 8.0