This I Beleive.

Since we're talking about "stereo", what is the purpose of rear speakers? What value do they add?

(I also add that since this is not an IASCA competitor's forum, my comments are aimed at the general population, not at only those who want to compete in IASCA - in case someone brings that up.)

Historically, rear speakers have allowed low and mid-fi autosound systems to play louder and to play more bass. Rear decks often had larger speakers (6x9, 6" round, or even 5" round) while the front speakers were 3.5, 4" round, 4x6 round, or 5" round, and often had lousy provisions - it was VERY hard to get those speakers to play low notes with any authority no matter what you put in there, due to physical constraints.

When we started putting in subwoofers in the trunk, we often relied on these larger rear speakers to fill in the midbass hole. We'd play them and maybe cut them off at 75 or 50, and we'd have a good flat frequency response.

Then in the early 90's, we realized that 300 Hz was not the threshold of directionality that we had all been told in RTTI, and that shoving that midbass as far forward as possible would be sonically superior to leaving the snare drums and bass guitar in the back seat. (Remember the cars with subs in the floor that started competing around this period).

Also, in the mid-to-late 90's, amplifier pricing started to erode - amps became pretty good deals. So if you wanted to play it loud, you didn't neccesarily need more speakers - if you got higher power-handling speakers, you could get a bigger amp. Instead of 25W x 4, you could run 100w x 2 for a similar output level (close enough in dB).

Fast forward to 2006.

Most newer cars have good front speaker provisions, in both size and mounting method (good midbass potential).

Amps are cheap.

We don't need the volume, we don't need the midbass, and if we want a good stereo image, we don't need the muddling.

As far as reverb goes, we'll get some anyway, don't need more.

If I'm advising anyone on how to get the best sounding audio system possible, what should I recommend - the best front components they can afford, no rears, and a sub - and just enough amp channels to run that? Or shall I take that exact budget and split it up, forcing another pair of amp channels in, perhaps, and getting far lower quality front components?

But most of us have grown up with Dad's car having speakers behind our heads. We're used to rear speakers. That's our reference in a car. We don't have a reason, really - we're just used to it.

Meanwhile, since almost no one has as a reference a good two-channel audio home stereo system any more, we don't have any example of how good 2 speakers can sound (usually, our references have become iPod headphones and crappy PC speakers). (Note to reader - if you haven't heard a really good 2-speaker home stereo system, go to a high-end audiophile dealer and listen to Audio Research, Krell, Thiel, Dynaudio, Magnepan, Mark Levinson (NOT in a Lexus), B&W, or Anthem, to name a few.)

Remember, Quadraphonic failed miserably as a technology, and 5.1 musical recordings are not what we're talking about. "Surround Sound" is mainly for movies, so far, and faking surround sound because it feels good and is pleasureable is fine - but that's all it is, doing what you prefer instead of doing what's accurate.

It's more work to sell a customer on rear speakers actually detracting from sound quality, and sometimes succeeding, than it is to typically sell them rear speakers because they think they want rear speakers, and never present them with a real alternative.

I continue to recommend getting the best front comps you can afford, at the exclusion of any budget on rear comps or rear amp channels. If you want SQ, that's a better path to get it than more speakers, that are more mediocre...

...if you go to a high end audiophile store and say, "Look, I'm on a budget, what would you sell me?" and they sell you NAD and Parasound instead of Krell and Wilson, do they tell you to stack a second set of speakers in the back of the room paralleled with the first?

Getting less-than-insanely-expensive gear doesn't change how stereo works.