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Step 11Preparing The Insides: Part 1: Crossover Unit and Drivers
We are almost done! the next thing to do is mount everything in place and wire it all up.
First we need to mount the crossover unit. I chose to mount it on the bottom of the box. All you have to do is drill a few holes into the bottom of the box and screw it down. I recommend placing some rubber between the crossover unit and the bottom of the box to prevent rattling. If you have a blown bicycle inner tube, those work perfectly, else rubber can be found in many places.
Next mount the speaker drivers. Get some machine screws and nuts that fit the mounting holes in the woofer and tweeter. Drill corresponding holes along the little shelf we routed out in the particle board and then bolt down the drivers! To enhance the look of your speaker, spray paint the screw heads a different color!
The wiring is VERY simple to do. Two wires for the positive and negative leads enter from the terminals and connect to the crossover unit. Two wires (positive and negative) leave the crossover unit and connect to the woofer. And lastly two wires leave the crossover unit and connect to the tweeter. See the wiring diagram for clarification. You will need a soldering iron and solder for this.
Some new stuff (added august 4th): Zobel Network!
Since the woofer is quite large, its impedance rises due to self inductance. The crossover does not take into account this higher resistance. This in turn causes the woofer to sound 'loud' at frequencies close to the crossover frequency. If your woofer is large like this, consider installing a Zobel network across the terminals of your woofer to improve sound quality. The Zobel network will help to restore the impedance to a lower value allowing the crossover to preform correctly. Here is more on Zobel networks. This network consists of a resistor and capacitor placed in series between the terminals of the woofer. For my speakers a 100V non polar electrolytic capacitor and a 10 ohm 10 watt resistor should do the trick (partsexpress has them for pretty cheap). I haven't actually added this in yet but am planning to in the future.
First we need to mount the crossover unit. I chose to mount it on the bottom of the box. All you have to do is drill a few holes into the bottom of the box and screw it down. I recommend placing some rubber between the crossover unit and the bottom of the box to prevent rattling. If you have a blown bicycle inner tube, those work perfectly, else rubber can be found in many places.
Next mount the speaker drivers. Get some machine screws and nuts that fit the mounting holes in the woofer and tweeter. Drill corresponding holes along the little shelf we routed out in the particle board and then bolt down the drivers! To enhance the look of your speaker, spray paint the screw heads a different color!
The wiring is VERY simple to do. Two wires for the positive and negative leads enter from the terminals and connect to the crossover unit. Two wires (positive and negative) leave the crossover unit and connect to the woofer. And lastly two wires leave the crossover unit and connect to the tweeter. See the wiring diagram for clarification. You will need a soldering iron and solder for this.
Some new stuff (added august 4th): Zobel Network!
Since the woofer is quite large, its impedance rises due to self inductance. The crossover does not take into account this higher resistance. This in turn causes the woofer to sound 'loud' at frequencies close to the crossover frequency. If your woofer is large like this, consider installing a Zobel network across the terminals of your woofer to improve sound quality. The Zobel network will help to restore the impedance to a lower value allowing the crossover to preform correctly. Here is more on Zobel networks. This network consists of a resistor and capacitor placed in series between the terminals of the woofer. For my speakers a 100V non polar electrolytic capacitor and a 10 ohm 10 watt resistor should do the trick (partsexpress has them for pretty cheap). I haven't actually added this in yet but am planning to in the future.
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Maybe i'l try to build an active variable x-over..
thanks =)
Did you mean 100uf,,i think microfarad is the unit of measurement for capacitance?
(sorry for my bad english, im just a student)
Deliberately running speakers out of phase is used to stop standing waves in audio installations (high and low points in the room from speakers interfering with each other).
Hope that helps?