MUSC1010 – WEEK 8

Sound Radiation and Pro Tools Audio

SOUND RADIATION OF INSTRUMENTS

When setting the microphone position for an instrument or voice it is important to consider its radiation characteristics. If you want to achieve a balanced tone that is representative of normal listening conditions it is important to get the right distance and angle from the sound source. A cello produces a rather complex radiation pattern (see below). The acoustic of the performance venue is crucial for allowing all the different frequencies to reflect and combine. Close micing the instrument may be necessary in some situations, but does not deliver the most tonally balanced recording. EQ would usually be necessary in this instance

Figure 1 – Radiation of a cello. Shaded area represents top 3dB of output for given frequency range. Fletcher and Rossing, The Physics of Sound. Springer 1998

Starting the Pro Tools Audio Assignment

Loading up the Assignment 3 Source File

Because the drive letter may be different when you load up the assignment 3 source file, Pro Tools may prompt you to acknowledge the changed location. If so it will ask if you want to save a detailed report. Choose “NO” and continue.

1. Rename the file and place it in your own folder2. ALL Edit group is active. How does that effect using Solo / Mute, automation, etc..? How can you de-ativate the ALL

edit group?

Two approaches to Assignment 3 Structure;

3. Remove unwanted source music immediately. Then mix and loop. Add other necessary material.4. Place source music on independent tracks. Mix the parts you would like to use. Mute and Hide unused tracks

STEP 1!!!FILE > SAVE SESSION COPY IN…

Auxiliary Tracks are used to

process separate signal buses in Pro

Tools. Auxiliary tracks are created

for various reasons;

Reverbdelay

combined processing (effects) of

instrument groupsvolume adjustments

for instrument groups

To Create a Reverb Auxiliary

Track (BUS)

1. Create and auxiliary track and select BUS 1-2

as the input2. Insert a Reverb plugin

instance3. Add sends on BUS 1-2 to any tracks which you

wish to have reverb. 4. Adjust the send levels

til suitable.

Reverb

The following information relates to the D-Verb plugin and is excerpted from the DigiRack Plug-ins Guide available at the Digidesign website in PDF format

Algorithm

This control selects one of seven reverb algorithms: Hall, Church, Plate, Room 1, Room 2, Ambience, or Nonlinear. Selecting an algorithm changes the preset provided for it. Switching the Size setting changes characteristics of the algorithm that are not altered by adjusting the decay time and other user-adjustable controls. Each of the seven algorithms has a distinctly different character:

Size

The character of the reverberation changes with each of these settings (as does the relative value of the Decay setting). The Size buttons can be used to vary the range of a reverb from large to small.

Diffusion

Diffusion sets the degree to which initial echo density increases over time. High settings resultin high initial build-up of echo density. Low settings cause low initial buildup. This control interacts with the Size and Decay controls to affect the overall reverb density.

DecayDecay controls the rate at which the reverb decays after the original direct signal stops. Thevalue of the Decay setting is affected by the Size and Algorithm controls. This control can be setto infinity on most algorithms for infinite reverb times.

Pre-Delay

Determines the amount of time that elapses between the original audio event and the onset ofreverberation. Under natural conditions, the amount of Pre-Delay depends on the size andconstruction of the acoustic space, and the relative position of the sound source and the listener. Pre-Delay attempts to duplicate this phenomenon and is used to create a sense ofdistance and volume within an acoustic space.

Hi Frequency Cut

Hi Frequency Cut controls the decay characteristic of the high frequency components of thereverb. It acts in conjunction with the Low-Pass Filter control to create the overall high frequency contour of the reverb.

Aligning different audio loops (remixing)

Identify BeatIn order to sequence new material to existing audio it is necessary to create a tempo map based the audio. Do this by placing Bar/Beat Markers in the timeline that coincide with the musical pulse of the audio;

Use the kick drum or other obvious transient to find the beginning of each bar, or every two bars. Place the cursor just in front of the transient and press Ctrl-I. Type in the bar number. Once you have created two or markers Pro Tools automatically calculates the average tempo between the points. Now just ensure that the symbol is active on the transport bar so that the new tempo is obeyed during playback.

The Time TrimmerThe Time Trimmer is used for matching an audio region to the length of another region or tempo grid. You use the Time Trimmer by dragging the region’s start or end point to expand or compress the region.

Elastic AudioYou can also use elastic audio options to conform the tempo of audio clips. You will first need to enable elastic audio;

Choose between polyphonic, rhythmic, monophonic or varispeed elastic audio depending on the nature of the audio track.

…then configure the Elastic Properties for each audio region by right-clicking on the region.