Recording - November 2012 - 36

Over the last two months this column has investigated the ins and outs of signal flow, including the role of microphone preamps, variations in console design, audio recorder monitor modes, and how consoles and recorders are integrated in modern DAWs. This month the discussion continues with a look at monitor-mix creation, auxiliary sends, and DAW latency issues. If you find the topic of signal flow challenging (and believe me, most recordists do), you might want to visit the previous two installments of Fundamentals to refresh your knowledge before continuing on.

control room mix. In this situation everyone listens to the same thing and the engineer needs only to make one mix. Although easy to manage, the single-mix approach has serious disadvantages. For one thing, the engineer cannot turn sources on or off in investigation of technical issues, as drastic changes affect the performers listening in the studio. Secondly, musicians usually want to hear a mix completely different than what the engineer prefers in the control room. To make matters worse, most musicians have their own individual needs: guitar players want more guitar, bassists want more bass, and vocalists want more vocal. The necessity for multiple mixes always arises whenever multiple musicians record simultaneously. Imagine this scenario: You are an engineer, tracking a three-piece rock band with drums, bass, and guitar. The drummer, wanting to ensure the songs stay locked in tempo, chooses to use a click track. The click, which is simply a metronome, blasts a percussive sound into the drummer’s cans (headphones), keeping time steady. The guitarist and bassist, on the other hand, have no desire to hear the click. To accommodate these requests, you the engineer must provide three separate monitor mixes: one for the drummer with click, a second without click for the two other band members, and a third for yourself in the control room so you can independently adjust listening levels without bothering the musicians. By Eric Ferguson

Chapter 11: Signal Flow Part 3
In last month’s issue, special attention was paid to the two audio paths that exist when recording. The first is the record path and it contains everything encountered between the sound source and recorder. The second is the monitor path, and it entails everything between the recorder and our ears. While implementation of these two paths varies greatly among different consoles and DAWs, the golden rule of signal flow must be followed: when recording, engineers and musicians should always listen to the output of the recorder. Monitoring should never be sourced off the record path. This concept can be restated in a different manner: the recording level of each individual source is set in the record path, but the listening level of each source is set in the monitor path. Control room and headphone mixes A control-room monitor mix allows the engineer and other observers to hear all sources being recorded in a musically appropriate balance. To make a mix, the engineer adjusts each track’s individual listening level with some sort of monitor-path loudness control, such as on onscreen fader in a DAW, or a hardware fader or a rotary pot on a console. For tracking dates that involve both a separate producer and a full-sized console, the engineer might set up a raw balance and then hand the monitor mix over to the producer for moment-to-moment adjustments. Regardless of who does what, a control-room mix allows observers to carefully listen for technical and musical hiccups. In addition to the control-room mix, one or more other mixes might also be required to feed musicians’ headphones. In simple sessions, such as a single vocal overdub, the easiest solution is to source the headphone amplifiers off the
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RECORDING November 2012

Aux sends and headphones So how do you make three independent mixes? While fancy solutions exist, the tried-andtrue method is to use console or DAW auxiliary sends. Aux sends are buses, separate paths on which a signal from any console channel can travel upon, mix with signals from other channels, and then connect to a destination such as an effects processor or headphone amplifier. Recording consoles typically offer between two and sixteen auxes, with eight a common configuration. Typically each aux has its own perchannel level control, so an eight aux, 24-channel desk can have as many as 192 auxiliary send knobs present on its surface! For the above rock-band example, you the engineer need to make three separate mixes. The mix required for yourself in the control room is easy, and all you must do is adjust the main monitor path level control on each channel. For the two headphone mixes, aux sends can be used. Since most musicians prefer to listen in stereo (with sound sources panned across the stereo field in their headphones), two aux sends per mix are required—one for left and one for right. On

Recording - November 2012

Table of Contents for the Digital Edition of Recording - November 2012