Car Stereos: max vs, rms, watts rms, car stereos

Question
QUESTION: what does max, rms, and peak mean in relation to speaker power?

ANSWER: Hi Shaun,

Max and peak are to be completely ignored.  They're unrealistic numbers given by marketing droids.

Speakers are rated in how much wattage they can reasonably handle.  RMS is the rating of how much power they can reasonably sustain for a long period of time.  Use that as your barometer for how to match them with amplifiers and how much power to actually send to them.

Justin

---------- FOLLOW-UP ----------

QUESTION: im sorry, i misworded that question,although the answer is probably still the same.  what does max, rms, and peak mean in relation to head unit power?


Answer
Hi Shaun,

It sure does.  Max and peak are usually completely unattainable outputs in the first place.  Most car stereos are fused at 15A.  15A * 12V = 180w.  180 watts of electricity are available to the deck.  Period.

Many decks claim to be 4x50.  Somewhere, theyre getting an extra 20 watts on top of the fact that it would assume there's no electricty at all being used for sound processing, spinning the CD, lighting up, etc, and they're assuming 100% efficiency.

It's nonsense.  Most headunits reasonably put out about 10-20 watts RMS out of 4 channels which is perfectly acceptable for most uses, and if you want more power, you amplify, and use the headunit only for really hig frequencies which require lower wattage to create higher dB.

Justin