Active crossovers


There's an abundance of info and opinions on just about every topic under the sun in audio, down to the smallest minutiae.

I have problem finding opinions on active crossovers and which sound good, or not. Or which offer good bang for the bucks. Or whether tubed crossovers are better than SS.

So what's the skinny on this?

Oh, and I'd like to ad a Stupid Crossover Question of my own:
The XO will match the levels of the low/high amps, but each amp will have a different sensitivity. Would you have to match the amp levels each time you change the volume?

KP
killerpiglet
KP,

Think first about what active crossovers are all about. There are a couple of benifits; 1) crossing over before amplification means the amps (and speaker cables) don't have to see the whole audio spectrum and can put their power into a more limited frequency range hopefully with lower distortion, 2) active crossovers can be provide alternate filtering as compared to the built-in crossovers, but you need to be careful here the speaker designer most likly spent a great deal of time blending the sound from the different drivers to give a smooth transition between frequencies and 3) active crossovers can be used in conjunction with equalizers or as just a two band equalizer its self to provide room correction.

I went to the von S web site and read some about your speakers. It looks like what you suggested about an active crossover to split the signal into a piece for the base module and one for the mid/treble module will work. It won't give you all of the benifits of active crossovers that can drive each set of drivers for each frequency range but you will still get the advantage of making your amps and cables work over a more limited frequency range. The signals will still pass through the internal crossovers but I think that is also good in your case as von Schweikert went to a lot of trouble in the design of their crossover and I would think that your speakers would not sound as good without their internal crossovers.

So with the goal of offloading the amps and speaker cables I think that your idea would work and I think that this goal would also put a limit on the quality of the active crossover that you would require.

For what its worth this is how I see it.

Good Luck,

John
If you decide to use and active crossover (as I did) and can afford it, go for the Krell KBX.
Krell makes the active crossover for such speakers as the $40,000 four way B&W Nautilus, and has made crossovers for other companies as Martin Logan.

Have fun!
Richard
Guys, you are great!

Couldn't find info on the Krell. I need SE, not balanced. What does the Krell provide?
Any other especific xo's to look for?
As per Rives, looked up Marchand, saw the XM9L for $400. How's this model?

The Bryston 10 seems to go for 1200 or so, the Krell for 1500 (used on these).

KP
The Marchand is quite good. Some have indicated it's better sounding than the Bryston, but I have to admit I have never done a direct comparison. I think it's fair to say that $ for $ it's probably the best out there. If your budget allows for more, then it's difficult to tell which unit is best. As to the Krell, they did have some 60 Hz noise problems at one time. Perhaps that has been fixed, but if I'm not mistaken they quit making the KBX some time ago and getting the boards for the various cross-over points might be difficult. You should look into this carefully before going that route for sure.
Pardon my ignorance. I'm not even sure if this is the proper thread for my question, as it's not related to specific active cross-overs. Some speaker maufacurers compensate for time (distance), phase and even impedance via thier cross-over designs. I would guess that using mulitiple amps would negate the impedance issues but how about time and phase?