Here's one for you car audio guys. I have a JVC head unit (KD-HRD20) that is rated 20W RMS x 4CH at 4 ohms. I replaced my speakers with some Pioneer units that are rated for 30W RMS. The HU volume goes from 0-50 for the high amp gain setting on the HU and 0-30 for the low setting. Sound quality is great in the 0-30 range but when driving 65 mph with the windows down volume can be a bit lacking when you want to jam out. The problem is that when I start to turn the volume up past 35 the quality starts degrading and if it's at 50 sounds like absolute crap. I have the bass turned up on the equalizer to get some decent bass (no sub) to balance the tone range. My question is this: if the speakers are rated at 30W RMS and the radio is only 20W RMS shouldn't I be able to turn the volume up without the sound quality taking a dump? Or does that just mean I won't blow the speakers even though they sound like crap? Speakers are model TS-G1643R by the way.

 

First, your head unit is rated at 20w/channel. If you push it up to near max setting, you're going to be maxing the built-in amp and introduce more and more distortion ("THD" or Total Harmonic Distortion) into the signal.

Secondly, your speakers are at the lower quality level of aftermarket units, and they are a two-way design. They have comparatively weak magnets, and the doors they're installed in have a a large volume of air, and that is not contained and controlled. There are holes and opening in the sheet metal all throughout those doors. You get no back pressure to help control/regulate cone movement and distortion, or much acoustic gain to reinforce your bass output. This means that that woofer cone has to work its *** off to produce any appreciable bass. Most of your audio, including midrange and upper midrange is also being reproduced by the woofer cone, not the tweeter. The tweeter is most likely only covering 1600Hz up. So if you try pushing heavy bass in a distorted signal to them, and then couple that with the notoriously crappy acoustics of Cherokee doors... Yeah, they're going to sound like crap. Put the same speakers in a sealed wood box of about 1 cubic foot and they'd sound so much better you'd swear they were different speakers.

That being said, if you'll follow the advice I gave you in response to your PM to me, and get a sub with a amp, install those, then turn the bass down on your head unit so you're not maxing it and the door speakers out, you'll be amazed at how much better everything will sound. Your simply asking too much of the particular head unit and speakers you have. Not your fault, though. The acoustics of the Cherokee don't make it easy on anyone to get decent full sound without a sub.

 

Thanks for the reply. I had a hunch it was something like that (though I didn't know about the radio getting crappy when it's near the max). I'm going to look at the sub setup you gave me a little more seriously (as in look to buy something) when I get a job again and I think that will help a ton. I know my Pioneer speakers are cheap, that was intentional, but they sound better than the OEM units. I have noticed that the bass is the first thing to crap out while the highs remain clearer, going with what you're saying. I'm learning!

 

I use a 5 channel 1400 watt to power my 5 speakers

 

A quick(ish) way to improve that would be to upgrade you speaker wire. Stock speaker can handle almost nothing. The higher you crank it, the higher the resistance is in the wiring also causing distortion. So make it bigger and make it copper. My setup is beyma components in front. Beyma coaxials in rear. Powered by a rockford t400-4. And 2 xtant x410 subs and 2 hifonics zxi 1010 1 amp per sub. My electrical ugrades are custom 220+ amp alternator charging a dual post yellowtop optima. Forget the model but its the biggest one. Also a big 3 upgrade with 1awg pure copper cable. With a 30 farad power acoustic power cap. I was surprized when i tested it and it tested 1301 cca at 12.78 volts!!! Lol i need more speakers and amps now

 

That is true! And the factory speaker wire is 18 ga. Which is why I run new 16 ga. (1 piece) speaker wire for a stereo install. And had no problems with my 5 channel 1400 watt amp. Pushing 5 Rock ford fosgate speakers. 4 tri-axles (full range) and a sub.

 

Meh, I fixed my problem. I don't need a huge system nor any big subs that eat all my valuable cargo space. I picked up an OEM Subaru under seat sub/amp unit and wired it into my adapter for the head unit. Stuck the thing under the passenger seat and it sounds WAY better now. I can turn down the bass on the equalizer and can turn the volume almost all the way up before it starts sounding distorted. Best part is it cost $21 total plus some of my time to build the wiring harness. There's no way in Hell I would run new speaker wire to all the speakers, lol. WAY too much work for someone that's not building a system!

 

If you still think you are not getting enough power to the door speakers/getting too much distortion, you could always add a couple of the in-line amplifiers (tiny little things... mine fit in the door). If you shop around online, you get get a set for under 50 bucks.

 

Didn't know those existed. The system works well now. Macgyver was right on the money. I just was pushing too much to them. With the Subi sub I'm able to run a "normal" equalizer range instead of having the highs turned down and the bass up. Thing cranks pretty well now (for what I need anyway, I realize that's a VERY subjective statement, lol) and I'm happy with it. It's amazing how much better sounding even a little 6" sub can be. I don't know that I can tell the difference but I also picked up the door tweeters from an Infinity system so that helps a little too for the highs I think.

 

Bose uses them right before the speaker. Or mounted on the back of their speaker. I didn't give up any cargo space. I used the factory speaker locations. 2 5.25s in the front doors, 2 6x9s in the rear hatch, 1 10" sub in the rear passenger side pocket, my amp is under the rear seat. You can not even tell it is in there. Unless you see the remote laying on the seat. Or hear it. I even painted the speaker grills to match the surrounding interior carpet. The head unit faceplate (and remote) is usually kept in the armrest center console. When not in use.