AUDIO
INTO THE MATRIX | Jeff Hawley
On a recent trip to the thrift store to expand my collection of vintage western pearl snap button shirts , I came across a classic rack mount mixer similar to the classic Shure M67 . The design and overall format is just about as simple as you get with an audio mixing device , each input outfitted with a big VOLUME knob and an in-out switch for a lo-cut filter . No additional equalization or compression or other fanciness . It did get me thinking about the way design seems to go in circles , though . Just like worn cowboy shirts , we ’ ve seen a return to the form factor of the simple and dedicated ‘ set it and forget it ’ sort of mixing tools for the install market , albeit with a more flexible , digital and networked twist . Those of us who grew up behind giant analog consoles might not think of these simple rack units as being a ‘ real ’ mixer , but the power and usefulness of a dedicated audio matrix is undeniable .
An Allen & Heath AHM-64 matrix and AHM System Manager software . Program as needed to tackle sound management , paging , audio distribution , conferencing and speaker processing roles .
What is old is new again . Deliver simple controls to non-technical users via a digital audio matrix — just like the good ‘ ol days .
Sometimes referred to as a ‘ DSP ’ ( digital signal processor ), audio matrixes ( or matrices ) are a sort of distilling down of the functions of what the more obvious ‘ mixer shaped objects ’ can do . Perhaps it is best to imagine the usual medium-sized church audio system and break it down into its component functions to best illustrate the point here . We have the mixer control surface that allows for adjustment of various system settings in a tactile manner — faders , knobs , screens , etc . We also have some sort of stage box or dedicated component for getting audio in and out of the system . Lastly , we have some ( likely digital ) processing ‘ hub ’ that is managing those inputs and outputs and passing along the changes and adjustments that we are making via the various control surfaces . Most audio matrix devices are designed to excel at this task as a sort of ‘ brain ’ without an obvious surface or a phalanx of XLR inputs and outputs at hand .
Why might we want to consider the use of a matrix ? I think the old adage ‘ do one thing and do it well ’ is fitting in this case . That ‘ one thing ’ for an audio matrix is signal flow . An audio matrix allows for very fine-tuned audio signal configuration , often well beyond the level of detail that a more ‘ mixer shaped ’ console can achieve . Want to create a system to easily route a small number of inputs to a large number of outputs or zones , complete with integrated audio file playback ? No problem . Need to set up a single button push to completely flip a user-friendly remote audio control screen to a totally different set of inputs with priority ducking channels set ? All good . Want to enable acoustic echo cancellation in a conference room to better manage Zoom call audio — and have non-technical staff be able to make it all work without an audio engineer around ? Yep , got you covered .
Rather than present a fixed layout of channel strips and output buses and a set way of interacting ( as a more ‘ mixer shaped ’ console would ), our friend the audio matrix starts out with much more of a blank slate . A system
A custom control touch interface can be designed to be as simple or as complex as needed .
designer ( that ’ s you !) will generally begin by firing up software on your Mac or PC and connecting to the audio matrix device . At this point , the view may be more akin to a graphic or CAD sort of program with connected graphic blocks and routing diagrams than what you would generally see on your FOH mixing console . But you ’ ll also recognize a collection