Passive or active crossovers

Hello,

I am purchasing a set of Focal Utopia 165w's and I am wondering what would give better quality of sound: The passive crossovers that come with them or use the active one on the Amp?. I amp I will have will be the JL 300/4. There are a few questions I would like to have answered, as this will be my first system (a JL 13W7 and JL1000/1 will serve as bass in the system).

1) If I go with the amp crossovers, would the 75x4 power rating be too much for the Focal Tweeters to handle? (The amp would power the 2 tweeters and 2 midbasses in the system)

2) Would passive crossovers introduce a lot of distortion and burn out if I bridge the amp (150x2) if I choose the passive route?

3) An Amp question: Since I am going for sound quality but have had no real car audio experience would another amp be better? I heard a lot of talk about the XTANT x604.

Any healp would be great!

ChrisLeclaire

well let me touch on the quality of sound issue first.   IN crossover design (analog filtering) the order of the filter is very important, is it 6dB, 12dB, 18dB etc.???   In the passive world, since it is post amplifier, in order to get a good frequency response a 18dB crossover network is usually the best bet, for a good passband response and well attenuated signal in the stopband.  However, since the signal is amplified it is often more difficult to get good clean components at a reasonable price that will perform the task at hand, so if you took a spectrum analizer on your output (post crossover network) you may notice a decent amount of passband ripple (or distortion).  Now, in order to get a good response with an active crossover, your task is much simplier, since you are operating at low levels, you can use operational amplifiers (opamps) and caps and inductors to get the job done, and have a very clean output, and achieve a much better response with a much cleaner input into the amplifier (since your not adding any distortion from amplification and you don't have to try to filter out noise etc).  Whenever you amplify a signal you introduce some level of noise/distortion to your output signal that gets convolved with the original factory signal, then you have to filter that and then crossover the output (now granted good amps usually don't experience a lot of these problems).  So, i personally like active crossovers, because I can get a great response post amplifier for minimal cost, but I typically build my own, so that puts me in a different scenero than you, so, heres what I would do.

If I am running a component set then I would use the passive xover network that came with.  If I am running a sub from an amp, the built in crossover network is just fine to act as your Lowpass filter and you are set.  If I am running just mid range, I may or maynot use the amp built in stuff, based on the specification I would have to check what my speakers are rated at and what the amps crossovers are rated.  

As far as blowing stuff up, burning it out etc, just check to see what the crossover networks you have claim they can handle, and typically the components in them are rated about 15% higher in power than what they claim, but its more to the point of what your speakers can handle, but that is why there are Gain adjustments on the amp, so you can prevent the blowing of your speakers.  

Craig