Can you replace a 5.6uf cap with a 6.8uf cap in a cross-over?

[Macbraaiwer]

Hey there, my 5.6uf 100v non-polorized cap in my cross-over blew up, it is used on the tweeter side.... what difference will it make if I replace it with a 6.8uf 100v non-polorized cap...? will it work or will it damage the tweeter???

[Pete Schumacher ®]

Hey there, my 5.6uf 100v non-polorized cap in my cross-over blew up, it is used on the tweeter side.... what difference will it make if I replace it with a 6.8uf 100v non-polorized cap...? will it work or will it damage the tweeter???

May not damage the tweeter, but it will affect the sound at the crossover point.

[fbov]

Hard to say what the effect might be without a circuit diagram.

What's easy, though, is matching the 5.6uf cap's value. Capacitance adds when caps are in parallel. Find a 4uf and parallel a 1.6uf. The only change I'd make is to understand why it blew and guard against a repeat. 200v caps aren't that much more expensive, but you should never blow a 100v cap due to over voltage in anything but a pro application.

Now if your XO consists only of a 5.6uf cap in series with the tweeter, what you suggest will lower the XO point and send more energy into the tweeter, a bad thing to do if components are blowing. Then again, this calculates like it was a supertweeter, so that may not matter.

Have fun,
Frank

[gowa]

Hey there, my 5.6uf 100v non-polorized cap in my cross-over blew up, it is used on the tweeter side.... what difference will it make if I replace it with a 6.8uf 100v non-polorized cap...? will it work or will it damage the tweeter???

Huh!?

[Face]

http://www.parts-express.com/pe/show...number=027-425

[depthsounder]

I've had the Dayton electrolytics blow up on me before (granted it was in a friend's speaker who liked to party). They are kind of dinky compared to the Bennic electrolytics, but even better is the cap that Face posted.

[Æ]

The question is not can you, but should you.
Yes, it will make a difference, but it depends on a lot of factors.
Your best bet would be to use another 5.6uf capacitor. If possible use a film capacitor instead of a non polArized electrolytic.

Hey there, my 5.6uf 100v non-polarized cap in my cross-over blew up, it is used on the tweeter side.... what difference will it make if I replace it with a 6.8uf 100v non-polarized cap...? will it work or will it damage the tweeter???

[Macbraaiwer]

Hard to say what the effect might be without a circuit diagram.

What's easy, though, is matching the 5.6uf cap's value. Capacitance adds when caps are in parallel. Find a 4uf and parallel a 1.6uf. The only change I'd make is to understand why it blew and guard against a repeat. 200v caps aren't that much more expensive, but you should never blow a 100v cap due to over voltage in anything but a pro application.

Now if your XO consists only of a 5.6uf cap in series with the tweeter, what you suggest will lower the XO point and send more energy into the tweeter, a bad thing to do if components are blowing. Then again, this calculates like it was a supertweeter, so that may not matter.

Have fun,
Frank

Hey Frank!
The cap blew because the amp was too strong, friends borrowed the speakers... I cant find a 5,6uf cap in south africa, I can get to 5.5uf by using a 3.3 + 2.2 in parallel... the XO has got a copper ''coil'' and 2 resistors and the 5.6uf cap in a circuit... whats your take on that?

[Æ]

Hey Frank!
The cap blew because the amp was too strong, friends borrowed the speakers... I cant find a 5,6uf cap in south africa, I can get to 5.5uf by using a 3.3 + 2.2 in parallel... the XO has got a copper ''coil'' and 2 resistors and the 5.6uf cap in a circuit... whats your take on that?

5.5uf is close enough to 5.6uf. Very good. Just make sure that if you use electrolytic capacitors, you use non polarized.
Film capacitors are not polarized and last longer.

If the copper coil (inductor) is connected to the woofer, it functions as a simple first order low pass which blocks high frequencies from reaching the woofer. A capacitor connected to a tweeter functions as a simple first order high pass, which blocks the low frequencies from reaching the tweeter.
The resistors are most likely there for tweeter attenuation, but one would need to see the schematic/diagram to know for sure.

[Æ]

Huh!?

What, you didn't know that electrolytics have a wonderful *sic* tendency to blow up? When they blow up inside an enclosure, it sometimes ends up looking like confetti.
The voltage ratings of electrolytics are typically not as good as film capacitors, if their voltage rating is exceeded they may blow up.
Also most electrolytics are "wet" inside and over time they begin to dry up.
Tantalum capacitors are electrolytics too, but they are "dry."

So you have two reason why I prefer not to use electrolytics in crossovers, amongst others.
They dry out and/or blow up.

[depthsounder]

Usually by the time that happens I have already critiqued the design and would have wanted to change something anyways. The capacitor blowing up is like a timer for an excuse to redo the crossover.