An amp output power is one of the most important feature an amp should have, measured in watts per channel, and the amount of power you need are based on the selection of the loudspeakers, the size and the characteristics of your car’s cabin, and also how loud you like to listen.
Match your speakers required power with the amp’s power output. Some speakers needs more or less power, or often mentioned as speaker sensitivity that measured in decibels, a measure of how much sound output is created with a specified amp power amount. A speaker with lower sensitivity of 88 dB-93 dB will need more power than a higher sensitivity of 94 dB-100 dB or more to play at the same level of volume.
The power output and speaker volume doesn’t have a linear connection. Meaning, an amp with 100 WPC wont play twice as loud as an amp with 50 WPC on the same speaker. The loudness difference wont be significant of only 3 dB. More amp power will make the system easier to handle sound peak without straining and can give better sound clarity.
If you compare two different amp, make sure to know how the power is measured. Usually the power will be measured in RMS (root mean square). Some manufacturers inflate specifications by measuring power at a frequency, let say 1 kHz, instead of the range of the entire frequency of 20Hz-20kHz. When you compare amps with different outputs, make sure to measure them in the same way.
