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Bi-amp I have an Adcom 5802 that has bi-amp posts on the back. Do these posts have a crossover for highs and mids or what exactly do they do?

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After examining a picture of a 5802 ( I have been servicing adcom for over 20 years ), these are not bi amp posts, but bi wire posts.

Bi-amp means that 2 amps are being used, one for highs, one for lows. This means that you have no crossovers in the speakers, instead, you have an electronic crossover between the amps and the pre-amp. The highs and lows are separated in the electronic crossover. One amp handles the lows, one handles the highs.

Bi-wire means that you have the crossovers still inside the speakers. The amp handles the full range of music ( highs-mids-lows ). Different kinds of speaker wire produce different results. If you have bi-Wire terminals on your speaker, they come with shorting wires, that tie the tweeter + to the woofer + on the back of the speaker, and the tweeter - to the woofer - . When the shorting wires are removed completely, you have now electrically separated the tweeter and woofer from each other, while maintinaing the crossovers ( inside the speaker ) for each.When this is done, you can now bi-wire the speakers and amp, and use different kinds of wire for the lower frequencies and the upper frequencies, depending on your ears ( everyone hears a little differently, thats why there are so may makers of components, and wire ).

Why do we have crossovers?.....the tweeter voice coils ( the things that make the sound ) are made of hair thin wire. This wire cannot handle much power and if you were to put bass in to a tweeter, you would burn the tweeter out almost instantly. A tweeter is a very light, fast moving device which can react very quickly to high frequency sounds ( symbols, triangles, guitar strings....). Woofers are more rugged. They have voice coils made of heavier wire and are designed for larger movements that Bass demands. Subsequently, woofers aren't very good for high frequencies because they are slower devices.

So what do we do ?.....Keep the lows away from the tweter and the highs away from the woofer.....thats the job of the crossover.

In the event that your speaker has the crossover OUTSIDE the speaker box, you should check ( as always ) with the manufacturer of the speaker to see how it can be changed to suit your needs. Remember to always read and follow your owners manual. Good luck....Rob

Posted on Mar 03, 2008

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