PART 1 STUDY GUIDE MMGT 96

Directional Response: refers to its sensitivity (output level) at various angles of incidence with respect to the front (on-axis) of the microphone. Frequency over 360.

Omnidirection polar response: is a pressure-operated device that's responsive to sounds that emanate from all directions.

Bidirectional: figure 8 pattern.older ribbons use this. 

Frequency-response curve: the measurement of its output over the audible frequency range whendriven by a constant on axis input signal. 20-20000Hz RANGE. 

A mic that responds equally to all frequencies= flat frequency response. Others= high, middle low end response

Proximity effect: low frequency effect for directional mics. causes an increase in bass response wheneve a di mic is brought 1ft of sound source. increases as distance decreases. IN VOCALS! 

To get rid of p. effect: greater for bidirect than for cardiods, a low-frequency switch on body could be used. OR Replace directional mic with omni. 

Transient Response: how quickly a mic's diaphragm will reach when it is hit by an acoustic wavefront

Phantom power: only condensor mics. powered straight from the console. 

Distant miking: used to pickup large instrument ensembles. mainly relies on acoustic environment for sound. 

Close microphone placement:  positioned 1-3 feet from instrument. if done right, it creates a tight, present sound quality and effectively excludes the acoustic environment. only desired on axis sound will be recorded.

Leakage: when other instrument is captured through microphone.

How to avoid leakage: place the mics closer to their respective instrumentsplace an acoustic barrier between 2 instrumentsuse directional micsspread the instruments farther apart

Distance rule: for every unit of distance between a mic and its source a nearby mic should be seperated by at least three times that distance

Tonal balance: timbre

Accent Mic placement: should sound natural to the overall pickup. should only ad presence to a solo passage

Ambient miking: places the pickup at such a distance that the reverberant or room sound is more promient that the direct signal. OFTEN: a cardiod stereo mic pair or crossed figure 8 pair

Spaced Pair: can be placed in front of instrument(s) to obtain a stereo image.  2 mics of the same 2-30 feet apart.

X/Y stereo miking: 2 directional microphones of the same are placed with their grills as close as possible, no touching. and facing at angles 90-135. use cardiod mics. 

M/S: (midside), like XY but requires use of an external transformer, active matrix, or software plug in. M=CARDIOD S=  FIGURE 8 PATTERN

Decca Tree: 3 omnidirect mics,

Direct Box: direct injection

1.Natural, smooth tone quality 2.Bright, present tone quality 3.Extended lows 4.Extended highs (detailed sound) 5.Increased ‘‘edge’’ or mid-range detail 6.Extra ruggedness 7.Boosted bass at close working distances 8.Flat bass response up close 9.Reduced leakage, feedback, and room acoustics 10.Enhanced pickup of room acoustics 11.Reduced handling noise 12.Reduced breath popping 13.Distortion-free pickup of very loudsounds 14.Noise-free pickup of quiet sounds

1.Flat frequency response     2.Rising frequency response 3.Dynamic or condenser with extended low-frequency response 4.Condenser 5.Dynamic      6. Dynamic or modern ribbon/condenser        7.Directional microphone 8.Omnidirectional microphone 9.Directional microphone, or omnidirectional microphone at close working distances     10.Place microphone or stereo pair at greater working distances 11.Omnidirectional, vocal microphone, or directional microphone with shock mount 12.Omnidirectional or directional microphone with pop filter 13.Dynamic or condenser with high maximum SPL rating 14.Condenser with low self-noise and high sensitivity

Toward the end of the 1970s, the process of converting analogue signal into digital information, known as digitizing, was very rare.  Most professional recording studios were completely analogue, using large reels of  magnetic tape for sound recording.  Although there were some digital processing and recording devices available, these units were extremely expensive, not very flexible and in some cases, sounded bad.  The early digital signal processors were eight-bit with a grainy sound.  Digital multi-track recorders were very large, tape based offering little in the way of digital editing or signal processing. In the 1980s, as micro processor technology began to develop and as external memory storage moved from digital tape to floppy or hard-disk, digital audio technology became more affordable. By 1990, hard-disk recording systems, like Digidesign’s “Audio Media” system with “Sound Designer” software, allowed users to record and graphically edit 2-tracks of 16-bit digital audio recorded onto a SCSI hard-disk drive using an Apple computer.

In 1992, a company named Alesis introduced the first low-cost digital audio multi-track tape machine using SVHS tape as it’s recording/storage medium.  The Alesis ADAT system boasted eight tracks of 16 bit digital audio at 48kHz with the ability of chaining together 15 additional ADAT units, giving a grand total of 128 simultaneous tracks.  Because hard-disk space was still quite costly (roughly one dollar per MB) with the process of digital recording needing lots of disk space (10MBs per stereo minute), the Alesis 1.6 gigabit 40 minute, 8-track SVHS tape was very economically attractive at $20.00 per tape. Another popular digital audio recording device and format of the time was the 2-track Digital Audio Tape or DAT machine.  These machines were used primarily for stereo recording and mix-down.  The DAT machine used a DAT tape that was similar to the ADAT tape, but, much, much smaller in size.

Both the 8-track ADAT and the 2-track DAT machine used an angled/elliptical rotary cylinder head, similar in fashion to the VHS video tape machine head.  The only real difference, beside the speed of the tape transport, ADAT and DAT machines striped digital audio data instead of analogue video frames. Around the same time as the development of the ADAT system, Digidesign released what is now its world famous PRO TOOLS recording and mastering hardware and software system.  Designed around the Macintosh platform, it was comprised of an external rack-mounted analogue to digital and digital to analogue converter (A/D and D/A) interface that was wired directly to the computer via a “New Bus” slot card.  PRO TOOLS, the name of the software, is a powerful graphic interface that provides multi-track recording, digital signal processing and editing, MIDI data sequencing and real-time control automation for mix-down.

Today, the digital audio tape machine has been replaced by hard-disk based digital audio multi-track workstations.  These devices are all-in-one recording, processing and mixing systems using large hard-disk drives for recording and a built-in CDRW for burning the final 2-track product. Now that the cost for hard-disk storage has dropped in price (roughly one dollar per 10GB of disk space) digital audio workstation sand computer based recording and MIDI sequencing software systems dominate the world of audio recording and music production.   Although hard-disk recording dominates the industry, it is important to understand the development that digital audio has gone through up to this point. Three Types of Digital Recording Systems 1) Recording using Digital Audio Tape 2) Recording using a RAM-based system 3) Recording using a Hard-disk Drive

Trumpet: best to place a mic slightly off the bell's center at a distance of 1  ft or more. Trombone: at 2-12 inches,the player should play slightly to the side.Tuba: a range of 2 ft or more, slightly off axis bellFrench Horn: omni or bi pickup bw the rear wall

Acoustic Guitar: condensor mics are preferred. place mic to center of the bridge, at a distance bw 6 in to 12 in.Sorround guitar: use XY model.Electric guitar: use cardiod dynamic.Bass Guitar: large diaphragm dynamic mic, or DI box

A day in the life: compressor on lennons voice, delay tape delay with repeats, EQ on lennons voice

castles made of sand: delay on guitar, compressor

Somethings coming: chorual modulation, 

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Digital Audio Technology

DAT PT 2