275a

5

moving coil
diaphragm made of mylar
voice coil with wire
permanent magnet

gutsy, rugged

diaphragm made of thin ribbion
magnet

better low freq response

smooth mellow tone

mylar diaphragm coated in gold or nickel

great transient response

performance data not sound
cables carry no audio

connector is a 5 pin male


one way signal

16 midi channels

can be set to respond to all channels

can be set to play one note or many

in goes to out, out goes to in

goes to next instrument in

in order for computers to send and receive midi, an interface with midi in and out ports is req.

PCI extention slot

connects to usb port

can play different sound per midi channel

add additional in and out ports and provide the solution to latency problems
caused by daisy chain


allow paralell or star config.

latency

a midi device that records, edits

computer based

self-contained

sound source, drum machine, synth w.o an attached controller

voices-how many notes a device can play automatically

wav, aiff, pcm, sd2(sound designer 2)

No data removed

perceptual encoding

removes data that we dont perceive

masking

now recoverable

Digital theater system

3:1 compression ratio

6 channels of 48k/24bit audio

11:1 ratio

MLP

dvd standard

6 channels

developed for video to store more data

earliest video recorders used helical transports

MDM

earliest practical digital recorders used for video

SVHS

8 tracks

Alesis Corp

SVHS tape

40 mins

BRC- big remote control

Hi 8 mm tape 108 min

similar to adat

better syncing capabilities

faster tape transport

editing and random access

does not change original sound

alters original file but is necessary when memory is pushed to limit

edit decision list

cut copy paste
automation
signal processing
fades and crossfades
rythem and pitch perfection

hardware
native
dsp

stand alone all in one systems

emulate tape recorders and mixers

not user configerable

daw

computer based workstations
graphic interface
speed and flexibility
communication w/ file transfer

expandable with PCI cards
midi interface

powered by the host CPU

shift most of the necessary processing to supplementary hardware

audio can be distributed digitally

DSP

by converting electrical eneergy into acoustical energy

electromagnet ( coil of wire wrapped around metal) current through wire magnetizes metal

the cone must vibrate more quickly

low freq

high freq

divide the speakers spectrum into sub ranges and freq bands

the point where audio frequencies are divided into bands

uses capacitors and resistors at high, low, and band pass filters to divide the signal

filters do not eliminate all freq past cutoff

circuit must be able to withstand power of amp

amp must drive whole system

"back-emp" created when signal stops and speakr keeps moving creating a bad current

precedes the amplif. in the signal path

once divided routed to different amps

more effiecient doesnt need much power

less power....vice versa

air cant escape internal air pressure changeing, when driver moves in pressure increases...etc

tighter sound

less bass

because amp has to boost electrical signal to overcome force of air pressure

digital display lines

 DDLs record a sound and at a user defined interval, play or release the signal.
 The combination results in the impression of space, ambience, echoes

 Control that takes the delayed signal and feeds it back into the input of the delay unit.
 You hear the original, the delay and then a delay of the delayed signal.
 The higher you turn the feedback up, the more times the delay is repeated

one discrete repetition
 More than 50ms of delay
 Often referred to as “slapback” delay

 Echo with regeneration

 Some take a mono input, generate two differential (pseudo stereo) outputs

 Delay with multiple stages
 Like multiple play heads on tape delay

 Adjusts the delay time to a musically rhythmic increment by tapping a button

 Originally achieved by recording the same signal to two different tape machines.
 Playback was mixed to a single output with one of the machines slightly delayed by pressure on the supply reel (the flange of the reel).
 Creates deep “swooshing” effect

lfo: Low frequency oscillator that continuously varies the delay time

 Regeneration
 Speed/Rate – speed at which the delay time changes.
 Depth/Width – depth of modulation or delay time change.

 Signal sent through all-pass filter
 Passes all frequencies, but shifts phase of the signal slightly
 Mixing with original creates comb filtering, more gentle than flanger
 LFO modulates “center frequency

 Gives voice or instrument a fuller, stronger sound
 No phase cancellation, instead detuning
 Delay times 15 to 50 milliseconds

 Originally achieved by repeating the performance on a second track.
 Same basic circuit as flanger
 20–50 milliseconds of delay time
 Also incorporates modulation

 Delays are often simple devices that add a single or a few repetitions to a signal.
 Reverbs are complex devices that attempt to recreate an acoustical environment

the sound wave that travels along a straight-line path between the source and the listener

the time delay between the arrival of the direct sound and the arrival of reflected sound

The amount of time it takes for reverb to decay 60 dB

 A microprocessor that simulates the randomness of natural reverb
 Series of digital delay lines (DDLs)
 Allows for user control via a set of adjustable parameters

– Spectrum
– Time
– Dynamic
– Noise

 Limit a signal so that signal is not degraded or equipment is not damaged

– The difference between the lowest and highest levels that an electronic device is capable of handling or that the ear can ear.

120 db

– Electrical current/components
– Tape hiss
– Distortion…tape and electrical component limits

 The difference between the maximum level that can be handled without incurring distortion, and the average operating level

pitch modulation

regeneration

modulation

attack/release
ratio
threshold
input/output signal

front and back

speaker mounted in cabnit with no ports

tighter bass because the cabnit is sealed

3db per surface

every wall increases by 3

Rt=R1+R2+R3

Rt= 1/R1+ 1/R2...

onmidirectional...condensor

super and hyper...condensor mics

figure 8

condensor....transient happens loud and quick

too much bass

12 in or less

ribbon mic

condensor....flattest response

TWICE AS FAR TO GET OMNIDIRECTIONAL

----|___|----

HIGH PASS

BAND PASS

between power amp and speakers

sampling rate- time- freq

quantization- volume- amp

dither

low pass filter set to 20Khz or niquest fred (1/2 sampling rate)

bad doubling

1/2 sampling rate

44.1
1000 Hz
44100

xlr cable, aesebu

8 channels of digital audio

ability to jump from one end of the project to the other by clicking

16

synth w/o keyboard

controller

GM

250 hz

pinna, ear canal, eardrum

hammer, anvil stirrup

noise floor

perceived diff is 10x louder

threshold of hearing

sound pressure level

conductivity

unit of current # of electrons

analogous to light bulb
volt analogous to pressure pump created not the pump itself

no current is flowing

open circuit

when switch is closed it is also a short circuit

we dont know how much current