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	WPI Technical Theatre Handbook: Digital Audio Tape (DAT)
	Digital Audio Tape (DAT) A significant advance in tape technology has given the industry the DAT (Digital Audio Tape). DAT addresses many of the problems associated with standard tape, but does not solve all of them. Standard tape employs an analog method of recording. That is to say, at any given time, the voltage coming off of the playback head in a tape deck may be any voltage within a certain range. This voltage directly represents the sound recorded on the tape. With DAT, what is stored on tape is a digital representation of the sound. All that is being read off of the tape are binary data -- ones and zeroes. Digital recording schemes work by sampling (reading) an analog signal many times a second. Each sample is a representation of what the continuous analog wave (the sound) is ``doing'' at a particular time. However, it is not an entirely accurate representation of the sound, as there are a discrete number of representations for each sample. That is to say, where an analog signal can be any value in between two end points, a digital sample can only be one of several values in between those points. DATs sample at either 44.1KHz (44,100 times a second) or 48KHz (48,000 times a second)6.1. DAT decks sample with a 16-bit resolution, meaning 16 individual ones or zeroes are used to represent one sample. This translates to each sample being any of 65,536 values. The faster the sampling rate and more bits of resolution yield a more accurate representation of what's being recorded. It should be noted that no digital recording method is as accurate as analog methods, because digital methods are only approximations of the analog signal. Several advantages make DAT more appealing than standard tape. A scheme of indexing and cueing is included, thus it is fairly easy to cue with DAT. However, seeking between cues is not instantaneous, as the tape must still be physically moved to the proper position. DAT is also relatively free from the noise problems associated with analog tape. Even with DATs advantages, it is still a tape, and thus isn't exceptionally robust. Quality DATs can last a considerable period of time, but when they start to degrade the effects are quite noticable. As the magnetic oxide flakes off of the tape, the DAT deck becomes incapable of reading the data, and produces a noise somewhere in between an explosion and someone scraping their fingernails on a chalkboard. Needless to say, this is less than desirable. This and the problems with cueing make DAT more suited to recording effects and music for a production for playback in some other digital format such as compact disc. Use of information in this document implies understanding and agreement with the copyright and terms of use. Specifically, no warranty is expressed or implied regarding the accuracy of the information contained within. YOU USE THIS INFORMATION AT YOUR OWN RISK. All trademarks are property of their respective owners. You must obtain permission from the author before using the contents of The Handbook for anything other than private use.	Table of Contents [Whole book in PDF 5.3MB] Contents Introduction Goals Sources Methods Conclusions Costumes Introduction Procurement Fabrics Color Patterns Fitting Rehearsal Clothing Design How to Begin Color Practicality Documents The Set Introduction Set Pieces Platforms Flats Stairs Rakes Other Structures Floor Coverings Construction Materials Tools Finishing Painting Types of Paint Mixing Paints Applying Paint Draperies Design How to Begin Documents Computer-Aided Design A Typical Set Construction at WPI Rigging Introduction Common Rigging Hardware Rope Wire Rope Thimbles, Wire Rope Clips, and Swages Shackles, Turnbuckles and Hooks Chain & Rapid Links Slings Fly Methods Non-Counterweighted Pulley Systems Counterweighted Fly Systems Lifts Chain Motors Flying Set Pieces Lighting Introduction Lighting Instruments Scoops Cyclorama Lights Parabolic Reflector Cans Fresnel Spotlights Ellipsoidal Reflector Spotlights Automated Instruments Color Color Theory Primary, Secondary and Complementary Colors of Light Light Mixing Practical Use of Color Glass, Gelatine and Plastics Dichroic Color Filters Patterns Dimmers Dimmer History Cables and Connectors Lighting Boards Control Design Washes Specials Cyclorama Lighting Color Lighting Angle Simulating Exteriors Lighting Design Paperwork Shop Order Instrument Plots Focus Sheets Computer-Aided Lighting Design A Typical Lighting Hang at WPI Audio Introduction Input Microphones Converting Sound to Electricity Directionality Analog Tape Digital Audio Tape (DAT) Compact Disc (CD) Mini-Disc (MD) Digital Samplers Computer Sound Cards Mixing Boards Signal Processing Equipment Equalizers Compressors and Limiters Noise Gates Effects Processors Output Power Amplifiers Speakers Crossovers Cabling and Connectors Line-Level Speaker-Level Automation Design Creating and Obtaining Effects Editing and Processing Effects Designing the Sound System The Input Section Signal Processing The Output Section A Typical Audio Setup at WPI Power Introduction Basic Theory Power Feeds Power Distribution Boxes Power Protection Important Considerations Special Effects Introduction Animated Costuming Smoke and Fog Pyrotechnics Acknowledgements References List of Figures Index About this document ...

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