I've been getting some good information and I think some misinformation about audio systems, and I'd like to sort out the good from the bad. When I'm done collecting info I think I'll write a "general audio guide" thread to help others who might have the same questions.

So, FACT...or MYTH? v

1. "You should never buy one brand of speakers for your fronts and a different brand for your rears. You should always try to maintain the same brand for all your speakers" (possibly excluding the sub)

2. From Edmunds.com -
"Therefore — and this is a hard and fast rule that always holds true — when upgrading a factory audio system, the first thing to replace is the amplifier. End of discussion. The only time this would not hold true is when you have damaged speakers.

Why? Because a factory system with a stronger amplifier will sound much better than that same system with replacement speakers but the same old gutless amp."

3. Our factory head unit puts out about 10W RMS per channel

4. Speakers rated at x watts RMS power consumption perform better if you feed them close to .75*x watts. Easy example, a speaker rated at 100W RMS needs about 75W to perform at its peak.

I'll post more questions as I think of 'em. I encourage others to do the same. I actually know more about audio and electronics than I've let on...at least in theory. I'm completely 100% newb in actual installation! Just...never tried installing stuff before, and it's kind of daunting to start with a car whose looks I car about. Anyway...look forward to hearing your questions & responses.

 

1. yes (sorta) if you by the same brand and series of speakers, you will have better tonal matching qualities

2. yes and no. i dont recommend running an amp to factory speakers, but it will sound a hell of a lot better than no amp, as long as it is tuned right.

3. unknown for certain, but most aftermarket head units only put out between 15 and 18 watts rms power per channel, so this may be true

4. not sure, i always advise that is better to have more power than less, i am running diamond d9 components in my front doors with approx 300 watts rms power going to each door, and the speakers are rated for about 225 total, 150 to the mid, and 75 to the tweeter

 

(1) No - speaker mounting location may make one type or brand of speaker a better choice. This is dependent on the application. Generally I like to match speakers as close as possible for tone / timbre but it is ultimately the customers choice. A top of the line Eclipse component speaker for example is a totally different speaker as compared to a Eclipse coax, thus they are far from the same speaker and tonal response and cannot be called the same.
(2) If the speaker is impedence matched to the amp and crossover matched to the amp, you have just created a monster. If you change the amp and the amp is too large for the speaker, you will create the very monster that that site is talking about, a damaged speaker.
(3) Your factory head unit is going to vary with output power all over the map. Same with any headunit, factory or not.
(4) Incorrect but highly subjective as well. Occupant "A" may like the system best at a modrate volume level, Occupant "B" may like the same system at a extreme volume level. Who is right? A speaker does not need any certain amount of power, the rms rating is the maximum continous amount of power that it is recommended to take in order not to self destruct due to the thermal and mechanical barriers being broken. Just because your cars speedometer says it can go 240 km/h does not mean that it has to be driven there. It drives just fine at 50 km/h now doesn't it?

 

Well, I was considering #4 in terms of quality rather than volume. A different analogy to ponder is, the RX-8 can be driven at 2k RPMS, but the performance is going to suck compared to 5k. Do you need to give it 5k RPMS to get the quality you were looking for?

I'm not sure I understand your answer to #2, forbidden, unless you are just saying that be wary of giving your stocks too much power.

Finally, regarding #3, is there not some standard signal (say, white noise low-pass filtered above x kHz so that it rolls off the higher frequencies) that they can use to measure RMS power? I am surprised no-one seems to know the stats of our head unit!

Appreciating the input. I love audio stuff, so researching is half the fun for me, although I'm driving myself crazy (and probably the boards too) over it.

 

Could anybody point me to a site that has general info. about different brands' strengths and weakenesses, if one exists? For instance, Rockford Fosgate is known for good bass response. Boston Acoustics are known for their efficiency. What is Infiniti known for? Alpine? Pioneer? etc. I'd love to compare.

It'd be cool if there was a page out there that broke that down for you, so I'd have a better idea of which brand I'd be most likely to be happy with. Obviously, every speaker model is going to be different, so perhaps generalizing is a poor guide, but I'd be curious to see the generalizations anyway. If a site doesn't exist, then your thoughts?

 

I know MrWiggles has posted extensive test results for Bose Systems. Nobody has probably spend much time figuring out the stats on the non Bose head unit because if they are even half way serious about sound quality, they are going to add aftermarket equipment to it anyway.

 

True or False:

"Your stock speakers are always going to provide more bass than a set of aftermarket speakers. This is because aftermarkets usually leave the bass to a subwoofer and concentrate on better mids and highs."

 

False!

 

Good. I thought that salesman was full of it. This is exactly why it's so hard to go out and learn on your own. You have to wade through the truths and the lies the salesman feed you...

 

Just keep checking out different shops until you find someone that wants to work w/ you. Pressure sales sucks, especially in car audio.