Beyond the settings for the monitors, additional tweaks may be desired to improve the response of the system and room environment. You may discover that a reflective surface is causing a high frequency anomaly or perhaps room modes are disturbing the bass response.
First reflection treatment
Sound reflecting off hard surfaces that are close to the listening position can cause problems in the high frequency response and imaging of the monitors. In many cases, these first reflections are relatively easy to fix. Figure 7 shows some common causes of first reflections in a typical control room.
First reflections can be located easily by using a mirror placed on various surfaces in the studio to check if you can see either monitor in the mirror while sitting in the listening position. If you can see either monitor in the mirror, upper frequencies will bounce off that surface directly back to the listening position and potentially cause response problems.
Placing absorptive material on these surfaces will reduce the effect of first reflections and improve the sound of the system. The thicker the acoustic material is, the more effective it will be. Also, creating an air space behind the material will improve its effectiveness. Place as much absorption that is practical at the first reflection points to improve the response of the system.
Bass room modes
If you notice any peaks or dips in the low-frequency response curve of the RTA (20-250 Hz), they are probably caused by room modes. Room modes occur at specific low frequencies that have wavelengths that are equal to or multiples of the dimensions of the listening room.
For example, if the listening room is 4 metres long, there may be a room mode at 43 Hz since its wavelength is about 8 meters. What this means is that for this frequency, the room response will change dramatically depending on the position of the listener and the monitor. You may hear more of this frequency or less of it depending on the listening position in the room. Modes can be formed from all dimensions of the room; length, width, and height so it can get complicated.
Try moving the positions of the monitors and also the listener to see if you can improve the overall bass response. This will take some experimentation time and is often surprising when the best placement is found. Another solution is to place sound absorption designed for low frequencies in the most effective places to reduce the effect of room modes (often in the corners).
Many manufacturers make sound-absorptive devices called bass traps that are designed to be placed in or near corners and will reduce the amount of reflected low-frequency energy in the room. By dampening the resonance of the modes, the low-frequency response of the room may be smoothed out.
When placing bass traps, always check the resulting frequency response curve either with pink noise and an RTA or by listening to your favourite reference material to see how this affects the sound.
Through this process of trial and error, you will arrive at the best position and treatment for your environment. You will get the most out of your Dynaudio Core monitor system, allowing you to create music and sound that translates to as many other listeners as possible. Enjoy!