Newbie to car audio...

[SparksLP]

Hello all!
I was hoping someone would be able to give me a little car audio 101 here. I have a Sony Xplode head unit (http://store.sony.com/webapp/wcs/stores ... CDXGT930UI).

If the speakers I put in utilize a higher power output, what happens? Is the sound lower quality or do I lose audio range? I really don't want to have to put in an amplifier, I just want better sound than the factory setup. I was looking at these for the rear deck, any thoughts about speakers for the front?

http://www.newegg.com/Product/Product.a ... netMark_18

My Bonneville has the 2 speaker setup in the door (5 1/4 + a tweeter, I think).
Thanks for any advice!

[sandrock]

Those speakers will work ok, but won't sound their best. RMS wattage of most aftermarket headunits are usually around 22 watts/channel, which works great for factory speakers and lower power aftermarket speakers. Those Polks are 100 watts RMS, meaning you will need an amp capable of 100 watts RMS per channel to get the best possible sound from them.

[SparksLP]

Ok, do you have any suggestions on what type of amp to go with? And is there anywhere in the car that it can go that would be out of the way, I'm trying to keep the car as stock looking as I can. Plus, I hate not being able to use my trunk...

[sandrock]

There are plenty of places to mount an amp, you just gotta know where to look. I'll soon be installing a Kicker KX800.4, and it's going where the jackbox used to reside. You can even use the underside of the rear deck to keep it out of the way. I;ve even replaced the cardboard that covers the rear of the back seat with MDF to mount amps.

[SparksLP]

Cool, post some pictures of the amp when you mount it so I can see how you have it up there. Any suggestions for the front door speakers? I found some Polk 5.25s on Best Buy's website for $89.99. Could I use the stock tweeters with aftermarket speakers? I know they won't sound as good, but I have those already and am trying to go as low cost as possible.

[SparksLP]

Ok, I just ordered these from Best Buy. Polk Audio DXi 6x9 and 5 1/4. I figure I'll give them a listen and then look at amps if I think I need one. Thanks for your help!

http://www.bestbuy.com/site/Polk+Audio+ ... Id=1007091

http://www.bestbuy.com/site/Polk+Audio+ ... Id=1003226

[Bugsi]

I agree you should just hook them up to your head unit and see how they sound. The head unit is rated 17 watts RMS and the front speakers are rated 45 watts RMS. Often these numbers on speakers are inflated. At least the head unit includes a distortion rating. The front speakers have 93 dB sensitivity, so these might be sufficient with your head unit. Best of all, it doesn't really cost you anything extra to try it first without an amp. You can always add an amp later if you need to or want to.

They may sound just fine and you may STILL decide to add an amp later. In general you can expect to drive the speakers louder without them distorting like mad, if you add a decent amp. And of course, with extra amplification you can always add a sub for deep bass. In general, I'm a fan of using a sensibly sized amplifier to improve your sound.

You can absolutely get clean sound out of just a head unit, but it's difficult to get very loud clean sound out of a head unit that runs off [nominally] +12 volts. Traditionally, you can only push a signal + and - 6 volts, for maximum current of around an 1.5 amperes into [nominally] 4 ohm speakers like the ones you bought. That's a maximum of 9 watts you can deliver to a speaker. To get around that, so-called "high power" head units create an inverted copy of the signal, then amplify both the noninverted and inverted versions of the signal in two amplifier chains, and deliver the output from each chain to the terminal pair of each speaker, doubling the theoretical output to around 18 watts. Considering your head unit's rating, that's what its internal amplifier is doing. Solid-state amplifier circuit chips that do all of this in a package around the size of a postage stamp are exceedingly common these days.

To deliver any more power to a speaker [generally] requires an amplifier that includes a high frequency switching power supply. These typically can deliver 50 volts or more, giving you considerably more amplification, which comes with increased current draw from your electrical system.

Give your speakers a listen with your head unit at the volume you like to listen, and see if it's good enough. I use an amp in my Bonneville, but for my wife's Odyssey we just stick with the stock head unit and upgraded speakers, as her listening isn't usually *loud*, since she's usually hauling our kids around. (But I did upgrade the speakers in it.)

[crappiefisher]

You'll like the sound of the Polks, I'm fairly sure that they will sound fine with just the headunit powering them. You will get more low-end and they will sound more dynamic if you amp them though.

[psburtis]

if you have a manual passengers seat you can mount an amp under there. I have a Kenwood KAC-8404 mounted under my seat and it fits great. I also re-wired my car so that I have higher quality wire going to all my speakers.

as for the speakers, you probably should listen to them off the head unit at the volume you usually listen to. it makes no sense getting an amp if you don't crank it up enough to have them distort. I upgraded my head unit before i got any new speakers, so I can't really say anything about aftermarket speakers with a stock head unit.

My aftermarket HU puts out 33W rms per channel, one of the more powerful ones at the time i bought it. Still, after having that with upgraded speakers for a few years, i came to the conclusion that I can't blast my favorite songs without them distorting and sounding crappy. So, I put in the kenwood last summer. It's only 50W RMS per channel, but I can't turn my HU up past about 25/40 without having to roll the windows down to let the sound out.

I also wanted to warn you that it's not how loud you play your speakers that causes the most damage, it's how much distortion you play them at. even nice speakers like the Polk's you bought won't last too long if they are played with a lot of distortion. Also, if you do end up getting an amp, get an amp with RMS ratings a little higher than your speakers RMS ratings. the reason for this is you don't want to have the gain on the amp up all the way, as it will cause some distortion with the amp working as hard as it can. you want to set your amp to about 85-90% of its max power, so it plays clean sound while at the same time playing loud sound to. I would suggest, if you end up getting an amp, getting one that's 50W RMS (they are quite common actually. i believe Crutchfield has one in their Sound Ordinance line that is a very good price and comes with a 3 year warrenty).

Good luck!

[BFF_Larry]

any aftermarket speaker will basically sound better than the stock Bonneville speakers.