Gain staging/ Interconnectivity Flashcards
define noise floor
the point at which a signal is so low hiss and system noise can be heard
define clipping point
when the signal is too high that it cannot be accomodate by the signal resulting in distortion
define signal to noise ratio S/N
the level of noise in recording in relation to usable signal
define headroom
the range between operating level and the systems clipping point
define gain staging
recording hot enough to avoid excess levels of unwanted noise, but also having enough headroom to avoid distortion
what are the commonly used meters
Analogue peak
VU
Analogue dBu
Digital peak
Digital RMS
difference between analoge and digital metering
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
describe a VU meter
designed to give an indication of average volume rather than peak level, slow response time approx 300ms means meters cannot show peak level.
describe the dBu meter
referecned using an LED display. averaging meter that does not show peak values.
describe the PPM meter
analogue meter shows peak levels in analogue domain. hybrid meaning it shows peak levels and averaged levels
DbV meter
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
what are the different units and their levels in vrms
+4dBu 1.227 Vrms
0dBV 1.0 Vrms
0dBu 0.775 Vrms
-10dBV 0.316Vrms
what do pro level analogue operating levels operate at
+4dBu, which translates as a nominal voltage of 1.227 Vrms, which is called line level
what consumer gear operating levels operate at
-10dBV, meaning a nominal operating voltage of 0.316 Vrms
what are the acceptable levels in analogue
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
describe dBFS
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
what level should your peak values be in a DAW compared to the analogue domain
between -6dBFS and -12dBFS, depending on the transient nature of the material
what are the recommended digital levels for engineers to calibrate analogue VU meters to
- 18dBFS in the UK
- 20dBFS in america
what is the standard monitor calibration level in the film and television industry
0 VU equals 83 dB SPL
what is the K system
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
what are the three tiers of the k system and what are they best used for
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)
what should the 0 in the k systems be equal to
83 bDC SPL with pink noise on each k/rms meter
