'zactly..........Yankeee slang

Bo,

I agree with everything you said but its getting that to happen in controlled conditions that is the challenge.

Not everyone has experience in these matters, particularly eq and this whole active thing is seen as a quick fix for nirvana by the layman which frankly it ain't. Trying to measue the stuff and interpret sane results it not easy either.

IME for the lower crossover frequencies around 300 hertz, its no boner because of the hump in the upper bass they have with the woofer acting like a bandpass filter in passive mode and less than ideal damping at Fb from the 0.5 ohm dcr Chokes JBL used.

At higher crossover points 800 hertz and above you need to be alot more discriminating and really careful.

The former passive crossover "symptomatic" issues are not as accute but there is a requirement for a lot more precision and this is where the passive voltage drives that have been tailored exactly for a given design are difficult to get right with an active filter. This is where it gets cocked up. ie example 4430/35 people mis understand what is required. Then we have people doing the whole diy deal with 2397 horns atop their big 4 ways

The result is a lot of odd ball screwed up results and noise in threads that then compounds itself later on. A while ago we tried to clean up the Tech forums as a result of this sort of situation where there was a lot of rambling and little if any certification of what was in fact correct.

At some point I think it would be useful to document in a thread titled Biamping XYZ JBLs and list what works with different active crossovers.

The problem as I see it is the 5235 cards are quite scare now for the prescribed JBL crossover settings and we have a experience / education void with more recent members joining and making enquiries..

The other issue is most off the shelf active crossovers are set up for LR 24 db filters and not all are contrinuously variable for frequency selection (exceptions DEQX with required NASA training, the Ashly wihch allows useful variable Q of the crossover point, and the Passlabs which offers numerous discrete settings).

These crossover are the Norm for Pro PA use.

But in use the JBL Pro Series Monitors for example are rarely a classic text book symmetrical filter and getting it right requires a degree of EQ fudge factor if all you have at your disposal is an off the shelf active "pro unit"..

I just think it should be thought out and perhaps slotted into a reference area once the facts are worked out...for a particular case in question

Ian