Ideal audio reproduction permits gain change and pure delay without degrading quality

Evidence

Another aspect that relaxes the constraints of the definition is that the signal level is allowed to change during storage or transmission, because this can be compensated for using gain control, and often a modifiable reproduction level is very desirable. When delay is permitted and the level at the output is allowed to differ from that at the input, the transfer function for ideal reproduction is Y(jω) = G e−jωT, where X(jω) is the input, Y(jω) is the output signal, and G is a gain factor. — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 496

Categorization

• DEFINE: Gives the relaxed mathematical definition of ideal sound reproduction: any output that is a scaled, time-shifted copy of the input.
• corroborated: 2 independent passages support this claim — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 496