Company & Subwoofer Overview

The latest REL offering, the 15-inch HT/1510 Predator II subwoofer, might just be their best value yet. This is a completely revamped version of their already successful original 15” subwoofer in their HT series. In this day and age of ever-increasing prices, the great news about this model is, while it has been completely redone with more expensive materials, it will sell exactly the same price as the old model.

REL has always been unique because they focus on just one single type of product - subwoofers. Their team is extremely passionate about pushing the boundaries of engineering to the limits to improve the performance of their subwoofers. They have gained a very devout following of REL fans over the years as their subwoofers do more than just add deep bass to your system. A properly set up REL subwoofer can improve the entire listening experience.

Learn more about how to properly set up & calibrate a subwoofer >

REL has taken the role of a subwoofer in a great music or theater system to the extreme with their 6-pack concept where they have designed a system that allows you to stack up 3 subs per channel in a really cool vertical configuration. That whole idea is kinda neat as some of the very best-sounding subwoofers we have ever heard over the last several decades all used multiple stacked drivers.

Design & Build Quality

When REL was starting the design of their update on the 15” Predator subwoofer, they heard from many customers that they wanted something that looked as good as the other subwoofers in the upper REL series. The original Predator was pretty basic looking, but they really stepped things up with the new version. One reason for this is many REL owners had paired up one or two of the Tx, S, or Reference models with their main speakers and were adding a 15” Predator for the LFE channel. Their request was to make the Predator look cosmetically similar to the rest of the line.

The new Predator II now comes with a sleek new look with proportions that better match the other REL models. This big guy now looks very nice to the eye with better finishes.

To us, all REL subs seem to be built really well. Fit and finish is great, you will always find nice connectors, and really smooth feeling solid adjustment knobs on all REL subs. The new Predator is no exception and even has balanced audio inputs along with RCA.

Another cool design feature is the ability to stack up 3 of them for incredible bass performance. The subs come with REL Couplers™ that connect lower units to upper units. The couplers are made out of solid milled aluminum and pair up with rails that are on the underside of each sub so you can create your own true bass tower of power. Those of you who have been lucky enough to experience a stack of RELs know how prodigious and effortless the bass is in this kind of configuration.

Subwoofer Features & Technology

The REL HT/1510 Predator II subwoofer is designed for home theater and music systems although we think it will mainly be used in performance home theater systems. Like most subwoofers, there are two sets of RCA inputs and a pair of outputs.

Unlike most subs in the price class, you also get a balanced audio input and out. You can set the sub to come on when it sees a signal with a switch on the rear panel, which is what we suggest.

Like we see in most subs, there is a level and crossover control. However, as we said earlier, these potentiometers feel really smooth and solid, somewhat like a high end preamp.

Right above the two controls are a phase switch you can set to 0 or 180.

We have to compliment REL on the way they label things. Just like our friends at Cambridge Audio, the connections and controls are screen printed both right side up and upside down so when you are leaning over your sub, you can see them in the upside-down position.

The new Predator 15-inch subwoofer model has been redesigned with all kinds of new tech for better performance. While the cabinet was redone to be much more elegant and match up with the other series better, there are some internal changes REL made to squeeze out better bass performance. They have always had what they call BrilliantBrace™ tech which cradles the rear of the woofer that takes energy that would normally be trapped in the driver and reduces cabinet noise. The new design lets the driver's back wave use the entire depth of the cabinet for more output and better control of the driver itself by working with the pressure wave. This idea took some serious engineering and testing to finalize. The feet of the cabinet itself are now very solid stacking rails which adds to making the cabinet more inert.

REL is all about speed and while it may not seem like much, they improved the input filters to make things even faster. Better speed equates to passages with bass slam hitting you even harder and quicker.

The original 15-inch Predator subwoofer already had a great driver, but REL made some improvements to allow for even more power handling. The woofer is a combination of glass fiber and a center cap made from carbon fiber. The glass fiber material is very lightweight and allows the large 3” voice coil to instantly move the driver for great attack. To hold everything in place and keep things rigid, a carbon fiber center cap is used rather than continuing the center cap with the same material like many sub drivers have. This very stiff center cap keeps the shape of the cone perfectly intact even when a tremendous amount of bass hits it. We love this design's goal of having incredible speed, as it not only benefits movie soundtracks, but means the 15” driver can keep up with fast tower speakers for music enjoyment as well.

The new version also gets an updated amplifier. REL uses 4x 400-watt mosfet output devices coupled with a huge power supply to deliver 1000 watts, just for the one 15” driver. Loud, deep bass content is very demanding on amplifier current and can suck the life out of a wimpy power amp. The large power supply has tons of reserve so even a constant barrage of deep bass will not cause the amp to lose control of the driver. This sounds like a broken record, but this big amp and power supply are all about giving the new Predator even better speed and attack, which make those effects and deep bass in music sound more realistic.

So we’ve got a better cabinet, improved power handling on the special 15” driver, an even beefier and more powerful amp, improved foot rails, and reduced input lag. All of these tweaks to each part of the original 15” Predator add up to a big improvement anyone can hear. And like we said earlier, the best part is the price is exactly the same as the original!

Subwoofer Performance

We decided to give this new 15-inch subwoofer a tough test and pair it up with some gear a bit above its pay grade. We’ve been having a ton of fun listening to the KEF Reference 1 bookshelf speaker.  This is one of the fastest bookshelf speakers we have ever heard with a super transparent midrange.  The rest of this two-channel system was a McIntosh 7200 stereo receiver using the REL crossover built into the subwoofer and just letting the speakers roll off on their own, similar to how REL recommends their more expensive subs to be used. The source was a HiFi Rose RS150 streamer.

Our expectations were that a 15-inch subwoofer would have a hard time keeping up with a speaker like the KEF Reference 1. Typically we would pair these with a much higher end REL or something like it with a smaller woofer.

We played an old classic, “Gold Dust Woman” from Fleetwood Mac, to start working on dialing in the crossover and level. If you know this track, it has a repeating kick drum with a good bass line. It was pretty obvious here if we had the crossover set too high, but eventually we got a very nice blend between the KEFs. Surprisingly, the REL kept up really well adding that bottom end punch on the bass drum.

Next up - Charger by Elio. This is all electronic and starts out with another drum beat then gets into a lot of electronic bass. On this one without the sub on, we just missed the entire bottom octave. The REL blended great and really filled up the room with fast deep bass.

“Oh Yeah” by Yello.  This has some fast electronic bass that will really show if your subwoofer has some overhang and we did not hear much at all here. Was it as fast as the bigger, more expensive REL’s we have heard? No, but for the cost, it did a fantastic job.

Finally, “Sub Bass Excursion” from Bassotronics. The HT1510 Predator II reached down deep on this track. While not as deep as some other subs we have tried, it was excellent for its cost.

Our overall impression was this sub can produce tons of deep bass energy and for a subwoofer that gets down as low as it does, is super fast. Of course when you build a driver, cabinet, and amp like they have in this almost 100 pound beast of a subwoofer, you would expect it!

Explore home theater subwoofer placement options >

Overall Recommendation

We see the HT 1510 Predator II mainly being used in larger-sized home theaters to provide that awesome bottom octave. The great part is, when you start playing concert videos or just using your theater for music, it will not add blur or smearing to your main speakers.

For music systems only, the REL S510 at about 30% more is probably a better choice, as it is even faster for better blending. We were just really impressed at how fast the HT1510 was in our testing.

Just bear in mind it will likely be a team effort to move it!