Active crossover options

[monstermoo]

I've been thinking about making my Linn Isobariks aktiv lately, and of course to do this I will need to aquire an active crossover.

The obvious answer is the dedicated isobarik aktiv box from Linn (very hard to get hold of and probably would need servicing), then there's the NAXO 3-6 from Naim, easier to get hold of but then I would also need a dedicated power supply - neither option is cheap (at least not to me) and I have been advised that there is no cheap/quick fix solution.

However, I was wondering if something like this might do the trick...
http://www.dolphinmusic.co.uk/category/pa-&-live-sound/processors-&-fx/crossovers/

I'm not too clued up on this stuff, so by all means if this is a ludicrous idea or the solutions here are simply likely to give very poor results - feel free to let me know:mental:


Thanks

Steve

[twelvebears]

I've been thinking about making my Linn Isobariks aktiv lately, and of course to do this I will need to aquire an active crossover.

The obvious answer is the dedicated isobarik aktiv box from Linn (very hard to get hold of and probably would need servicing), then there's the NAXO 3-6 from Naim, easier to get hold of but then I would also need a dedicated power supply - neither option is cheap (at least not to me) and I have been advised that there is no cheap/quick fix solution.

However, I was wondering if something like this might do the trick...
http://www.dolphinmusic.co.uk/category/pa-&-live-sound/processors-&-fx/crossovers/

I'm not too clued up on this stuff, so by all means if this is a ludicrous idea or the solutions here are simply likely to give very poor results - feel free to let me know:mental:


Thanks

Steve

Hi Steve.

Having played around with active crossovers many years ago, I'd be very interested to give them another go as, in theory, they offer significant advantages once you get around the need for additional channels of amplification.

What I don't know is how well an active crossover designed for pro/PA use would stack up against a simple, well designed passive x-over using well chosen, high quality components.

Designing good active designs is a complex matter and really needs to be aimed specifically at the intended design (i.e. driver, amp and enclosure specifics) to get the best out of it.

By definition, these are designed to be 'Jack of all trade' units rather than something aimed and very critical listening in a home environment.

[twelvebears]

One looking at them more closely, one of the obvious questions is whether any of them allow the roll-off slopes to be adjusted. If the high and low pass filters can be adjusted for roll-off, frequency and time delay, then they would offer a relatively cheap way to experiment with active drive (assuming you have the required channels of amplification). If however, they are fixed at the 'industry standard' of 24db/octave, then they probably won't do well in domestic design, as gentle roll-offs are more often used to integrate drivers smoothly.

[Kris]

There's a US company specialising in high quality active crossovers. Will custom make one to spec as well. http://www.marchandelec.com

Kris.

P.s. See http://sound.westhost.com/biamp-vs-passive.htm for a discussion on Active Vs. Passive Crossovers and http://sound.westhost.com/bi-amp.htm for a discussion about the Benefits of Bi-Amping

[twelvebears]

There's a US company specialising in high quality active crossovers. Will custom make one to spec as well. http://www.marchandelec.com

Kris.

P.s. See http://sound.westhost.com/biamp-vs-passive.htm for a discussion on Active Vs. Passive Crossovers and http://sound.westhost.com/bi-amp.htm for a discussion about the Benefits of Bi-Amping

Worth a look but definately not a cheap option, so a bit of a gamble unless you're 100% sure about things.

The Behringer ULTRADRIVE PRO DCX2496 looks interesting as it appears to offer fully flexible roll-off slopes, level adjustment and time delay, all in the digital domain.

I must admit that I'm quite tempted to have a play myself.....

[smithy]

I bought an Ashly XR2001 from a guy who had been using it to tri amp his isobariks ,he sold it because he got the dedicated Aktiv crossover with Bingo boards and Dirak power supply.

[DSJR]

The Behringer bits may be tweakable by Audiosmile, at least on output chips and possibly power supply.

A Naim crossover is extremely simple for what it is with no driver eq at all and early bolt up ones may be available for not much, although you may need to re-cap it at some point with some decent modern caps to replace the cheapo sh*t they put in originally. Avondale Les can supply a great power supply and Flashback Sales some decent phono to DIN cables..

Briks are very strange things and on many examples up until the "convertible" ones, no two pairs ever sounded quite the same. Active ones appear to have less bass, so be warned and they don't always go very loud either for all the power you shove into them. Just turning up the bass level doesn't work..

Linn's aktiv Isobarik Tunbox crossover was very complex indeed, having some driver eq as I remember and the Bingo increased very low frequency bass to make you feel seasick on a vinyl source (ok, the fruitbox of the late eighties). The sound was more neutral, but like the Kan II, the sound became forced and "strained" although with modern amps this may not be a problem..

Best get some ADM9.1's, you know it makes sense and they go as loud and almost as deep as the Naim 135 powered active 'briks....