A rapidly-growing product category consists of horizontal speakers which sit under or near a flat-panel display yet manage to produce some sense of surround sound. For the concept’s earliest days those from Yamaha Music have been among the best and certainly the most high tech.



This bar packs in 40 small drivers, each measuring 40mm, and each with its own little power amplifier. A digital signal processor individually tunes the signal delivered to each of these drivers, allowing them to work in groups and ‘project’ beams of sound in specific directions. These are supplemented by a couple of 110mm bass drivers.
The surround effects are achieved by using the beams to bounce from rear and side walls, generating the impression that there are speakers in those locations.

There have been a multitude of enhancements in this most recent version. One of the most significant is physical: the unit has been trimmed back to a mere 90mm deep, allowing wall mounting without the marked protrusion of the previous model. It also measures 1030mm wide and 210mm tall. The 42 drivers are hidden behind a grille, underneath which are a small number of controls and a tasteful but informative display.

The unit now has four HDMI inputs, allowing it to support all your source devices, and these are fully HDMI 1.3a compatible, including automatic lip-sync support. It also supports the new audio standards from Blu-ray, including Dolby TrueHD and DTS-HD Master Audio. It offers a new sound projection mode called 5Beam2 to provide its front-projected version of seven-channel sound.

The previous high-end model came with an iPod dock, and so does this one. But the dock with the YSP-4100 is a revolutionary advance. It is based on Yamaha’s proprietary AirWired technology, so your iPod stays in your hand.

The unit is bundled with the YST-SW225 subwoofer, a significant performance boost. This is a 120 watt, 203mm bass reflex subwoofer, with quoted frequency response of 28 to 200 hertz.


Setting up the YSP-4100 is very easy. Just mount the main unit on the wall or shelf where you propose to keep it. Then plug in the cables from your source devices, the output cables to your display, and the subwoofer cable out to that. As it happens, we were supplied an AirWired client which could be plugged into the subwoofer. Since the YSP-4100 also has an AirWired transmitter, we were able to skip the wiring to the subwoofer. (The client is a $299 option.)
Then we plugged in the calibration microphone, put it on the supplied cardboard stand in our normal seat, pressed ‘Enter’ on the remote control and, as instructed by the on-screen display, left the room. Three minutes later a chirp informed us that calibration was complete.

This left the subwoofer level up too high, to the point where we felt the need to turn it down significantly, using a test disc. Having done this, the sound was remarkable. It has been awhile since we last listened to one of Yamaha’s Digital Sound Projectors, but our sense was that this model had lifted audio quality by quite a large degree. It offered excellent tonal balance and superb detail.

The surround performance was quite good, but we caution readers not to expect too much. Precisely-defined sounds that were supposed to come from well behind us did not, in our room, present as precise an image from the desired direction as we would expect from well-calibrated 5.1 or 7.1-channel speaker system. But neither did they come from the front. It was more that they were disembodied, spread about. This resulted in a nice airy feel to much program material and an enormously deep front sound-stage. With ambient surround the effect was far more in keeping with discrete surround speaker systems. Still, the results were at the least as good as any of the competing technologies, and often better.

The iPod dock is wonderful. If you’ve seen how the company’s PDX-50 iPod dock works, this is the same. So a really compact transmitter unit fixes onto the base and rear of your iPod. This can then slip into a charging cradle which is separately powered from a power point. Once you select the iPod input on the YSP-4100, it comes under the control of your iPod. You set the volume by using the iPod’s click wheel. You navigate using the same old controls you’ve always used, except that the sound comes out of the sound projector instead of earphones. Hold down the play/pause key of your iPod to turn it off, and the Yamaha turns off as well. Start up your iPod again and the Sound Projector starts up. In the difficult electromagnetic environment of our offices, the range was limited to about ten metres, — that’s enough, and the method of control is marvellously liberating.


To top it off, the YSP-4100 costs $800 less than the previous YSP-4000. If you want front surround sound without the wiring, this one is definitely worth close inspection.

Yamaha YSP-4100 digital sound projector
Price: $2499 (includes YST-SW225B)
Warranty: Two years


  • Excellent front surround sound solution
  • Good subwoofer included
  • Brilliant wireless iPod dock


  • Not as good as separate surround speakers