FRONT OF HOUSE
THE LIMITING FACTOR | Kent Morris
When we speak of an amazing piece of techno wizardry , we often use terms such as “ capable of 144 inputs ” and “ less than 2mS of latency ” with pride in our voice , but the fact remains these are actually negative notes , not positive ones . Why does the console not have 145 inputs and why can ’ t the processor do its work with 1mS of latency ? For all our advancements , we still contend with limiting factors at every turn . On the other hand , guard rails are a limiting factor with life-saving benefits , meaning limits can be a method of resolving the conflict of what can be done into what can be done within this situation .
Capacity denotes a functional standard , such as “ one U . S . gallon ” which gives the user an idea of how it compares to similar items using a commonly accepted measurement . However , the standard must be verifiable and widely accepted to be valid . In audio , clear analog specifications of yore have given way to veiled digital specs with little oversight from government entities . In the 1970 ’ s , a home stereo receiver with 100 watts per channel carried a stipulation of RMS ( Root Mean Square ) methodology , 8 Ohm impedance , its THD ( Total Harmonic Distortion ) and frequency response range across the measurement . Today , a manufacturer is free to advertise a $ 299 plastic powered speaker as capable of outputting 2500 watts , an absurd statement from any perspective . Thus , the onus is on the consumer to evaluate all claims from manufacturers , especially those of lesser reputation .
The first lesson on capacity is to filter all claims through common sense . If a speaker from
Brand A is $ 299 and spouts a 2500 watt rating , while Brands B and C sell for $ 399 and $ 499 respectively and note their power as 450 watts and 500 watts , it means Brand A either has magic inside the box , knows a secret formula for power or is lying . Since there is no such thing as magic and all speaker brands use commonly sourced materials , Brand A is clearly being deceitful .
Once the actual capacity of the product is known , decisions can be made how best to use it within the audio system . For instance , a lower quality wireless mic system with a plastic body and preset frequency selection should never be used on the speaking pastor ’ s mic , but it could be used as a handy talkback mic for the MD ( Music Director ) to speak to the band during rehearsal without everyone having to take out their ear monitors to hear . Additionally , a lowcost passive direct box should be assigned to the acoustic rhythm guitar the worship leader uses more as a prop than an instrument , leaving the nice Radial DI free to connect the dedicated acoustic player ’ s instrument to the sound system .
For churches blessed with live choirs , the limiting factor is always gain before feedback of the choir mics in the sanctuary . Typically , the choir ’ s acoustic output pales in comparison to the drums and cymbals and will roar into feedback when the levels are pushed in an attempt to bring the choir above the din of musical instruments . There are three steps to maximizing the output . First , put the mics in the right place . Choir mics should be about two feet in front of and above the choir . They
should be spread apart enough to prevent pick up by more than one mic and they should be oriented to avoid guitar amps , floor monitors and HVAC noise . Second , use appropriate mics . Choir mics need to be condensers with high output and a response tailored to the sung word . Third , focus the EQ on vocals while ignoring everything else . Start by high-passing the channels at 150-200Hz and low-passing at 10-12KHz . Next , pull out energy of non-voices by sweeping from low to high frequencies with the gain raised and listening on headphones during rehearsal to pinpoint the worst offenders and then changing the boost into a cut .
For churches running mains and monitors from the same desk , use the iPad remote for monitors after dialing in a rough mix on the mains at the console . The idea here is to use the natural energy in the room which reaches the stage as a starting point for the monitor mix instead of starting with monitors and then adding mains . This process works even with in-ear based stages because lower frequencies permeate the ears and many vocalists remove one monitor during the service , despite being admonished to not do so .
Limited capacity doesn ’ t mean limited performance if common sense is used when purchasing gear , lower quality products are assigned appropriately and choir mics are dialed in correctly .
Kent Morris Kent is a 40-year veteran of the AVL arena driven by passion for excellence tempered by the knowledge digital is a temporary state .