hi everybody,

i'm new on here and from the uk. i have just bought a crossfire and i am very interested in this speaker mod as i love my music. looking at the non polarized capacitors you are talking about, would this be what i need to get as i can't get the ones you talk about as i'm in the uk.


http://www.maplin.co.uk//Module.aspx?ModuleNo=12777&criteria=non%20polarize d%20capacitor&doy=6m9

 

Should work. Get the 2.2 and the 3.3 try both and see how it sounds. The 3.3 will cross at about 100 hz so you get a bit more bass from the door speakers.

 

cheers, marauderroy.

most people who have done the mod seem to use:

220 uf
100 vac rms
860 ma max

is the 2.2 and 3.3 1's going to be any good?

cheers.

 

2.2/3.3 = 220/330

 

Hi Everybody,
I've been reading this thread for a while now and have to say I'm tickled that everyone is finding out about this. Since I've designed amplifiers and speaker systems for 25 years now from (concept to release), and since they can be a little complicated, I would like to throw out some real information.

I know some of you already know this, but for a few that don't know yet, the capacitors everyone is using are Electrolytic capacitors. Electrolytic capacitors are polarized.

Some of you have raised very good questions, like polarized or not. The fact is, if the amplifier output ever produced polarized voltage it would immediately destroy the speaker, so it doesn't. The first amplifiers made (dubbed class A amplifiers), had dc voltage on their outputs. These amps used electrolytic capacitors on their outputs to block the dc voltage from reaching the speaker. So I wouldn't worry about this issue.

Capacitors have a voltage rating. Well, the voltage in our CFs are limited to 12 volts so I would use something in the 25 volt range. That gives a little buffering and will make the capacitor last longer.
Capacitors also have a current rating, referred to as ripple current. This rating is what is used to make sure the power in the capacitor is not too high and doesn't cook the capacitor. I would use a capacitor with as high a current rating as possible, though in the audio range this isn't significant using modern electrolytic caps.

When an electrolytic capacitor fails it either shorts itself out, or it opens up like a light switch. So if you notice your bass returning, this has probably shorted and is acting like a closed switch. At any rate, it's a safe failure mode. If the cap fails open instead, the speaker will just stop working and still, a safe failure mode.

Putting the cap in the negative wire will, in most cases, be safer if the wire comes loose and contacts the body. But, in the case of our CF amps, neither side is ground. The amp uses a common method called BI-AMPING, which drives one side of the speaker negative while driving the other side positive. Hopefully, the amp is protected from short circuits (probably is, actually).

Have I done the mod? No. I replaced the head unit so that I could add MP3 capability and an MP3 compatible disk changer. I do turn down the bass on the new head unit though, so I'm definitely going to install this mod. Turning down the bass to reduce the distortion in the door speakers also reduces he bass in the subwoofers (it's a high pass thing, same as everyone has been doing with the caps in the door speakers). I too like clean, punchy bass.
I've discovered that punchy bass requires some midrange action. So, by reducing too much bass in the door speakers, one might reduce punchiness (It's a harmonic thing).

Well, this is pretty long winded, but hopefully entertaining for someone.

Best Wishes,
Polywave

 

In the interest of saving time reading the thread, is the anyone out there that purchased their XF with the optional 6 CD changer? I've read about this option in my manual, but I can't find anything on this option anywhere. I Googled it, and nothing.

Thanks.

 

It wasn't offered. No CD changer option.

 

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

 

Is anybody out there familiar with the phatbox? Would you know when they will have a model for the MB, therefore for the Xfi?

 

Jeff, you are correct. The 67uF capacitors would remove more bass than the 220's. There must have been a typo in the capacitance value in the post by Adoni.

Just make sure that the caps you choose are non-polarized, and if the 220's cut too much bass for your taste, go to a larger capacitor.

I am glad that this mod has worked so well for everyone. Thanks for all the kudos everyone!

 

Hi Zeb,

On my radio...the max volume is 40. Is that true with all our radios? Also, with the 220uf caps, I still do not feel the thumping tight base as I did without the caps. The base is definitely cut down from before in the door speakers...but the rear subs do not seem to be putting out to make up for it...comments?

