DIGITAL SOUND I Topical Outline, Summer 2010

I. AUDIO THEORY

Analog concepts Overview, frequency/amplitude general description of audio phenomena, cyclic nature of sound in context of world. Mapping sound to 2 dimensions, understanding wave shape. General working definition of ‘ sound ’ : ‘ perception of energy transmission through a medium via the ears ’ Measurement of frequency & amplitude, harmonics and Fourier 1-1

Digital concepts understanding digitizing: sample/hold, clocks, samples, bit depth, SR, file types Nyquist frequency: SR/2, why? How does bitdepth relate to s/n ratio File headers Meta data 1-2

II. CONNECTIONS/CABLES

Unbalanced: RCA BNC 1/4” ‘phone’ (TS), 1/8” ‘mini’ (TS) Balanced XLR 1/4” ‘phone’ (TRS), 1/8” ‘mini (TRS) Note: TRS can be used either as a balanced mono or an unbalanced stereo connector, depending on the device. Pin blocks 2-1

Analog concepts concept of balanced/unbalanced Signal path: process of transduction from source through storage to destination 2-2

Digital concepts digital interfaces: AES/EBU, S/PDIF. SDI AES: Audio Engineering Society: ‘Pro’ S/PDIF: Sony/Phillips Digital Interface Format: ‘consumer’ AES uses XLR connectors S/PDIF typically uses RCA, can also use fiber optics SDI: Serial Digital Interface Most recent, can transmit HD, SD video and audio on one BNC connector, very versatile. 2-3

III. MICROPHONES

Analog concepts Principles pickup patterns omnidirectional unidirectional bidirectional cardioid supercardioid (shotgun) hypercardioid PZM lavalier 3-1

MICROPHONES, cont. Impedances Lo Z Hi Z Dynamic vs. condensor Phantom Power 3-2

Digital concepts USB mics, USB & FW digital interfaces Digidesign M-Audio Mackie Metric Halo (ad infinitum) FW 400, 800, eSATA, optical 3-3

IV. RECORDING BASICS

Analog concepts getting the best recording level setting ('0' level) Tools (scopes, tone generators etc.) Digital concepts recording via external devices Zoom H2, H4; Marantz; Tascam dvcam caveats Optimum settings 4-1

recording via cpu Audacity (free download) Sound Track Pro More full featured, bundled with Logic Pro Tools Most market share, always tied to hardware At least 10 equally powerful apps on the market, pick based on your UI prefs and feature set. stp 4-2

V. MIXERS & OUTBOARD GEAR

Mixers: Many in, few out Input stage Output stage Aux busses Getting the right levels Mic/line Analog concepts 5-1

Digital concepts digital mixers flying faders midi control virtual busses digital i/o control surfaces 5-2

VI. AUDIO EDITING

Analog concepts brief history/comparison of old vs new techniques Tape-based editing, splicing Digital concepts Organizing assets Projects vs. files Destructive vs. non-destructive Playlists Audacity Soundtrack Pro 6-1

audacity Free! Primarily for destructive editing Some multitrack capability Uses ‘session/export’ model 6-2

Soundtrack Pro Not free! (great student price though) Comes bundled with Logic Studio Full featured destructive editing 6-3

VII. MIDTERM create a 2 minute digital file that involves sound you've recorded and edited. Proper attention should be paid to sound quality, pleasing use of fades, clean endings and transitions

VIII. EQ & CRUCIAL DSP TECHNIQUES

harmonics review types of filters low pass (LPF) hipass (HPF) bandpass (BPF) band reject (BRF) peak/notch lo shelf hi shelf resonance (Q) Analog concepts 8-1

digital eq, filters Broadband Noise Reduction exercise: make a recorded voice sound like telephone. Then improve quality of a telephone recording. Digital concepts 8-2

IX. DSP FX TECHNIQUES

types of fx Reverb Delay Chorus Flange Phase shift Ring modulation Real time vs. non real time, advantages/disadvantages 9-1

DIGITAL Digital examples of each fx type Survey of available fx in Ableton, Logic, Soundtrack, Audacity 9-2

X. MIDI

brief overview of midi, historical, hardware, spec. Reason for midi Numerous digital synths, many manufacturers Need for open source communication protocol Most successful cross platform language ever developed (imo) 10-1

external synths Advantages: work as stand alone devices dedicated soundmaking hardware Disadvantages: can get kludgy limited upgrades 10-2

Software synths Advantages: Integrated into operating system Only limited by cpu power/memory High upgrade capability Infinite presets Disadvantages: has to share system resources tied to cpu, no stand alone no dedicated sound engine 10-3

sequencing Ableton Best suited for live, interactive Extensive softsynth library Flexible fx chaining Logic Best for sequencing steeper learning curve even bigger library very extensible software synths 10-4

XI. MAXMSP, Supercollider etc.

Max/MSP/Jitter Created as an alternative to the sequencer approach to midi Fully interactive and extensible Not 100% open source now integrated fully into Ableton MSP: added DSP capability to Max interface Jitter: added realtime video processing capability to Max interface 11-1

Supercollider Created by James McCartney Fully open source Steep learning curve, limited UI (but not that limited once you know what you’re doing) Superior sound quality to MSP One of many line-code based DSP packages (Csound, RTCMix, Chuck, Jsyn) 11-2

XII. FINAL A piece (no more than 5 min. necessary) showing application of principes learned, including live recording, audio enhancement, use of FX, multitrack timeline, etc.