Actually audio amps are not transmission lines so impedance matching is irrelevant, In fact there is a term that is related to audio amplifier output impedance and that is "damping factor".
If an amp has a damping factor of 100 and a rated load impedance of 8 ohms. The actual output impedance of the amp is 8/100 or 0.08 ohms. This actually describes an amp I built from scratch.
An amp is constrained by V or I (current). An amp designed for a 4 ohm load places a higher I constraint and a lower V constraint than an amplifier designed for 8 ohm speakers. P is roughly (I^2)*R If R is taken as Z and a constant, and since the available I is lower then the maximum power to the speaker will be lower.
You learn a lot when you build one from scratch and you fixed them for a while. |