This is a transcription of my 40-minute presentation on low frequency control during the 59th AES conference on sound reinforcement in Montreal. Needless to say that 40 minutes is barely enough time to scratch the surface on such an involved topic. I therefore decided to focus on establishing the need for low frequency control, something I felt I could do within 40 minutes, and not attempt to cover each intricacy of the various solutions at our disposal.
I start by briefly refreshing on summation to make sure everybody is on the same page. Next we’ll meet the player commonly referred to as a subwoofer. We’ll continue with establishing the need for low frequency control, the essence of this introduction and finally have a look at current typical solutions.
A while ago I was able to attend the very first Danley demo hosted by Firm4 in cooperation with RF Shows in this small corner of the world. Having read numerous animated threads at the ProSoundWeb forum about the distinguishing qualities of these products, I was very eager to finally experience Danley for myself. It was a very inspiring phenomenon, so much that I intended on doing my own production within two weeks time. Keep on reading for full disclosure on a very remarkable event. The premiere of Danley products in a theatrical production in The Netherlands.
This article focuses on the consequences of introducing an electronic level offset between sources in a 2-element cardioid configuration in an attempt to maximize cancellation.
"Smoothing is essentially another type of averaging that is available only for Transfer Function displays (Phase or Magnitude). This feature helps to reduce "jagginess" on transfer function traces and can make trends in the frequency response of the system under test easier to see. On a smoothed transfer function trace, each data point is averaged together with some number of the immediately adjacent points on either side."1
Find out how this post-processing feature alters accurate data and provides a misleading frequency response or trend.