|LoudspeakerBuilder.ca - (Loudspeaker Parts Replacement)|
So you decided to fix your old damaged speakers instead of buying or building new loudspeakers; these are some of the things that you should know about and take into consideration before buying loudspeaker replacement parts.
Follow the replace in pairs rule so that both of your loudspeakers will continue to sound identical. When replacing any defective drivers (midrange, tweeters, or woofer) in one loudspeaker do yourself a
favour and do the same in the other loudspeaker. If you replace just the blown woofer on one loudspeaker without replacing the other loudspeakers woofer, the sound quality of both loudspeakers will suffer. This is because two woofers of different make, model or age will not sound exactly the same even if the thiele-small parameters do match. The only exception to this rule is if you can get the exact replacement parts and your loudspeakers are relatively new.
Replacements should be of the same quality and type as the original and the replacements parts should be of the same composition of the replaced speaker so that you don't "color" or change the sound of the loudspeaker .So replace a silk tweeter with a silk tweeter and not a titanium tweeter; if the original woofer has a paper cone replace it with a paper coned woofer and not with a polypropylene coned woofer.
Another important thing to remember is to get a replacement with the same resistance. If your original driver was 8 ohms and you replace it with one that is rated at 4 ohms your Loudspeaker is going to have some problems. Changing the resistance's of the original drivers will "mess up" the crossover network's properties and your Loudspeaker won't work as it was designed. This is because the crossover networks crossover points will be shifted away from where the designer wanted them to be. This could be very detrimental to the sound quality of the loudspeaker.
Also pick a replacement speaker which closely matches the original speakers Thiele-Small Parameters; unfortunately these values are often not given or available. Some of the more important thiele-small parameters that you will need to know are:
- SPL (sound pressure level) - It is a representation of the efficiency and loudness that you can expect from a speaker relative to the input power. So it should seem logical to choose a replacement which has the same SPL as the original. This will keep all the components (tweeter, midrange and woofer) at their proper loudness in relation to one another.
- Frequency response - Your replacements speakers must have the same frequency range (or better) than the originals so that they can handle the frequencies sent to them by the crossover network. If you replacements don't match or exceed the original components frequency response the sound quality of your loudspeakers will suffer. Often some gain can be had by upgrading to better quality components such as replacing a woofer with one which is capable of lower frequencies or replacing a low quality tweeter with a high quality one which is capable of higher frequencies than the original.
- Match the speaker to the enclosure- All tweeters that I have ever seen are rear sealed so they are not effected by the volume (size) of the loudspeaker enclosure. All woofers and some midrange drivers are not rear sealed so the sound they produce is heavily influenced by the air volume (size) of the enclosure they are installed in. For the best results you must match your drivers to the enclosure they are being installed in.