How to connect from a +/- 15v audio circuit to single powered amplifier
Yes, a coupling capacitor in-line between the crossover's output &amp; the amplifier's input will "re-center" the signal to the "artificial ground" inside the single-sided amplifier &amp; avoid having problems when the 2-sided input "crosses ground."
The size of capacitor you should use depends on the input impedance of your amplifier. I'd say a cap with &lt;1/2 the input impedance of the amplifier, at the lowest frequency you intend to push through it (i.e. 310hz for mid, and 3.1khz for high) should be sufficient. However, it's a lot harder to "mess up" by using too large a capacitor than by using one that's too small, so when in doubt, use a slightly larger cap.


Here's a link to a "Capacitive Reactance Calculator" ... tell it what frequency &amp; impedance (reactance) you need, and it'll tell you the value of capacitor to get it; then go to your favorite component supplier &amp; buy the next higher value that they have in stock (no need to pay $75 for a 10.2876358uF capacitor if a 11uF is handy for $0.15).

NOTE: DO NOT USE AN ELECTROLYTIC CAPACITOR FOR THIS...make SURE you use a "non-polar" capacitor. Mica, oil-and-paper, film, thin film, or ceramic are all fine...aluminum &amp; tantalum capacitors aren't fine...the polarized/electrolytics can end up depolarizing &amp; cause very unpleasant things to happen when used as coupling capacitors without adding a DC bias to keep them properly polarized at all times.