Coupling capacitors are a way to protect speakers connected to the output of an amp from a DC bias.
They are not very good at protecting against much else, but since they are so simple they are used quite often in simpler amplifier designs.
The most common method is to hook up a 4700 uf 1.5 x Voltage rated capacitor in series with the output to ground, or to Vneg. A variant on this is to connect two identical caps in series between the positive and negative rail, then connecting the output's return feed to the junction between the two caps.
Any capacitive coupling methods are using the caps as high pass crossovers, but with a very low crossover frequency. regardless, the low-frequency response of the output suffers as a result. what is a better method than caps for protecting the output?
