Originally Posted by pelked1

Well, I recently realized I can a bone-head at times...the connector that connects the mid/woofers to the amplifier is accessible from the little panel at the front middle area of the door panel...so no need to remove the entire door panel! You can get to what you need through this panel.

I estimate that this will take about 30 minutes per door. What you are doing is installing a 220uF capacitor (a 150uF, 200uF or 270uF would work as well) in series with the mid-woofer. This capacitor creates a high-pass filter that filters out frequencies that are about less than 200 hertz to the mid-woofer, thereby reducing the amount of bass coming from these speakers. This allows the bass control to be raised by about five to seven increments to get the bass from the subs at a higher volume while not overloading the mid/woofs. As I stated before, this little modification does wonders to the low frequency through the lower midrange frequency band. It was enough of an improvement for me to not go out and purchase an entirely new system. Since it will cost less than $5 and only about an hour total, it really is a great modification. You can purchase the caps (2) at Radio Shack for less than $2 apiece.

This is the procedure:

1. Pop off the panel with a screwdriver.
----> Use a small flathead screwdriver and with a little finesse, the panel will pop right out.

2. Reach in and disconnect the rear connector (the one with two wires, not five!).
----> Squeeze in the two tabs on each side, and pull the connector downwards. When it disconnects, there is enough play in the wire to pull it out of the door panel several inches. You will have to pull back the black cloth sleeve that protects the wires inside.

3. Install the capacitor.
----> I have two different procedures for this. Cut one wire and splice in the capacitor using either 1) wire nuts or 2) crimp connectors.
----> The capacitor can be wired in series with either the red or the black wire. It doesn't matter.
----> Capacitor values in this range are usually polarized. This means that one end has to be connected to the more positive voltage side of the circuit. In our case, this is a don't care and it doesn't matter which way the cap is oriented. This is because there is no DC voltage level at the amplifier output (actually there is always a few millivolts of DC, but never enough to worry about).
----> In summary, the capacitor is put into series with either the black wire or the red wire, and it doesn't matter which way the cap is "pointing" in this series connection.

4. Reconnect the plug and pop the panel back into the door. Done! Enjoy your great "new" stereo!

For my tastes, Before the mod, I usually had the bass control set at -7, -8 (or sometimes even -9) to prevent the front speakers from over loading and distorting from too much bass. After the mod, the bass can be put all the way up to around -5 to about +2, depending on the material.

I will state that however easy and safe this procedure is, I am not responsible for any damage incurred by anybody performing this to their Crossfire, either to their person or to their vehicle and/or other property.

Good Luck and have fun!

Originally Posted by ragtop73

I was going through the forum to gather all the info before deciding which caps to buy.
Adoni's post seems to conflict with Pelked1's. Per this, a 67uF Cap would cut MORE bass.
Can someone please comment if my thinking is incorrect.

Thanks,
Jeff

Originally Posted by mstarman

**CLARIFICATION**

Just to clear up some misconception about the capacitor value and its effect on bass filtering. By increasing the capacitor value, you will decrease the CUTOFF frequency, yes. However, this means you are allowing LESS bass to pass through to the speaker. So if you want to have more mid-bass, you should DECREASE the capacitor value. 67uF sounds very reasonable, though 220uF should work fine for most people.

Also, a note on polarization. Non-polarized capacitors would be highly recommended, as other people have commented. For those of you that may have POLARIZED capacitors laying around, you can turn these into NON-polarized capacitors. This is done by putting two capacitors in series, with the 'negative' terminals tied together, leaving the two positive ends to be attached to the spliced speaker wire. Also, keep in mind that when putting capacitors of the same value in series, the capacitance will be cut in half: meaning two polarized 220uF capacitors in series will form a single non-polarized capacitor with a new value of 110uF. Hope this helps.

Michael

Originally Posted by SRT SIX

Mstarman, where are you located?

Originally Posted by mstarman

San Luis Obispo, CA... Not too far from you I suppose. Why do you ask?

Michael

Originally Posted by pelked1

This has been brought up before, but I want to discuss what I have found.

I used to be a big car stereo enthusiast and have built a few pretty nice car audio systems in my time. What I have noticed about the Crossfire (non-base coupe) sound system is that it really isn't that bad... after one small modification is done. The problem IMO is that there is an absolute overabundance of low frequency energy in the 100-200 hertz range with no possibility for the bass control to get rid of… and no fader to control the relative volume of the subs to the rest of the system. I have personally found that I usually had the bass control at about -7 or -8 to reduce the mid-bass sloppiness that it exhibited (IMO, too much mid-bass is the single biggest issue that can make a sound system sound terrible). This "extra" bass energy is coming from the poorly crossed over door bass/mids. In fact, I suspect those bass/mids may be running straight up (or close to it) and contributing way too much energy in that range.

What I did was to install a 200 Hz high pass crossover in the form of a 200 uF capacitor in series with the front speakers. Simple enough if you are a car stereo guy. This little mod does ABSOLUTE wonders to the system. I am absolutely amazed how much quality low frequency energy the subs actually produce. It was there before, but was being muddled by those front speakers and reduced in volume by my having to turn the bass control down so much to control the overzealous mid-bass. The new sound is rich and detailed in all the mid-bass frequencies, and the subs really nicely fill in the lower frequencies at just about the right crossover frequency. The subs do not produce "thumping" volumes, but the quality of the bass is quite good. Subjectively, I estimate that the system is easily producing 40 Hz at relatively good volume. It won't be enough for bass volume freaks, but the quality of the bass is pretty darn good, and I am all about the quality.

This overabundance of mid bass is probably the most common problem that most stock car stereos have. Manufacturers do this purposefully to help compensate for road noise, but it really mucks up the sound, especially in the relatively quiet Crossfire. Once this mod is done, in addition to the huge bass improvement, is that the midrange opens up and sounds so much more natural and smooth.

This mod will not address the issue that some think the head unit is crappy. I would say that it is very average in the reproduction of upper midrange and treble frequencies, and at volumes more than "fairly loud" the sounds gets a bit grainy, but that's about it. Sure it doesn’t have a ton of features, but IMO it looks better than a lot of the aftermarket stereos, at least in our Crossfire. To me, all the spinning circles, flying dots, and multi-color displays are just too much, although I have seen a few units that I like (but big $$$). I prefer the simplicity of the stock unit, and with this mod, it sounds so much better.

I highly recommend this mod to anyone interested in improving the sound quality, but really don't want to spend a lot. It may be just the ticket before resorting to a complete overhaul! It is pretty good bang for the buck mod and isn't too hard to do (depending on your skill set). I can't imagine a stereo shop charging more than about $100 for this mod.