Simple Volvo Tweeter Modification

[Maestrours]

In this thread, it's also not entirely clear which values were used for 4 Ohm and which for 8 Ohm speakers. It reads like the value was around 4uF for both, which would say that one speaker type would be passing much lower frequencies than the other. The listener may like that though, and that could mean that using an 8uF for a 4 Ohm speaker may sound better to some people than using a 4uF for that one.

Here's a little plot of the cutoff frequencies vs capacitance for both the 4 Ohm and 8 Ohm speakers. You can see they are not the same.
Note that when using C=4uf, for the 4 Ohm speaker the cutoff is about 20000 Hertz while for the 8 Ohm it's around 10000 Hertz. Using 2uf for the 8 Ohm speaker brings it up to 20000 Hertz, but for the 4 Ohm speaker that would bring it up to 40000 Hertz.

Note these values are for a comparative analysis only. A speaker is actually more complex than a resistor.

Hey,

Thanbk you for this very informative thread;
In my 00 V70, both rear and front tweeters are 8ohms. Front have 3.3uF capacitors, and rears have 4.7uf.
Added this day 4 Dynaudio speakers in place of doors speakers, sound is just at another level!

[MrAl]

Hi,

You're welcome, I did not start this thread though I just contributed.

One of the reasons they 'might' have used different values is because they may have researched the 'chamber' created by the sides, roof, floor, seats, etc., and decided that a little better base response in the back speakers worked better.
What the listeners actually hear is based on the capacitor value, the raw speaker response, and the enclosure, or the 'cabinet' as it's called in IR cabinet modeling, which BTW is very advanced these days. You can even download IR Cab files that mimic some of the well-known older speaker cabinets, if you have a fully advanced electronic audio system.