Breaking away from conventional in-ceiling speaker form factor, the Soundsphere range of omnidirectional speakers offer an ideal solution to a tricky problem. Stephen Dawson explains.
Installation speakers tend to clump into two categories: in-ceiling/in-wall speakers, and higher end PA-style loudspeakers. Each has its benefits and, unfortunately, its weaknesses. So in which of those two categories does Soundsphere’s range of speakers fit? Neither… or perhaps both.
Soundsphere has a number of models in its range, so we’ll use the review unit – the Soundsphere TC110B Compact loudspeaker as a model for the lot. They all conform to the same basic design.
The problem with PA systems tends to be expense and directivity: the sound is projected in a specific direction. The problems with in-ceiling speakers can be many: the need to make holes, the directivity (sound goes mostly downwards, or in the direction an adjustable tweeter is pointed), and distance in the case of high ceilings. The Soundsphere is ‘attached to’ rather than ‘embedded in’ the ceiling, so there are no big holes. It can be suspended from high ceilings, bringing it down to the level at which it can provide the most effective performance. And it is omnidirectional, sending its sound in a 360º dispersion pattern horizontally, and 180º vertically – that is, it produces a hemispherical sound field.
This is achieved by mounting the driver – a 165mm full range unit – on the face of what is otherwise a 254mm sphere. This face is held a few centimetres away from a shaped reflector, the two parts held together by three connecting sections. This device is mounted above the heads of people in the space it is covering, with the driver firing upwards into the reflector. The reflector is sculpted into a shape which ensures that the sound from the driver is, well, reflected out to the sides and back over the body of the sphere, down towards the people are.
Soundsphere says that the review model is intended for ‘seamless background music and clear voice announcements’ in a wide range of commercial and community settings. As such it seems to have been optimised for a moderate frequency range with the capability of high volume levels.
Soundsphere gives somewhat different specifications for the unit on its product page on the website, and on the downloadable PDF. I’ve gone with the latter since it is more detailed and includes full performance charts, including sound dispersion graphs. The speaker is rated as having a sensitivity of 96dB with 2.83V input, measured at 1m. The maximum output is specified at 108.5dB SPL at 1m. That’s certainly getting a lot of sound out of the delivered power.
The frequency response is specified as a 100 to 20,000Hz, -10dB, and 220 to 18,000Gz, -6dB. Not exactly high fidelity, but fairly good for the stated purpose. The nominal impedance is 4Ω. Power handling is 35W.
There are other options when it comes to driving them. A line matching transformer (with taps for 25V, 50V, 70V and 100V systems) is available, and also an amplifier module. These fit into the space behind the reflector, ensuring the visual styling is not marred.
The unit requires no assembly. It comes fitted with three wire cables attached to assist hanging, but ceiling fitting brackets are also available. The unit is made from structural foam polystyrene, finished in what I’d call pale cream or off white. Soundsphere just calls it white. Custom colours are available, but it is also paintable.
There are seven models in the Soundsphere range. These include weatherproof models, models with coaxial tweeters and bass/midrange drivers, and drivers in sizes of 165mm, 200mm, 305mm and a massive 380mm. That last is specified as being good for over 120dB of output. For fuller range performance, the Q-SB2 Sub-Bass Supplement spheres can be added. These pack two 457mm (that is, 18”!) drivers, capable of handling 800W and delivering up to a 128dB sound pressure level.
There’s really not much to say about installation. A sheet included with the speaker describes how to do it. It’s just a matter of hanging or screwing it on (best to use the optional mounting bracket for this). There are also screens available – perforated rings, one designed to protect the driver cone from damage, the other from both from damage and weather. The gap between the reflector plate and sphere is wide enough to admit a squash ball, but not a tennis ball.
The speaker wires – these are very thin – snake through one of the connecting sections between the sphere and the reflector plate, so you make the connections behind that plate, keeping things out of sight even when the speaker is hanging.
The height of the speaker system, from the bottom of the reflector plate to the top of the sphere is 302mm. Obviously this speaker would not be suitable for use in places with low ceilings.
One thing soon become clear once I’d wired up the test speakers: this speaker produced a lot of sound from a small amount of power. I started with some music delivered from a high fidelity amplifier rated at 30W, keeping things realistic. The speaker went extremely loud quite effortlessly. Importantly, it retained clarity and tonal balance while doing so.
To really push it I played some Rage Against the Machine, since the strong bass section, the complex guitar rhythms and the powerful drums can mask the clarity of the largely spoken vocals. But even with the music running to peaks of 105dBSPL at 1m, it remained perfectly clear and clean.
There was no deep bass at all, of course. The middle bass was a bit sketchy, but there was enough of that, combined with the upper bass, to give a satisfying enough grunt to the whole thing.
I ran a range of easy listening and classical through the system at far more restrained levels, too, cognisant of the ‘background music’ function, and it delivered all this smoothly.
I also played a number of recordings with a range of male and female spoken voices, and clarity was excellent, with little to no boominess of the male voice, even if close miked, and a clean and restrained sound to the female ones. The character was retained even with the volume wound up to quite high levels. These are excellent speakers for announcements, and possibly for also for narrating live events.
Even though the sphere – the body of the speaker – sits between the reflector and a person directly underneath it, the sound didn’t seem to change in tonal character or clarity when heard from that angle. The sphere seems to allow even the higher frequencies to travel cleanly around its exterior so that they can be delivered downwards.
Indeed, the tonal character of the sound was remarkably consistent at all realistic positions. I am confident that if these were deployed at regular intervals, there would none of that effect of moving from island of sound to island of sound so typical of normal ceiling speakers.
I confirmed the claimed sensitivity specification of the speaker, with it scoring 96dBSPL at 1m using a 500Hz to 2,000Hz bandwidth limited pink noise signal.
The Soundsphere TC110B speakers – indeed, the whole Soundsphere range – provide a different and useful way to deliver so sound to public areas. Well worth checking out.