technical information

These plots are broad-band Energy Time Curves (ETC) plots of a 4" reference loudspeaker with a test microphone placed between the loudspeaker and a reflecting plane. The loudspeaker represents your sound source and the reflecting plane represents a room boundary such as a wall, ceiling or floor. Apart from the intentional reflecting plane, the measurements were conducted in a fully anechoic chamber. The ETC's show the energy in the vertical axis (in dB) vs. time in the horizontal (in milliseconds).

The plots illustrate, in a simple manner, the ModTrap's achieved reduction in potentially destructive first-order reflections. The first plot shows the direct signal arrival at approximately 1 millisecond (roughly 1 foot distance) and the corresponding first-order reflection at approximately 6 ms. The second plot is an identical measurement with a small ModTrap placed between the microphone and the reflecting plane. (See images of test setup. ) In the second plot the first-order reflection is reduced by more than 25 dB.

So what? Here's what: While many absorptive materials will provide a substantial reduction in reflections, the ModTrap's unique design allows for very simple placement of the right amount of control just where you need it, while retaining the desired degree of 'room' sound provided by diffuse, late-arriving reflections and reverberation provided by your studio.

The following plots demonstrate the affect the early refection can have on the frequency response of the sound you are recording. The plots show the frequency response of the same 4" loudspeaker with and without the ModTrap in place. Notice the jagged appearance of the upper plot. This is the comb filtering of the frequency response caused by the undesired reflection. In our example the comb filtering, while present throughout the entire frequency range, is particularly deep at the upper octave. This demonstrates why the ModTrap is so effective in "tightening up" sounds when placed between a microphone and a wall, floor or ceiling.