I have a question. I was thinking about running an active setup but here's where the confusion comes into play. Ok...let's say I have a set of Mb Quart QSD 213's. I ditch the passive x-overs. Now...how would I power the tweets? I know I'd run wires from the radio harness to my amp to power the midbass speakers. But how do I go about powering the tweets?? And what about RCA's?
Ok, here's the deal. To run an active setup, you need one amplifier channel per speaker. So, to run a 2-way set actively (i.e. one tweeter and one mid per side), you'd need a total of 4 amplifier channels (since there would be 4 speakers). You also would need either 1) an external active xover (like the Coustic XM6, for example), or 2) a headunit that has adequate built in crossover (like the Pioneer DEH-P860MP, Alpine 9833/9835, Eclipse 8443/8454/8053, etc etc).
If you are running an external active xover, you would then run one set of RCA's into the active xover from the HU's RCA outputs, then run the outputs from the active xover to their respective amplifier RCA inputs (i.e. the highpass outputs would go to the RCA inputs on the amplifier for the channels for the tweeter, and the bandpass output would go to the midbass's input on the amp). You then simply connect each speaker to the appropriate channel (i.e. the tweeters on the channels with the highpassed input signal, the mid's on the channels with the bandpassed input signal) and you're all set to start adjusting the xover points on the active xover and play your system.
If you are using the HU's internal crossover, then you would run the appropriate RCA outputs from the HU directly to the appropriate inputs on the amplifer (again, highpass RCA outputs to the RCA inputs for the tweeter, and bandpassed RCA outputs to the RCA inputs for the mids). Again connect each speaker to the appropriate channel (i.e. the tweeters on the channels with the highpassed input signal, the mid's on the channels with the bandpassed input signal) and you're all set to start adjusting the xover points on the active xover and play your system.
So, as you can see, each speaker is powered directly from the amp, on their own dedicated channel.
However, I would caution you to not try this if you are a novice. It is very easy to set the xover point inappropriately and either 1) actually damage a speaker, or 2) get results that would actually be worse than if you had just used the passives. You need to really understand how a system
should sound, as well as be able to point out the problems areas and what needs to be done to correct those problem areas.
And, for a simple 2-way setup, you can use any 4-channel that has an input for each individual channel (i.e. the amp needs to have 4 inputs)
