Gain staging/ Interconnectivity

Question 1

define noise floor

Answer 1

the point at which a signal is so low hiss and system noise can be heard

Question 2

define clipping point

Answer 2

when the signal is too high that it cannot be accomodate by the signal resulting in distortion

Question 3

define signal to noise ratio S/N

Answer 3

the level of noise in recording in relation to usable signal

Question 4

define headroom

Answer 4

the range between operating level and the systems clipping point

Question 5

define gain staging

Answer 5

recording hot enough to avoid excess levels of unwanted noise, but also having enough headroom to avoid distortion

Question 6

what are the commonly used meters

Answer 6

Analogue peak

VU

Analogue dBu

Digital peak

Digital RMS

Question 7

difference between analoge and digital metering

Answer 7

digital meters zero is the max operating level, any further then distortion occurs

analogue zero is the optimum level, and you can go above this without distortion to a point, and when distortion occurs it can be pleasing

Question 8

describe a VU meter

Answer 8

designed to give an indication of average volume rather than peak level, slow response time approx 300ms means meters cannot show peak level.

Question 9

describe the dBu meter

Answer 9

referecned using an LED display. averaging meter that does not show peak values.

Question 10

describe the PPM meter

Answer 10

analogue meter shows peak levels in analogue domain. hybrid meaning it shows peak levels and averaged levels

Question 11

DbV meter

Answer 11

a second seperate operating level devised for semi pro or consumer equipment, based around an operating level of 1.0 vrms which is know as dBV

Question 12

what are the different units and their levels in vrms

Answer 12

+4dBu 1.227 Vrms
0dBV 1.0 Vrms
0dBu 0.775 Vrms
-10dBV 0.316Vrms

Question 13

what do pro level analogue operating levels operate at

Answer 13

+4dBu, which translates as a nominal voltage of 1.227 Vrms, which is called line level

Question 14

what consumer gear operating levels operate at

Answer 14

-10dBV, meaning a nominal operating voltage of 0.316 Vrms

Question 15

what are the acceptable levels in analogue

Answer 15

any peaks rising up to 8dB above 0VU (+rdBu) are acceptable

peaks above 12dBu start to distort

undesirable clopping occurs around +18dBu or +24 dBu on higher end systems

Question 16

describe dBFS

Answer 16

digital clipping is so undesirable that meters had to show peak level rather than average in the digital domain. This lead to dBFS, where 0dBFS is the highest possible figure in digital domain. Anything above that is a clip

Question 17

what level should your peak values be in a DAW compared to the analogue domain

Answer 17

between -6dBFS and -12dBFS, depending on the transient nature of the material

Question 18

what are the recommended digital levels for engineers to calibrate analogue VU meters to

Answer 18

• 18dBFS in the UK

- 20dBFS in america

Question 19

what is the standard monitor calibration level in the film and television industry

Answer 19

0 VU equals 83 dB SPL

Question 20

what is the K system

Answer 20

it is a calibrating listening level system. designed to allow you to return to a calibrated listening level that is a compromise between the point at which your ears have the flattest response and a comfortable listening level

Question 21

what are the three tiers of the k system and what are they best used for

Answer 21

K20 = for music with the most dynamics such as large theatres (20dB headroom)

K14 = standard for pop and rock music (14dB headroom)

K12 = for programmes dedicated for tv and radio broadcast (12dB of headroom)

Question 22

what should the 0 in the k systems be equal to

Answer 22

83 bDC SPL with pink noise on each k/rms meter