Help with active/passive?

[kenbei 10+ year member]

I have never done active before and have some questions/concerns. I have an audison lrx4.300 which does 65x4 @4 or 210x2 @4. I am considering going active on this amp since I have heard that the xovers on it are very good.

I don't have speakers yet, but I am considering either the focal k2p or the DLS ir 6.3 3way. If I go the Focal, its a 2 way system so to active this one, I would run the tweeters off of the first two channels (A) with a high pass on at about 1200hz, and the woofer on the last two channels (B) with a low pass set at ~ 1200hz also, and have the subsonic filter on.

If I went with the DLS, that is a 3 way setup. so I imagine I would have to use the passive xovers with the set on the midrange and tweet, put them both on the first two channels (A) and set the Highpass at ~1000hz, and run the woofers straight off of the amps last channels (B) low passed at ~1000hz, with the subsonic on.

Am I on the right track? Does that sound right? Say in the Focals case, would I be better just bridging the amp and running 210w to the passive xover? or will going active be better? What do I have to gain really? I know their is greater efficiency going active, but is it noticeable in this config? Do I run the risk of blowing the tweeter running 65w to it (more like 32w since the tweeter is 8ohm)? Am I underpowering the woofer sending only 65w to it? Should I run the extra low or is setting with the multimeter OK?

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[helotaxi 5,000+ posts]

The DLS set either has to e run full active or full passive. The midbass and the tweeter are on the same crossover and the midrange has its own crossover.

Efficiency is a wash between the two. There is very little in the way of loss in a passive crossover. The real benefit to going with an active setup is adjustability. You can tune the crossover freqs and levels to get the exact sound that you're looking for. With a passive, if the freq isn't what you want, you have to rebuild the passive crossover which costs time and money.

 

[dragonrage 10+ year member]

Passive is quite inefficient if you have to L-pad or if you want to do something like a notch filter. You have to bring the rest of the FR down to match your lowest point in such a case. Not that many component sets will come with crossovers that complex, but L-pad is still a concern.

 

[helotaxi 5,000+ posts]

You can make the passive system a lossy and as complex as you want. Most sets sold with passive crossovers though use drivers that are pretty well matched without the need for a hugely complex passive network. As such the difference in efficiency between an active system and one running off the supplied passive network is negligible. If you are going with a prebuilt component set, one of the other benefits of an active saetup becomes moot as well and that is the flexibility to mix an match drovers from different brands and series.