By far its most distinguishing feature is a front mounted neodymium motor, a design that I haven’t really seen since the days of Illusion Audio. By mounting the magnet upfront, the designers at Diamond have produced a subwoofer that is among the slimmest even compared to its peers. Most shallow subs I have installed come in at around 3.25 to 3.75” in mounting depth; the S104, needs a mere 2.7”. While this may not seem like a huge amount, I can tell you from experience that every millimeter counts when you are trying to save space. This miniscule depth requirement also means the S104 is the shallowest sub I have ever used, beside the JL audio TW5, which does not come in a 10” form and is substantially more expensive.
Now I have to admit that going into the review, I was not overly optimistic about this particular subwoofer. When perusing the manual, one number jumped out at my right away: 5.7. As in 5.7mm of Xmax (Linear Excursion). In today’s world of long throw, monster output woofers, having a rated travel of less than 10mm is pretty rare; as a matter of fact, 5.7mm is at the low end even for a shallow mount sub meant for sealed enclosures, treading dangerously into the mid-woofer territory. Coupled with a free air resonance of 37.7 Hz and a RMS power handling of 150 watts, I was pretty concerned that the sub would be more of a dud in the test vehicle, a 1998 BMW M3 Sedan, which isn’t known for the best bass response to begin with. To calm myself, I kept on repeating the mantra of “specs don’t mean everything”, and started the testing process.
Overall Design and Build Quality
As stated before, the cosmetic factor of the S104 is dictated by its unusual front mounted motor with its jacket of what appears to be cooling fins. If you distract yourself from this one aspect, the rest of the subwoofer is pretty standard. A concave carbon fiber cone held to the chassis by a medium sized surround, which to me seems a little fat considering the low excursion rating. A black basket featuring eight mounting holes completes the picture. From a purely cosmetic aspect, I would like to see a taller gasket with recessed mounting holes so the screws won’t be as visible.
Flipping the subwoofer over once again gives you the appearance of a normal driver, sans the magnet of course. The basket itself seems to be quite thin but not unusual considering its light duty nature. A 2” coil and a single spider of around 8” in diameter are located at the back of the subwoofer. Two spring loaded binding posts are positioned at two opposite ends of the structure and there seems to be plenty of venting available throughout. I am far from a technical expert so I won’t comment on the design aspect of the product, but overall, it would seem that the S104 is a well built piece of kit.
Handling the subwoofer reveals that it is extremely light weight (well under 10 lbs by the feel of it), and while its looks may not be for everyone, I find the combination of front motor and the Carbon Fiber cone works well to present a futuristic theme that I would be more than happy to incorporate into my projects.
For a full list of specifications on the S10.4, please download the product manual at Diamond Audio.
Ease of Installation
When it comes to ease of installation, Diamond’s unique design is somewhat of a double-edged sword. On one hand, the sub itself is exceedingly simple to mount; simply cut a 9.3” hole in an enclosure that’s more than 2.7” in depth and it pops in without a problem. The lightweight design means you can easily hold the sub with one hand and drive in the first few screws with the other in virtually any orientation. The binding posts are far enough in board so getting wires caught on the baffle opening isn’t an issue. For the purpose of this review, the subwoofer is dropped into a .55 cubic foot sealed enclosure, residing in the spare tire well of the M3. It is worth noting that the spec sheets calls for a .6 cubic foot box but this was the biggest I can do given the physical constraints of the vehicle and I stuffed the box full of polyfill to try and compensate for this discrepancy. Once the enclosure was ready, the installation process took less than two minutes. The sub came with a foam gasket already attached to the bottom of the mounting frame, which is a welcome departure from the norm. Once screwed down, the sub formed a perfect seal with no sign of air leaks.
On the flipside however, because the top of the motor sits about half an inch above the tallest part of the surround, some extra attention is needed in order to fit a protection grille above the sub. If you never planned on putting a grille in front the sub, then this is a non-issue, as the extra half inch of spacing above the cone is pretty standard as to ensure the surround does not slap any solid surface. For this install, however, I had to make the top fake floor opening ¾” thick versus the normal ½” to accommodate this protrusion. Overall, I feel that the extra work involved was a pretty minor inconvenience that took up less than half an hour of my time.
