power

I can see it now: a whole line of amps at all these different output points! Not necessary nor sensible. You need to double the power to achieve a 3dB increase in volume. 

noromance, hi there. I've read the 'stereo review' magazine from 1970 till there retirement. Julian hirsh wrote that to hear a 3db increase in volume you would have to 'triple' your power.

Many auto amps are made for competition.... In the competition world, they have power classes.  Those classes are normally based on how much total power you have in your vehicle based on a 4 ohm power ratings on your amplifier.  However,  many of these amplifiers are rated at how much power output that they are capable of at 1 ohm or even 1/2 ohm with all channels driven... A few of the excellent competition amps will double their output down to 1/4 ohm load..  
So,  100 watt per channel amp @  4 ohms gives you a 3200 watt amp @ 1/4 ohms …. again, "all channels driven"

It's a "first watt" concept for my tastes. Having owned a lot of powerful amps I've joined the cult of Single Ended esoterica. Efficient speakers (99db) and a little gem of a SEP amp (Firebottle HO...it's a HO) from Dennis Had performs brilliantly,  far better than any mega watt amp I've owned. I do use high power amps (between powered subs, speakers, and passive speakers using high powered amps you get well into thousand of watts even for small-ish rooms) in live sound work as I like the headroom they provide.

"a high current power amplifier  will take you to the next level. Think Amps ..... not watts."

This notion of "high-current" amplifier has made amplifier manufacturers to publish bogus and completely meaningless numbers just to fool prospective - and ignorant, buyers to put their money down on sub-par electronics. Anyone with even the most elementary knowledge of laws of electricity knows that the current delivered by an amplifier is a function of the load (ohms) "seen" by that amplifier. And furthermore, that load varies across the frequency (Hz) spectrum produced by the speaker.
So a high current power amplifier, will not take you to the next level  unless you look at other actually measurable and more meaningful specs.
Sorry about the digression.