Hey everyone,
I am a little discouraged. I really dont like the highs in my car. The components are very good, so i can only assume its my install. I am running a set of CDT HD62's up front in a set of Jim85IROC kicks. They are being pushed by a JBL BP80.4 bridged down to 2 channels. So the speakers see about 170watts RMS. (Rear fill runs off the deck)

I hate them.

It sounds like garbage. The music doesnt have the definition i think it should & it doesnt really get as loud as I though it would. I talked to the vendor who sold me the speakers & he said that the speakers should be in a .3cu/ft enclosure. He suggested building door pods.

I am sure everyone is going to suggest buying a new amp... But before I go spend $250+ on a new amp, I really want to make sure that is the problem. Any suggestions?

 

well a bunch of things you need to consider are: howsare you adjustments on your amp and headunit set?? is there any deadening material in your kickpanels? also keep in mind that just because an amp had a certain amunt of power doesen't mean that it's clean power. a good quality amp with a small amount of power can produce a cleaner sound then a lower quality amp with higher wattage. look at specs such as you signal noise to ratio, total harmonic distortion, what crossover settings you have. you will notice high quality amps have a lot more adjustments to tailor your sound. I have had great luck with amps such as us amps, memphis, JL audio, and zapco to name a few. they are at a lot higher price but nice clean sound and plenty of adjustments to get it sounding the way you want. HTH

 

I know how to tune the HU & amp for the speakers. Below is a list of specs on the JBL amp. Let me know how they look:

-Frequency Response: 10Hz-320Hz
-THD+Noise:.05%
-Signal to Noise: >100db
-Input Sensitivity: 250mV-4mV

 

"-Frequency Response: 10Hz-320Hz"

Unless that was a misprint,there's your problem.

 

What crossover is being used?

Replace amp (just to test and listen)

What deck r u using, was it working good before?

How does it sound not bridged?

Using good wire / RCA's, etc...??

Raf

 

Yeah that was a typo. Should read: 10Hz-50kHz

Running the crossovers that came with the speakers
HU = Pioneer DPH7600 - Never had a problem with it before
I havent tried unbridging it because it will only put out 80watts or so.
Wire & RCAs are the good stuff.

 

Just bought a Phoenix Gold X200.2 Xenon. I will let you guys know what happens.

 

It's hard to say specifically what it is, but chances are it's a combination of things.

One thing I noticed when I built those kick panels for you was how deeply recessed the tweeter is in the housing. That's a really poor design, and one that is especially troublesome in off-axis situations. Unfortunately, that's 90% of car installs. A great deal of the tweeter is obscured, and is likely having cancellation issues as a result of the partial blockage. Because most tweeters come with a swivel cup and a much more shallow mounting design, my kick panels were designed with that type of adjustable tweeter in mind. Your tweeters are probably not a great match for that particular design. However, I have found that the entire foot well area is pretty reflective, and tweeter positioning tends not to be too critical in our cars. Yes, aiming them differently will effect how loud the highs are, but hasn't seemed to impact their clarity. In my IROC I'm using a set of non-adjustable tweeters, and the highs are still very clean and detailed.

As CDT has said, they recommend a larger enclosure. Their drivers are a high-q woofer like most companies use. This does create a bit of a problem when installing them in kick panels, and it's one of the known trade-offs when using kicks. You sacrafice bass and midrange flatness for the superior imaging and soundstage. Some speakers are more adaptable than others when it comes to kick panels, but usually the effects can be EQ'd out. Typically you'll get a midbass bump in output, followed by a sharp dropoff. The dropoff can't be helped, but you can EQ out that midbass bump and get a much smoother sounding midbass. This will be noticable especially on male vocals.

Lastly, the car itself can introduce a harshness in the 2-3k range. I think this is a result of panel vibration. It's not an audible "buzz" or anything like that, but comes across as harshness. A layer of dynamat on the metal kick panel area, the floor beneath your feet, and even on the outer door panel will help this. It also doesn't hurt to damp the plastic dash pieces with dynamat.

Unfortunately, I doubt that an amp will help you. It sounds like you had plenty of power in the first place, and the sound quality won't likely change much from one to the next. What I would suggest is that you thnk about an EQ that has enough adjustability for you to trim the midbass properly, as well as to restore a little bit of output on the top octave. A decent parametric EQ should help quite a bit. A lot of new head units have this function, and with some time spent tweaking I think you'll be able to make great strides. An even better alternative would be to get an outboard 1/3 octave or parametric EQ.

Unfortunately, I think your best solution is to use speakers that are better suited for a kick panel installation, and especially something with a tweeter in a more conventional mounting cup.

 

Thanks for all of the info Jim. That must have taken a while to type. I had a couple ideas that I thought may help...

-I feel like some of my problem is that it sounds like the music is coming from the floor. CDT offers a UpStage system which is basically an extra set of tweeters that you mount up high on the dash or A-Pillars.

-I was wondering if it was possible to create a "box" inside of the void in the chasis behind the kicks. There is plenty of space in there... I would just have to find a way to seal if off.

-The dynamat idea is something that crossed my mind as well, I am almost sure I will be doing that.

I really would like to keep these speakers. I paid a good amount for them & I know I wont get back even half of what I paid for them. Also, I doubt that it would be easy to modify your kicks for a different set of speakers.

 

I haven't tried CDT's upstage kit, but a lot of people seem to like it. I'm skeptical because I've found that it's usually most important to stage your midrange and not your highs. With my kick installs I've always had a very high soundstage and never had that "at my feet" sound. One thing I would suggest which is a real easy thing to do is to reverse the polarity on either the driver or passenger speaker. I've found that the imaging with speakers in that type of location always improves when I run the speakers out of phase with each other. In many applications this will kill your bass, but with kick panel speakers you don't have any anyway.

There's not enough room behind the speakers to make it worth sealing things off. In fact, there's so little that I intentionally avoid any kind of gaskets because the "leaky" nature of my setup helps avoid a lot of that boxy sound. the only way to get enough airspace to really seal it would be to cut a lot of the metal behind the kicks and 'glass in a cavity, but you're talking about a major project there. Another issue is reflection. With the kicks that close to the back of the speaker, you get a reflection that can cause the cone to resonate, which causes distortion. On most of the sets I built I packed some polyfill into the cavity between the speaker and the kick panel. You may want to try removing that and replacing it with something more effective, like some acoustic mat (like whispermat) or the 1/2" thick carpet underlayment that Home Depot sells. These will help prevent some reflection.

 

Well, I got the PG Xenon X200.2. Hooked it up last night & it did help. Not as much as I was hoping, but there is definitly more clarity in the highs...

That was for an hour.

Then the amp fried itself. Just my luck. These amps are some of the most reliable ones out there & I find one that is defective. Oh well, I will send it back & get another.

 

you haven't accidently turned on any processing in the head unit have you? (not that I have ever done that though lol)

 

Update:

I dynamatted the area around the kicks & put alot of insulation in and behind the kicks. What a difference. I actually have bass coming from the front of my car now. (Other than the engine)

Thanks for the help everyone, I am much happier with my setup now.