Simply put, this is perhaps one of the easiest subwoofers to drop into a box owing to its shallow depth and miniscule mass, you just need to plan ahead to account for the front mounted magnet in your installation process.
Output and Sound Quality
For this M3, a customer supplied Soundstream 705 five channel amplifier powers the entire system. When switched to high-power mode, the mono channel of the 705 provides the subwoofer with a rated 200 watts RMS at 4ohms, well suited to the S104 (which only comes in single 4ohm versions). The front stage consists of a set of Seas Lotus Performance 6.5” two way components, a speaker known for its detailed and powerful midbass response, which puts more demand on the Diamond sub’s output characteristics in order to keep up.
Using an Eclipse CD8053’s internal crossover, I gave the sub an 18 db/octave slope at 80 Hz and started running through my normal set of demo songs. The first track is an old sound quality standard, the live performance recording of the Eagles’ Hotel California. When the first bass note hit at the :32 mark, all my reservations about the S104 evaporated. The bass was full with good impact, easily filling the entire car and keeping up with the Seas’ midbass attack. The low frequency extension was average, but far better than I expected from a mere 5.7mm of travel. At a moderate to high volume, I did not notice a huge difference between this and the subwoofer system in my own car, which is an Image Dynamics IDQ10v3 (19mm Xmax) running off 780 watts RMS.
Next, I played a dynamic drum track featuring a wide variety of instruments. Once again, the S104 had no problem supplying the adequate bottom end reinforcement. The individual beats of everything from snares to kick drums all came together as a single entity, showing the sub is quick on its feet with good transient response. The overall impact isn’t as good as my car, but some of that can be blamed on the relatively under powered front stage (50 watts x 4 active).
Nils Lofgren’s live recording of "Keith Don’t Go" was next in line. The Guitar has amazing detail yet some nasty lower end bite to it as well. The Seas set did its part in reproducing its share of the music, and the S104 held up its end of the bargain as well. In fact, this type of music really suits the sub since there isn’t a huge amount of ultra low frequency information. The bottom end attack of the guitar came through smoothly and without much coloration, and the slaps were distinct and full of impact. Throughout the entire track, I never once felt that the sub was struggling to keep up with the music or localizing to the back of the vehicle.
Interested in seeing just how much output the S104 can dish out in a real world listening scenario, I punched up Dr. Dre’s "Nuthin but a G Thang". The fat bass line is a workout for any subwoofer, let alone one with such limited Xmax and power handling. But once again, I was pleasantly surprised. The sub did a decent job of producing the meat of the bass, filling the cabin pretty well and giving the rear view mirror a subtle rattle. But in the end, it is a simple matter of physics that this type of heavy hip-hop will easily expose the S104’s limits. With the volume cranked to a pretty high level, I can hear the sub start to bottom, a fact verified when I opened the trunk and listened closer. The bottom end extension also seems to drop off below 30 Hz pretty dramatically. I listened to the same track immediately in my car. While the IDQ isn’t a super bottom end monster, it certain shows that a shallow sub with low excursion isn’t truly meant to play into the subsonic range. It should be noted that despite about 5 minutes of repeating this track at a pretty high clip, the S104 released no tell tale signs of the magic smoke, and no traces of burning voice coil was detected what so ever.
Overall, my fear of having to qualify each statement with the phrase “given its low excursion and power handling” was entirely unfounded. The Diamond HEX S104 more than held its own with the wide variety of music I threw at it. If you are into heavy hip hop, R&B or bass tracks, this is probably not the right driver for you, but for virtually all other types of music, especially rock, I am confident that the S104 will perform up to, and perhaps even above, your expectations….DESPITE its low excursion and power handling.
In conclusion, the Diamond Audio HEX S104 is a solid player in the shallow mount subwoofer market. Its light mass, tiny mounting requirements means the unit is well suited for those with strict space and weight limitations. The output characteristics were totally unexpected and really reinforce the notion that you cannot judge a subwoofer by its spec sheet. I look forward to future releases of this subwoofer that will build up on its solid foundation.
Pros: Cool looks, shallow depth, low weight, well built and good sound quality and unexpected output
Cons: Somewhat pricey, protruding magnet upfront, has limits when it comes to SPL and extension
|< Prev||Next >|