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Instructions
Determine the nominal impedance for the speaker that your amplifier needs. It is expressed in ohms or the uppercase Greek letter Omega (Ω) per channel, which is indicated at the back of your amplifier above or below the speaker terminals. The impedance also is in the technical specifications section of an amplifier's user's manual. Matching the impedance with your amplifier ensures maximum power transfer between the two devices.
Check your amplifier or receiver's per channel power rating. It is expressed as Continuous Watts or Continuous RMS (Root Mean Square). The information is in the device's user's manual, usually in the technical specifications section. Power is another specification to help you choose the right DIY speaker kit. Get one that is closest to the continuous power per channel specification of your amplifier or receiver.
Install the raw drivers from outside the speaker enclosure holes meant for tweeter and woofer. This placement eliminates unwanted diffraction coloration caused by a hole's edge if you install the drivers from the inside. Use all the screws meant for each driver to ensure equal pressure on the driver frame.
Screw down the crossover network at the internal side of the back board near the enclosure terminals or in the slot designed for the purpose as per your kit's instructions. Some DIY speaker kits have the crossover network already soldered as an integral part of the enclosure terminals. That means there's no need to wire the two.
Connect the speaker terminals to the back of the speaker enclosure using all the screws provided for that purpose.
Cut cable wires in lengths that will connect the installed raw speaker drivers with the crossover network. Do the same when connecting the crossover network with the enclosure terminals. The wires can be only 1 foot long, but you can approximate the distance better by laying out the cable between solder points. Provide enough allowance for the drivers to be taken out if they ever need replacement.
Solder all wire leads to the raw speaker drivers and their other ends to the appropriate points on the crossover dividing network. Wire the tweeter to the "Output HF" and the woofer to the "Output LF" sections so labeled on the crossover network. Observe the correct polarities when connecting -- positive to positive, negative to negative.
Solder the wires connecting the crossover network and the enclosure terminal if the crossover network is not integral to the enclosure terminal. Some DIY speaker kits allow for bi-wring, which means you have a total of four terminals instead of just two -- a separate set of low frequency (LF) positive and negative terminals and another set for high frequency (HF) terminals. Connect the terminal lugs corresponding to the "Input LF and HF" sections of the crossover network. Most terminals are color-coded, with red for positive and black for negative.
Measure the overall impedance at the enclosure terminals after you're done with the assembly. Use a multimeter tester for this purpose with its positive (red) and negative (black) probe leads connected to the positive and negative speaker terminals, respectively. Set it to read in ohms at the lowest range that allows you to read from 1 to 20 ohms or 50 ohms, depending on the multimeter scaling. You should read about 5 to 6 Ohms for an 8-ohm speaker. This is lower than the specified nominal impedance of 8 ohms because the multimeter reads only the static direct current (DC) circuit resistance without the alternating current (musical signals) components in the impedance.