Active crossovers

I'm using a Marchand XM9-3 Deluxe to tri-amp one system. I'm pretty pleased with it over all. The biggest drawback to this design is the lack of variable crossover points. You basically have to install very inexpensive "resistor packs" to adjust frequency. While it is not really a big deal, it's nowhere near as convenient as having an adjustable pot on the faceplate. It is probably a LOT more precise though. Other than that, i've only used professional grade crossovers and they did not sound as clean or focused. Nor did they offer the added versatility of the "blend" or "Q" adjustment that the Marchand has.

Mike Bates ( aka "Magnetar" on AA ) has used a Marchand that he built as a kit along with a Behringer model. He said that the Behringer has some nice features and works better on the low frequency range whereas the Marchand is cleaner up top. He also said that the Behringer has some features that he's found to be quite useful that are not available on the Marchand. He's a very experienced "tinkerer" who's judgment i trust and respect.

There was a Pioneer crossover that was made that seems to be relatively sought after. I noticed that while i was looking for one, there were other "wanted" ads posted for it on both A-gon and Audioweb. Can't remember the model right now, but it offered you the choice of four different slopes ( 6, 12, 18, 24 db's per octave ) along with some other nice features.

My brother is currently using one of my older professional grade crossovers that i used to use when doing pro sound reinforcement at concerts. It offers variable slopes ( adjustable from 1.5 to 12 db's per octave ) and variable crossover points for each band. This one comes in very handy as it makes it easy to find optimum crossover points when building speakers from scratch. Once he's got the cash, he's going to go into a Marchand. I hope it's soon, as i've got a large line array ( 54 drivers per cabinet ) that i need to start "fine tuning" in terms of crossover points. Sean
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BTW just saw on ebay somebody paid $3500 for a set of vintage Marantz x-overs!!Seems a bit steep but....

Active crossovers are a tricky topic, imho.

I'd recommend using an active xover for subwoofers and a passive xover for the rest in general.The advantage here is that you can use a clean, high power amp for the sub bass and select an amp that is optimal for the main speakers (as compared to driving everything from one amp)

It is very easy to muck up some very high quality sound with a not so wonderful HP filter made from not so wonderful opamps and caps (not to mention the power supply).

On the other hand it is possible to implement surprisingly clean and good xovers with both tube and solid state parts. Regardless, it is a good practice to compare the speaker in question with and without an active xover in line.

Much depends upon you, your ears, and your system as to wheather or not an electronic xover will be an improvement or a deficit. Which means there is NO single answer.

In general, the commercial "pro sound" products do not have truly audiophile "sonic signatures" so I would be cautious about them in general.

The advantage of an electronic xover for a DIYer is certainly one of flexibility and ease of adjustment, so it has merit on that point. On the other hand you do need an extra amp or so to use it, so perhaps the money is better spent in other directions?

Ymmv with electronic crossovers in general.

_-_-bear

As has been touched on above, the "purist" solution for the VR4 is to passively biamp. Putting an active xover in the signal path is going to introduce unnecessary processing. The top and bottom modules of that speaker already have high pass and low pass filters (respectively) that allow a full-range amp to drive each. The only "compromise" that will be needed is some sort of signal splitter at the output of your preamp, unless you are luck enough to have 2 outputs on the preamp. I would strongly advise against trying to bypass or modify the internal filters of the VR4, which have already been optimized for module integration.

Interesting, Ral, Albert sent me an email staing as much.
The trick then, is to find amps with similar sensitivity.
So now, to look for an SS amp to match 99 magnums?

KP