Yamaha YST-SW800
£500 Active Subwoofer

Details

It’s a beast in black. The YST-SW800 is among the best subwoofers from Yamaha at the moment, the stylish exterior great components list and modest size are only a few thing on the pros side. The YST-SW800 includes a huge power amp coupled to a very modest driver, and it never seems to fatigue with any sort of sound track.

Measuring around 39x 48x 42 cm H/W/D it has a nice height making it easy to tuck away beside a TV. The design employs a superb driver, and coupled to a side firing port makes it extremely powerful, even though the driver is a mere 25cm size. This downward fires into a dispersion plate. The dispersion plate is part of the base which holds the main cabinet up about 5cm from floor level, each corner is supported by a thick solid ceramic material. The cabinet is very rigid, and helps control the vibrations from the driver. To combat the effect of resonance a port helps the air inside the cabinet breath, so that less resonance is taken to the cabinet (with sealed designs air compress and decompresses suddenly causing some resonance). The low resonance from the cabinet ensure than all vibrations felt through floor, or door or window panels are totally sound waves. What’s more elegant apart from the stylish wood vinyl is the neat control panel on the front; this holds volume control and varying settings like the crossover frequency. This panel is welcome from the usual types located at the rear where all the connections are. And there's the infamous QD bass, and what they all "Dual Bias driver" technology

Internals are a combination of good dampening or wadding and lots of bracing, the driver could easily have been a larger size, as the dimension of the bottom panel would allow this; 48x 42cm which leaves around 20cm of expansion, though at what this driver can do, you wouldn’t want it any larger than it is! At this size it can be easily accustomed to intermediate AV systems, with a room size of something larger than 4x5m to around 7x8m anything bigger and it has trouble filling the room.

As for the other things, the subwoofer driver is extremely powerful, and so should be with a heavy amp load. Oh did I mention the amp puts out over 800w of power to the single driver? With this amount of power, it puts some other sub makers to shame, the equally priced REL Q-150e making a mere 150w! The idea behind the massive power output, I reckon, is that the driver has a very high load or impedance; meaning high power is vital. And the reason it will need this high impedance is to allow the driver to have a very high level of control, i.e. the cone is hard to push. This theory would explain why the power is necessary, since the design uses a port and ports inevitably lower “punch” in sound. Fortunately the amp doesn’t have a huge heat sink on the back, and properly uses the space inside for the heat sink, and also uses the very fluid airflow to help it keep its cool! Well whatever Yamaha had in mind it surely works well.

The connections are fairly modest; it offers either stereo or mono (*subwoofer output on DVD players/receivers) inputs for RCA socket/plugs. It will also take speaker level circuits from your stereo amp and chucks the right crossover frequency to the speakers from the control panel. As for crossover settings, it will adjust from 40Hz, to a very high 140Hz. The range is pretty good, and inevitably the sound improves every time the crossover gets closer to the lower limit. It can produce a good and very flat frequency range, the 25cm driver has no trouble with sub 20Hz frequencies down to 18Hz (-10 dB), although gets a little overpowering at high settings. The port measuring 10cm roughly in diameter has a good effect on the sound, the airflow isn’t quite that fast, but more of short bursts, which is a pretty good sign.

The large volume and driver allows the air inside the cabinet to flow with more expansion, this also increases output and reduces cabinet prone coloration. The port helps the bass extension considerably, and the dispersion plate helps the sound to flow easily.

To put the YST-SW800 in a Hi Fi setup, then the stereo input are a best idea, simply connect the tape loop output or a line output from the amplifier, and connect it via some Phono cables & RCA plugs to the subs stereo input. This changes the stereo signal into mono, by merging the two signals together. It’s a better plan to situate the sub between the speakers, thus helping the crossover be more fluent. All you need do is to select a good crossover frequency (where your speakers roll off at). Or you can simply connect the speaker out put from the amp to the subwoofer and crossover the speakers with the crossover selector – cutting out frequencies to the speakers and putting them through the sub. This method needs the extra speaker cable, but is more efficient.
As for home cinema situations, you can either do the speaker connection method aforementioned, or use a subwoofer output from the decoder part on the system (either the DVD players’ or receivers’). Using a mono phono cable with RCA sockets, the “.1” part or the low frequency channel from “5.1” channel found in Dolby Digital, Pro Logic II, or DTS. This channel covers approximately 20Hz to about 150Hz. You’ll also need to find the lowest frequency the entire system can handle, or the lowest the largest speakers can cope with, and set the YST-SW800 with that frequency.
For the best performance, getting an amp with an extended frequency input, for SACD frequencies, is an excellent idea. The SACD format ensures from 5Hz to 100kHz or more frequency range. I hooked the YST-SW800 to a Kenwood KAF-3030R amp, which has 5Hz to 60Hz, output through the tape loop, but also outputs the 5Hz to 100kHz range through the input labelled Adv. DA/CD, so to get the full SACD output range, the speaker connection is a better idea. Bearing in mind you use SACD, because the standard CD only goes down to 20Hz. The YST-SW800 has a good range, but never comes close to 5Hz, if anyone could ever hear it, (it’s likely the sound will be in the form of resonance).

