Sound Reflection

It all starts with the humble reflection. Surfaces, hard or soft, all reflect sound in one way or another. Harder surfaces will typically reflect sound clearly and accurately, whereas softer surfaces will soak up some of it. The problem is that reflections can later reconnect with direct sound from a monitor or instrument, blurring what we should be hearing via problems such as excessive reverb, comb filtering, flutter echoes and standing waves

Bass Traps

A basic bass trap is simply a deeper absorber. Low-frequency wavelengths are very long; in many cases, longer than the length or width of your room. For example, a 50Hz waveform has a wavelength of 6.8 metres. We cannot assume that a typical absorber, described above, with a shallow depth will soak up these wavelengths. To use absorption, we need to gain depth, and as bass often lurks in the corners of your room, enter the corner bass trap.

Other forms of trap exist that are not based completely on the same static form of absorption but resonate, instead. The Helmholtz Resonator can be extremely effective at tackling many problematic frequencies, but it must be constructed and tuned with the room modes in mind. Some approaches blend both absorption and resonation by utilizing barrier matting or another dense material suspended within a frame and with a layer of dense rockwool to the rear. It is the surface area that determines the frequency at which the trap works, but they cover a wider band than the tuned Helmholtz.  

Sound Absorbers

Absorption is the easiest course of treatment as it immediately improves your acoustics with only minimal installation. Essentially, an absorber is constructed using a soft porous material capable of dissipating sonic energy as it tries to pass through it. Absorbers such as mineral wool fibre in timber frame or from reliable manufacturers are known as broadband absorbers as they will absorb a wide range of frequencies.

First, purchase our mineral wool fibre preferably 1,200 x 600mm slabs (not loft insulation) with a density of at least 30kg/m3. These come in a range of depths, but somewhere between 50–100mm is ideal. From 3 x 2-inch timber you can construct a frame that will look very attractive hanging on your studio

Taking this frame principle, a huge step further, you could line the whole of your room with a 3 x 2-inch timber framework. You could then place absorbers throughout your room, resulting in a more dead-sounding environment. This kind of broadband absorption will eliminate many potential problems within your room; however, key issues and problems in the bass end will remain

Sound Diffusors

Diffusion is an excellent way of ensuring that the direct signal from your monitors reaches your ears uninterrupted. The theory of diffusion is to scatter sound around the room as much as possible rather than reflecting sounds in the expected pattern. If you draw a bird’s eye view of your studio and plot the line from your monitors to the side walls reflecting to your ears you will find the point at which a diffusor would be best employed – what I’ll call the ‘mirror’ point. Placing a diffusor here will scatter the signal away from your ears and assist in clearing up the focus and stereo width of your mix.