 

I did the same mod...and I feel the same as you do. I did not like missing the thumping base...with the 220uf cap in...but like the open voice mids that were present now. So...since the car is small inside...I took the cap back out of the left driver side speaker...but the cap in on the passenger side. I set the base at 0 to +2...and the treble at 0 to +1...not I still get the thumping tight base...but also get the clearer mids for clearer voice. Seems to work well...you may want to try it.

Ben

 

Hi Pelked1,

I am a little confused...you mentioned to use non-polarized caps...I thought that was disputed and Polarized electrolytics were fine and polarity did not matter. Are you not saying it does matter and effect the sound quality? Please clarify. That may be the reason some people love the fix...and others say its lacking. What's your opinion?

Thanks...Ben

 

Thanks pelked1!!!

Just did this mod, and WOW! What an improvement you just saved me a lot of $$$ on a new stereo.

I used the 220uF non-polarized from Amazon (Parts Express), and the install took 10 min.

Then I rolled off the treble to my taste, -5 works for me. And all of a sudden, wow! There's midrange! And with it comes warmth, imaging, no distortion, and the annoying door rattle is gone! The piano and vocals on Evanescence My Immortal are stunning now, and the sub-harmonics on Bring me to my Life resonate the chest cavity without the door panels rattling and the speakers distorting!

I did roll of the sub a little ( -2), because it has tons of low bass. So I run Bass -2, Treble -5. vol about 30 most of the time and it sounds great. The stock setup had way too much mid-bass and treble, which sounds great in a showroom for 2 min, but leads to listening fatigue quite fast. The system now sounds far more accurate.

Thanks again, you have made my car so much more enjoyable.

 

Just finished installing this mod. Sounds GREAT! Thanks pelked!!

 

After some further tests while driving, and on more music types, I think there may be too much mid bass loss with the 220uF - fine line between too much and too little...

I have ordered 330uF and 400uF caps to test, since the install is so easy!

Listening in the garage with the windows down and engine off is far different from driving down the road, due to significant masking effects of road noise, etc.

 

It really is imperative to use non-polarized capacitors. The really short answer why is that since we are filtering an AC signal from an audio amplifier, the capacitor will see both positive and negative polarities. A polarized capacitor cannot survive a reverse polarity condition for long. It will introduce a non-linearity (which is a distortion) on the reverse polarity side of the audio signal, and continued use will either short or open the capacitor over time, depending on the failure mechanism. If you listen to music at a low volume, this may take weeks to months; if you like your music loud, the time to failure will be less.

Also, it really doesn't matter if you install the capacitor in the red wire or the black wire, and since the cap is non-polarized, the orientation in whichever wire you choose will not matter either. Some have said it might be safer in the black wire, in case the wire accidentally is grounded. Given the nature of virtually all audio amplifier designs, the black wire is not a ground or at ground, so I do not think that it is any safer to install it there. Just make sure that there is no chance that a wire can become exposed and accidentally touch the chassis of the car.

There are some people that don't like the amount of low/mid bass that this mod removes. If that is the case, try a 270uF or 330uF (or even a 400uF if you really want to hear more of the mid bass). In previous posts in this thread, the frequencies that these filter are listed, and the Amazon dot com web page to purchase these capacitors is referenced (partsexpress dot com has an excellent selection also). Remember to make sure that you get a non-polarized capacitor. Most electrolytic caps are polarized, so avoid them. BTW, as I mentioned in a previous post, the capacitors available at Radio Shack are polarized electrolytics, so do not use those. (I changed the picture I included in that previous post to convey that).

In my opinion, the 220uf capacitor high-pass filter makes the system much more accurate. Some have said that the "punch" is now gone, and I do not understand that. Punch, to me, comes from low bass, and with this mod, the deep bass that the little subs in the back produce really can now be heard. What I heard before the mod was really exaggerated mid bass which really overloaded the door mids and muddied up the midrange, which spilled over into vocals. For me, this has mod cleaned up two problems and has made the system much more enjoyable.

 

Bump for procedure.

 

Why??? It's contained in posts #1 and #21 of this thread.

 

Thanks. I missed post 21. Great write up.

Question for you all...

I am not an audiophile and need things simple.

I find that I drive around with base about -2 most of the time and the treble -3 to -5.

I have problems with trebles. Either my ears are bad or they are good.. I'm guessing they are bad.

The trebles simply distort and become borderline painful.

I would primarily like to decrease the trebles, add the midrange and have the option to keep the base for those special tunes.

Which Cap would be recommended with this in mind? 270...