Testing

First I used the Tape output method, to set the YST-SW800 up with some old Mission 701’s, and a pair of M71’s too. The 701’s have a lower extension of 58Hz, so this was easy to setup. This method allowed a large void of frequency to be covered by the YST-SW800. Even more so when the M71’s at a very respectable 65Hz, were connected in the same method. However upgrading to bigger speakers, the JM Lab Chorus 715 to encourage performance from the YST-SW800, at their rating of 45Hz. At first with the smallest speakers, the YST-SW800 works excellently. At first the subwoofer appears to behave extremely polite. It never seems over emphasised, the sound is crystal clear, the entire range, isn’t just a boom its more pronounced. The low end can take your breath away. Simple music construction is easy to pick apart; the sub reacts, starts and stops the instant the note or effect ends. Rendering it a very powerful and punchy listen at this early stage. I later added it to the speaker connection method. In this situation the crossing over of the sound became more smooth, the lines output seemed to mildly cross without rise or fall, making the sound more transparent, and very pleasant.

Next I tried it with the 701’s. In the tape method, it works slightly more potent, while not exactly a step up. The crossover frequency seemed a little too high, so I lowered it to 50Hz-ish, which improved the exchanging notes. But it definitely works better with the speaker connect method, the YST-SW800 has some great filters and components making the crossover work with great precision, it also helps the sub determine what sort of volume it should run at.

Next the Chorus’ 715 and I didn’t bother with the tape method, but while the sound definitely improved, it wasn’t the subwoofer. True the new speakers make a better effort to pronounce the bass, but apart from that the YST-SW800 has no real benefits with music at these higher figures.

To test the sub I first tried music, which worked well through all types of crossover settings. The YST-SW800 has no trouble with bass-drums or bass lines which run over drum beats. Anything from the Stereophonics work to Rage Against The Machine are handled well; controlled pronounced and very subtle. The sound is far from the usual “boom-boom” subs you here at lower price levels, the sound sort of matches the music character, it is never overpowering, over emphasised or exuberant.

Turning to movies, the YST-SW800 packs a heavy punch here too. With such scary work found on Saving Private Ryan, the YST-SW800 has a real treat in store, the bassing explosions suddenly are more real, as if they’re in the room. True with DVD’s you only get the 20Hz limit, but this is low enough to to rattle everything in sight, and everything not in sight, such as teeth, rib cages, and the internal organs, which can be an odd feeling.

The sub worked especially well in room sizes from 4x 5m large, going up to a maximum of 7x 8m where it could be a little lightweight considering its small driver for the large room. With smaller rooms it would dominate everything, and don’t even consider putting it in a cabinet, the YST-SW800 is made for open surrounding operation, and so anything such as a hard wall will reinforce the sound and make it bloated.

After a few more days of use the YST-SW800 becomes less attractive in a few areas, but they’re fairly minor. It became more apparent that for music it wasn’t a star, the sound lacked true agility, and was sort of biased to the high bass lines, and lower bass was a little soft. You might think stuffing the ports helps, but I can’t think of anything that would bloke these ports than a lot of glue and a lot of MDF. I recall a DIY subwoofer blowing apart since it was a sealed design and using a large 12” driver. Anything like old socks will be pushed out. However with movies it is the star, it never seems provoked and can eat any soundtrack.

The YST-SW800 is a compact subwoofer; it offers a great level of refinement, and great controls. The sockets are in modest numbers but are all one could want The design is very unique allowing the sound to be very impressive, the dispersion plate works well as does the side firing port. The healthy power supply of a whole 800w is plentiful to fill rooms sizes of up to 7x 8m and has no trouble eating movie and music tracks with equal aplomb. And for overall performance there is little that can beat the YST-SW800 for this money anyway.

Music Sound: ●●●●○
Movie Sound: ●●●●●
Build Quality: ●●●●●
Compatibility: ●●●●●

Overall: ●●●●●


Recommended: Yes

Amount Paid (US$): £500$686