MTD2 class 6

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In class

  • Transducers/Microphones
  • Connectors
  • Audio Levels
  • DAT Demo
  • Scan Demo

Audio Levels

Good Level Audio Levels


  • Microphone level - The level (or voltage) of signal generated by a microphone. Typically around 2 millivolts. Compare this with the two normal line levels
  • Phono Level - little larger than mic level also has equalization based on standardized RIAA curve. use phono input a line
  • Line Level - . There is an international standard for the level of inputs; it is around -10dBV(.316V) for semi-pro equipment, and about +4dBu(1.228V) for "pro" equipment. Line level outputs can come from tape decks, CD players, tuners, DAT decks, effects, etc. (1.228V:+4dBu and .316V:-10dBV)
  • Speaker level - higher voltages for speakers

Audio Level Links

Audio connectors

  • 1/8" (3.5mm) Connectors Jack Plug Connectors Tip ring sleeve Connectors Eighth.jpg mono Connectors Eighth mono.jpg stereo Connectors Eighth st.jpg
  • 1/4"(6.35mm) Connectors Connectors QuarterBend.jpg Connectors Quarter.jpg
  • Banana Plugs Connectors Bannana.jpg
  • Binding Posts Bayonet Neill-Concelman/British Naval Connector type of signal varies or BNC Connectors Bnc.jpg
  • RCA-Type video left audio right audio Connectors Rca y.jpg Connectors Rca bl.jpg Connectors Rca w.jpg
  • XLR Microphone XLR Connectors Xlr.gif
  • TOSLink http://en.wikipedia.org/wiki/TOSLINK TOSLINK.jpg

Bluffers guide to WIRES AND CONNECTORS

Transducers

Transducer = a device that converts one type of energy to another. A microphone converts acoustic energy to electrical energy. A speaker converts electrical energy to acoustical energy. They are both transducers.

Microphones

Microphones

good reading Audio Technica Guide to Microphones

Types of microphones

  1. Dynamic
  2. Condenser
  3. Ribbon
  4. piezo electric (contact Mic)

other (Stereo, binaural, PZM- pressure zone microphone http://www.crownaudio.com/mics.htm)

Ribbon Mic

The first type of mic was a Ribbn Microphone. Basically a light wieght ribbon that conducts electricity the is suspened in between two magnets. Older ribbon mics usally have a reduced frequency response.

http://www.coutant.org/ribbons.html

Dynamic Mics

A light weight diaphragm is connected to a coil that is suspended between a magnet.

404px-SM57&Beta57.JPG

Condenser Microphone

A very light weight diaphragm is suspended in front of an electrically charged back plate. The two plates basically act as an open air capacitor. As the air pressure changed the distance between the plated the capacitance between the plates also changes.

Condenser microphones need Phantom Power to work.

399px-Microphone U87.jpg

Our stereo mic: Audio Technica AT825 [1]

Microphone Comparison

Parameter Dynamic Condenser Ribbon
Frequency Response Good Best Worst
Dynamic Range Good Good Worst
Durability Best Good Worst


Proximity Effect

The frequency response of a directional microphone changes as it it brought close to a source. The bass response increases.

http://en.wikipedia.org/wiki/Proximity_Effect#In_audio

http://www.csun.edu/~record/prox/prox.html

Polar Patterns

http://en.wikipedia.org/wiki/Microphones#Microphone_polar_patterns

  • Omni-directional - all directions
omnidirectional
  • Bi-directional (figure 8)- front and back rejects on the side
Bi-directional (figure 8)
  • Uni-directional - one direction
  • Cardioid - one direction with lobe
Cardioid
  • Hypercardiod - really one direction with lobe
hyper cardioid

http://www.mikelights.com/micpolar.htmlALC Microphone Directionality Some pictures

http://www.csun.edu/~record/polar.html Some more Pictures

Stereo Mic Techniques

Spaced Omni's - two spaces Omni mics

XY - Coincident cardioids at 90 degrees

ORTF (Office de Radiodiffusion -- Television Francaise)110 degrees 17cm apart - Near Coincident Pair About.com Microphones Part 1

Dat Heads mic-FAQ.txt

Audio Levels

Good Level Audio Levels


  • Microphone level - The level (or voltage) of signal generated by a microphone. Typically around 2 millivolts. Compare this with the two normal line levels
  • Phono Level - little larger than mic level also has equalization based on standardized RIAA curve. use phono input a line
  • Line Level - . There is an international standard for the level of inputs; it is around -10dBV(.316V) for semi-pro equipment, and about +4dBu(1.228V) for "pro" equipment. Line level outputs can come from tape decks, CD players, tuners, DAT decks, effects, etc. (1.228V:+4dBu and .316V:-10dBV)
  • Speaker level - higher voltages for speakers

Audio Level Links

Template:Audio Levels

Scanners

Image Scanner via wikipedia

How Stuff Works Scanners

An image scanner is an input device that uses a CCD to obtain an image.

Modern flat bed scanner typically scan 24 bit RBG color. A scanners resolution is measured in pixels per inch or ppi knows as dots per inch when displayed on a computer monitor. Most computer modern operating systems display 72 or 96 dpi.

Many scanner can scan up to 300 dpi. Really nice drum scanners can scan up 14,000 dpi.

Since we will be displaying or final movies on a computer screen it is fine to scan @ 72 dpi.

Scan, color correct, and crop boards

Scan, color correct, and crop boards demo

  • Scan borads into Photoshop/Gimp
  • Use Photoshop/Gimpto correct color (we don't want color just rclean black and white)
  • Use Photoshop/Gimpto crop frames to correct size and aspect ratio
  • Save as a series of uncompressed images

In Class Articulate Cuts from storyboards what motivates each cut

  • What visual changes are there in the scene?
  • What audible changes are there?
  • What is the time reference?


Homework

Read Chapter 2 in Sound Design for IM

Scan, color correct, and crop boards

Start Audio Search

  • Make a list of all the effect you will need for you animation
  • Start to search library/web/record for sound effects

Quiz 2 next week MTD2 Quiz 2 Review


THIRTEEN WAYS OF LOOKING AT A BLACKBIRD