car audio upgrade, keep jbl headunit?

[calreef18]

I'm looking to upgrade the sound system in my solara, so far I have the stock jbl's with kenwood amp powering 12" audiobahn sub. When I turn my music up I notice that the front speakers get harsh, and also the background noise is pretty noticeable. What would be the best way to get rid of this background noise? Also, if I went with a new set of speakers and tweeters in the front, would that be enough to get rid of the harshness at the higher volumes? Any help/suggestions would be appreciated, I'm definitely a newbie when it comes to doing audio. Not looking to spend too much, maybe $200-400.

[PXLpainter]

Exactly the direction I'd like to go and have been looking lately. I personally love Polk Audio (American made - high quality) and found out that Circuit City actually carries some of their automotive line. They have components and other variations with cross-overs, etc. I plan on going with comonents in both front and rear as well as tossing a sub enclosure in the trunk (I don't want to tear apart my rear seat to frame one in the back).

I've noticed that the speakers sound kinda raunchy and clip the highs if cranked. Also - like most JBL and Bose products, there's almost NO mid-range for warmth, and the bass response if weak.

I can't wait to upgrade my speakers. Good luck to you in what you end up doing though...

[calreef18]

Thx man, I've read back through a lot of posts and it looks like I'm gonna go for a head unit first and then the speakers afterwards.

[JAYDEE23]

the cheapest, best bang for your buck and improvement in volume and sound quality is to simply install a higher powered aftermarket head unit.

the front jbl components are actually impressive for a set of stock drivers if they are fed just 20 watts or so..able to go considerably louder and sound much better doing it.. also the output to your amp will be a better signal than whatever method you are using now..cleaner bass signal for your sub...another audible pro..

your sound quality will increase rather dramatically too (in relation to other sole upgrades such as speakers only etc...)

I had excellent results with an alpine unit with the V-drive amplifiers in it (vdrive is one of the more powerful internal amps available)

The jbl comp set is actually 2 ohm per driver but i had no issues whatsoever and if i recall i could have sworn the alpine vdrives were 2ohm stable believe it or not? was in my car for 1+yrs..

[solaraslev67]

i totally agree with jaydee. when i went from stock to an aftermarket headunit i was amazed by the results. i did not buy any kind of components except for the rear 6x9s since they blew. I had two pioneer premier tsw2000spl subs with a jbl bp1200 amp and a dhd 75x2 amp for the jbls and i have to say that i was blown away. oh yea i also had an audiobahn line driver (eq) that made a world of a difference. First thing you should do is get a new headunit, alpine, eclipse, kenwood, or pioneer would be fine. I have not heard the best from sony. Good luck.

[calreef18]

Cool, I'm scoping out a few deals locally and I'm probably gonna go with a pioneer cd/dvd headunit if the deal goes through.

[lilmike2069]

This background noise is called THD... total harmonic distortion. This is the result of the H/U and amplifier. Basically, with no harmonic distortion, if you arn't playing any music and turn it up all the way, you won't hear that "hiss". Everyone knows that this is near impossible to achieve. But lower THD means lower background noise.

[calreef18]

Picking up a pioneer dvh-p5000mp for a pretty good price tonight.

[swindler]

Is there another way to go?

I'm curious, but if the greatest lift in replacing the H/U is to increase the power to the speakers, couldn't you go with an inline amp? Most of them (I've been looking at the JL Audio / series) can accept speaker level inputs, and then drive your speakers with as much clean power as you want. The only degradation you're likely to see doing it that way is if the H/U amp has high THD or a rolloff in frequency response. But since it's not driving a low impedance load, (i.e., not being stressed), it should hold the signal fairly well.

This is a simpler upgrade, but I don't see it mentioned often. What's the drawback of doing it this way?

[calreef18]

Sweet got the new HU in, sounds pretty good, def a difference from stock. I still think I want to upgrade the speakers however, because I'm kinda selective about audio. Oh, and does anybody know of good places to mount screens? All I can think of is headrests and in dash, otherwise can a flipdown monitor be mounted anywhere good? I have a sunroof btw, so it doesn't look like it.

[lilm]

actually ive found that the biggest difference is changing your componets get a nice pair of tweeters and woofers with a really high sensitivity and thouse highs are going to sound sexy. mine are at a rating of 95 or 97(lol i fogot) and they sound really nice and can get very very very loud......mind you i still got the jbl amp

[calreef18]

Cool, thats the next thing I plan to upgrade, I think I want to go with

[cklinh]

Sweet got the new HU in, sounds pretty good, def a difference from stock. I still think I want to upgrade the speakers however, because I'm kinda selective about audio. Oh, and does anybody know of good places to mount screens? All I can think of is headrests and in dash, otherwise can a flipdown monitor be mounted anywhere good? I have a sunroof btw, so it doesn't look like it.

they have visors with built in screens.

[Monkeyman]

The problem you are describing is called "Clipping." Your factory amp does not have enough power to play both bass and highs at the same time, so it pulls (or "clips") power away from the mid and high sound to power the bass. Upgrading to an aftermarket head would be a good first step to alleviate the problem. It is far easier to blow a speaker with too little power than too much power. With too little power your amp cannot control the speakers properly, resulting in clipping, noise, and other forms of distortion. Buy another head unit, then new speakers, then an amp or two (or three!) in that order. Don't forget, car makers are in business to make money, so the cheaper they can make the factory parts (including the stereo) the higher the profit for them. Even the factory stereo which claims to be a JBL is actually a fujitsu ten, and only has the JBL name on it. Start with a new head unit, and upgrade from there.

Hope this helps,
David

[swindler]

The problem you are describing is called "Clipping." Your factory amp does not have enough power to play both bass and highs at the same time, so it pulls (or "clips") power away from the mid and high sound to power the bass.

Actually, the problem being described at the beginning of this thread may just be THD. THD is generally the inability of the amplifier to replicate the waveform accurately. Any deviation of the waveform from it's original shape is considered distortion. When an amp is running close to it's max gain, it may not have the slew rate to keep up with the signal. Slew rate it most important at high frequencies. The gain stage loses it's linearity, and the waveform distorts. The typical signature is that a sinesoidal wave begins to look more like a shark fin.

THD can also be introduced by the speakers themselves, as calreef18 suggests. The ability of a speaker to follow the waveform of a signal and transfer that energy to an accurately reproduced acoustic wavefront can not be done faithfully by all speakers - and certainly not at high volumes. Cheap speakers will have issues for a variety of reasons. The cones, the surrounds, the voice coil, and the magnetic materiel itself all affects the ability of the speaker to be linear through all levels of sound.

Clipping is a condition when the amp is being starved of power, (or artifically being clamped due to the limits of it's output stages) and the range of the amplified signal is restricted. It affects all frequencies, but it certainly affects bass. Clipping will make the mids and high sound harsh, because the waveform itself is being clipped which puts sharp edges on the waveform. These sharp edges generate a lot of spurious frequencies in the mids and highs, and make it sound VERY harsh. A speaker can also 'clip' if it is overdriven beyond it's limits of travel.

In short, THD is typically attributed to highs, and to some extend mids. So yes, loud bass-driving music will tax the amp to the point where the amp is overdriven and distortion is present in the mids and highs. You are right on target there. But the clipping distorts all of the music - even the bass.