If there is perhaps more than just one resonance, and all of them close to
one another (in the example above in a room of 4.5 x 5 x 2.5 metres, there
are multiples of frequencies around 35 Hz and 80 Hz), it is obvious to soften
That's exactly what a digital sound processor (DSP) does. Sitronik or Audaphon also supplies
a software package to adjust the frequency response in an easy way:
Picture 1: tuned frequency response for a room of 5 x 4.5
x 2.5 m.
In picture 1 there is a flap for the subwoofer (there is also one for the
left and the right amplifier channel, if you want to use them). The adjustments
were chosen as follows:
The value Q describes how steep a cut-off is.
A small value Q=1 (the green curve pictured left)
bends the frequency response gently,
a Q=5 (the blue curve pictured left) generates a steep curve.
Using the three equalisers with nine parameters, all required frequency responses
up to +/-6dB may be selected. Experience shows that bigger deviations are
most the time not useful (also filters that are too steep), since the overall
sound is affected.
It's, however, a lot of fun to reduce the resonance of satellite speakers
like the full range Ciare CH 250 or a satellite speaker that overdoes it.
Using the buttons E and S, adjustments may be transferred to or from the
Examples Of Us
What is DSP?
to Hypex Fusion amplifier modules