BluCube Universal Fire & Acoustic Speaker Hood

The majority of ceiling speakers have cut-out apertures ranging in diameter from 200-250mm. The aperture of the BluCube Hood as delivered is 200mm but it can be enlarged by simply cutting the fabric. A guide is marked on the flange which is the typical diameter of an 8-inch driver speaker. There is a sewn seam to keep the fabric neat. It is preferable to avoid cutting this seam. If however, the hood needs to be cut to fit a speaker located close to a joist, it may be necessary, on occasion to cut the aperture offset from centre to accommodate the location. This is easily achieved and does not affect the performance of the hood. Please check our installation video for more details.

Firstly, it makes the hood easier to fit but, more importantly, it performs significantly better because it is possible to create a much more effective seal. Speakers are fitted from beneath the ceiling not from above. The inner flange means that the flange can be easily fixed to the upper surface of the ceiling plasterboard because the flange is accessible from inside the hood. An external flange is not, and is thus impossible to seal effectively. An effective seal means that way the fire protection performance is maximised, as is the acoustic performance. Even a small gap under the flange weakens both of these aspects considerably. Dust ingress is also minimised thus protecting the speaker better too. The inner-flange makes the hood adaptable to many types and sizes of in-ceiling speaker. It also allows for offsetting the aperture where a speaker aperture may be close to a joist. Finally the inner-flange means that the speakers fixings (often referred to as “swing-dogs”) clamp the fabric of the hood to the upper surface of the ceiling making for a much better fit.

The BluCube hood is compressible without affecting its performance. Providing your speaker itself has sufficient clearance, you only need 2-3mm additional clearance to accommodate the fabric of the hood. Although the extended height of the hood can accommodate speakers with a depth of up to 200mm, it can be compressed to comfortably accommodate speakers with a smaller depth requirement. In short, the hood will fit almost any depth of speaker typically used in ceilings.

In an ideal world all speakers would be central to the joists. This is very often not the case. Provided that the speaker itself can fit in the aperture and the speaker’s fixings to do not foul on the joist you should be able to also accommodate a BluCube hood. There are two ways to do this. The first is simply to scrunch the fabric of the hood against the joist so that the speaker will fit. This will not affect the performance of the hood or speaker. If the aperture is too close to the joist to allow this then the second approach is to cut the fabric of the hood to create an offset (elliptical) aperture. Again, this will not affect the performance of the hood. In this case it may be necessary cut through the sewn seam on the flange and this will expose some of the foam. You may need to then glue this back in place. Because the aperture of the hood flange is now enlarged and offset it may be that only some of the speaker fixings clamp the flange the hood fabric. This is perfectly acceptable but it is advised that in this case the flange is firmly affixed to the surface of the plasterboard before fitting the speaker.

BluCube have conducted extensive tests in this area and we estimate the typical sound reduction to be of the order of 2dB following the addition of our hood. This will vary from installation to installation and so this is a guide only.