PDA

View Full Version : 2.2uf capacitor for tweets running off HU



butterMilk
07-12-2012, 01:52 AM
I have HAT imagine tweeters that I would like to run off my HU. I have been told that I need a 2.2uf cap in order to do so. Do I just solder it inline to the positive wire running to tweeter, close to the tweeter?

Is this a good one? Auricap 2.2uF 400V Capacitor 027-674 (http://www.parts-express.com/pe/pshowdetl.cfm?PartNumber=027-674)
The better ones only come 2.0uf and 3.0uf

The headunit will be avhp8400bh. It has built in crossovers but not the 5000-6000 that I need.

keep_hope_alive
07-12-2012, 02:12 AM
Correct

butterMilk
07-12-2012, 02:48 AM
Thanks!!

Was going to buy it, until I saw that shipping for 10$ worth of product, was about 25$.

Why So Cereal?
07-12-2012, 11:27 AM
Thanks!!

Was going to buy it, until I saw that shipping for 10$ worth of product, was about 25$.

Did u try partsexpress.com? That's where I got my caps

keep_hope_alive
07-12-2012, 02:26 PM
Did u try partsexpress.com? That's where I got my caps


that is what he linked.

note that 2.2uF at 8ohms is 9000Hz
2.2uF at 4 ohms is 18000Hz.

i think you should verify the impedance of the tweeter, then buy a cap that gives you a 5k-6kHz crossover point

even better would be to buy a 12dB/oct passive crossover. PE sells them for 4 ohm and 8 ohm.

ChevyRidinLow
07-12-2012, 02:31 PM
waiting for someone to say "capacitors dont do ****" haha

maylar
07-12-2012, 03:05 PM
that is what he linked.

note that 2.2uF at 8ohms is 9000Hz
2.2uF at 4 ohms is 18000Hz.

i think you should verify the impedance of the tweeter, then buy a cap that gives you a 5k-6kHz crossover point

even better would be to buy a 12dB/oct passive crossover. PE sells them for 4 ohm and 8 ohm.

2.2 uF is what Hybrid Audio recommends, which would imply that the tweeters are 12 ohms at the 6K crossover point. I might verify that someday soon...

butterMilk
07-12-2012, 06:44 PM
Would I be able to just take a DMM to the wires on the tweeter, to find out the ohm rating?

maylar
07-13-2012, 10:38 AM
Would I be able to just take a DMM to the wires on the tweeter, to find out the ohm rating?

No. The DC resistance won't be the same as the tweeter's impedance at the crossover frequency. Need an AC voltmeter and oscillator for that, which I have. HAT says 2.2 uF is correct, and the link you gave is to good quality ones.

keep_hope_alive
07-15-2012, 02:43 PM
yes, a DMM measuring DCR will give you an idea what the impedance is. DCR is slightly less than nominal impedance. should be sufficient to determine if it's 4 ohm, 6 ohm, or 8 ohm.

given the ability for the imagine woofers to play up quite well, a high crossover point can work - if the speakers are on-axis.