I installed the 330uF 65v caps this afternoon, and the improvement is amazing. They didn't quite pass my "Dark Side Of The Moon" test, but I'm still pleased. I also bought a pair of 220 uF caps, but my guess is that they would probably make the door speakers sound too thin and pump too much through the subs. As others have said, I think that something around 270-275uF would be just about perfect. I have had difficulty finding non-polarized caps with that rating, but I'll keep looking.

My installation took about 5 minutes per side. I used the Hot Line Quick Splice connectors, which should make it simple to experiment with different caps.

 

Sounds like a good a good fix. Being able to change around and experiment is great. I used Molex connectors on mine.

Dave
dtinker

 

I did this mod also last weeked, 330 uf caps.
It really does make a difference. Thanks all for the tips and the different cap results.

 

As an experiment, I swapped the 330uF caps for 250's yesterday. I'm putting the 330's back in today.

 

I was going to try this change from 330uf caps to 280uf just to see what it sounded like, but I think I'm going to pass. I like the 330uf sound preety well.

Dave
dtinker

 

I installed 250uf 100v caps and the radio sounded better than any car radio I have heard. Since many on the forum prefer the 330uf caps, I decided to try a pair of 330uf 65v caps this weekend. Now the radio sounds more like the original without the crackling noise in the front speakers. But I prefer the 250uf 100v caps. The sound is clearer and more realistic. Am I the only one who prefers the 250uf 100v caps?

 

I thought about trying the 250uf, but was pretty pleased with the 330uf sound compared with the factory set up. May go back and try it later. I put mine in using molex connectors, so I just need to wire up a connector and plug it in and listen. I have several projects in the works now, so this will have to wait awhile.

 

As I mentioned in my earlier post, I started with the 330 uF caps and switched to the 250's. I switched to the 250's because I felt that I still wasn't getting good clean bass pumping through the subs with the 330's, even if I turned the bass up to 7.

My initial response to the 250 uF caps was negative for some reason, but now I have decided that I like them. I can set the tone controls at flat, or put the treble at -1, and it sounds good to me. I have no reason to go back to the 330's.

 

I might try some 280Uf and see how that sounds. Will let you know when I have some time to get it done.

 

Hi,

i've read this thread and have to say that from an electronic view it's no good idea to only use a capactor in the signal chain. This can harm your amp, because of impedance peaks. It would be much better to use a standard circuit for freqency response leveling. This contains a capacitor, a resistor and a coil.

I've found a tool on the internet where you can simulate the freqeuncy response leveling. It also shows how to wire and what will be the right values for the electronic components (approximate values).

From my experience i would recommend a leveling of -3 to -6dB at approx. 150 hertz.
Personally i prefer the -6dB version. But that's a matter of taste.

Here is the link to the tool: Strassacker: Lautsprecher - Boxen - Selbstbau
The front mid woofers have an impedance of 4 ohm (RE = 3.4 ohm)

Regards
Markus

 

There is an 'A' and 'B' connector on the amp, 'A' has pins 1-12 ( input connector ) and 'B' has pins 1-18 ( output connector ). My only question is : do you put the capacitor in series on the (+) or (-) to the left & right door speakers ?

( pins 8(+) and 18(-) are the left door and pins 7(+) and 17(-) are the right door speaker )
and yes, the amplifier is in the passenger side floor well under a metal guard, easily accessable.

 

I just put mine in the doors behind the access cover.

 

Where in "Deepest, Darkest Alabama"? I thought that was Auburn!

 

I think that Crossfire owners have been performing this simple modification for more than five years, and I am not aware of it causing any problems.

 

I've been using it on mine for a few months, it may cause a problem if you ran it wide open all the time. I have just experienced a much better sound.

 

Are you indicating this circuit will prevent low frequencies from getting to our door speakers?? If so, please explain.

 

It will level the freqency response of the door woofers like the cap solution. It's added to the front channel like the caps. So the circuit does the same than a single cap. But it it will prevent distortion at higer levels, because it compensates impedance peaks.

Take a closer look at the graphics i've attached. There you'll see how much the volume will be levelled at which hertz. You can also use the tool (link) to calculate your own frequency leveling circuit. So you can decide which low frequency will be dampened and how much it will be dampened.

You could do that also to the 4 channels of the subs. But it would be easier to use a simple coil per sub channel to cut off the subs at -6dB a liitle lower. But don't expect too much. The subs are only 6.5" in diameter and have no defined enclosure (they are free air). The amp only producdes 6 x 22 Watt at 4 ohm. So there are limits by physics.

 

Impedance peaks? What are you getting at?

Since when is a speaker a perfect resistance at all frequencies? And your parallel-resonant circuit is reactive as well, it will provide a near resistive load at the resonant frequency, sure, but it will still be capacitive reactive at lower frequencies and inductive reactive at higher frequencies - so what is the concern here?

Blocking caps have been used in the output of single-ended audio amplifiers for decades, since the invention of the transistor, in fact.
What the original poster proposes is nothing new, nor does it violate any "rules" - he simply did some homework for us and published the results.

I am sure you mean well, but as has been pointed out, this mod is over four years old and I have yet to see a thread where someone has destroyed their amp by putting a capacitor in a speaker lead.

 

That is because it hasn't.

 

I put in 220's a couple of months ago and see a little difference. Been thinking of upping the caps. I soulnds like some of you guys are getting better results from going bigger. Maybe later after the TAIL GTG.