Audio Engineering

22 Chapter 1 time, the output waveform must be the sum of all the sounds. An ideal microphone connected by ideal amplifi cation ...

Audio Principles 23 The phase angle is obtained by multiplying the angular velocity ω by the time t. Note that the angular veloc ...

24 Chapter 1 The velocity of a moving component is often more important in audio than the displacement. The vertical component o ...

Audio Principles 25 1.11 Root Mean Square Measurements ......................................................................... ...

26 Chapter 1 voltage, the same power would be dissipated by a DC voltage whose value was equal to the square root of the mean of ...

Audio Principles 27 turned out to be about 600 Ω. In transmission lines the best power delivery occurs when the source and the l ...

28 Chapter 1                Figure 1.22 : (a) The logarithm of a number is the power to which the base (in t ...

Audio Principles 29 The Bel was found to be an excessively large unit for practical purposes and so it was divided into 10 decib ...

30 Chapter 1 is attempting to drive what amounts to a short circuit and can only develop very small voltages. Furthermore, shunt ...

Audio Principles 31 Line up is often done using a 1-kHz sine wave generated at an agreed level such as 0 dB(u). If a receiving d ...

32 Chapter 1 References ........................................................................................................ ...

Measurement Don Davis and Eugene Patronis 2.1 Concepts Underlying the Decibel and its Use in Sound Systems ..................... ...

34 Chapter 2 10 10 40 10 602 1 2 log log . P P   W W dB (2.3) 10 20 20 10 602 12 2 log 2 log . E E   V V dB (2.4) 2.1.2 The ...

Measurement 35 The following defi nition is from the IEEE Standard Dictionary of Electrical and Electronics Terms, Second Editio ...

36 Chapter 2 For example, if a 2:1 change is equivalent to 3.01 dB, then log multiplier Base   log. log ()301 2 10 (2.6) o r 1 ...

Measurement 37 If a 2:1 change is equivalent to 6.02 dB, then log multiplier Base   log. log ()602 2 20 o r 20 log 2  6.02. F ...

38 Chapter 2 For a power of  12 dBm: 0.001 10 0.00006309 W. 1012   The voltage across 600 Ω is EWR   0 00006309 600 ...

Measurement 39 2.3 Expressing Power as an Audio Level ...................................................................... The ...

40 Chapter 2 2.4 Conventional Practice ......................................................................................... ...

Measurement 41 and 1/1000  0.001. Note that any E 2 and R 2 that result in a power of 0.001 W may be used. We can then write: L ...