September 2009

A very common question is: how do I acoustically treat my room so that I get the best from my monitors? Well, this is a very large subject area covering room geometry, reverberation and decay time, sound reflection and refraction, material properties, etc, so we will just give here a checklist of the most important features that a listening room should have.

• First, choose or build a listening room that does not display any parallel walls. Parallel walls should be angled at a minimum of 15 degrees each to be considered then non-parallel at all frequencies.
• Ensure that the reverberation time is both low and smooth with frequency. RT60 usually increases towards low frequencies, but make sure it rises slowly without any peaks.
• Primary sources of reflection should be treated so that reflected levels are at least 20 dB down from the direct sound pressure level.
• In general, if diffusers are used they should be placed to the rear part of the room.
• The front wall should be a hard, heavy and smooth surface if flush-mounting of the monitors is to be used.
• The front wall can be absorptive if free-standing monitors only are being used.

Once the room has been acoustically treated the monitors can be installed:

• Position the monitors according to international standard angles.
• Position the monitors in the room so that any cancellation effects from side and rear walls do not affect the low frequency region.
• Angle the monitors and their acoustic axis towards the listening position in the horizontal and vertical planes.
• Set the acoustic tone controls as suggested in the Operating Manual/Quick Setup Guide to give a flat frequency response.