bi-amp'd, with passive mid/high ??

[dickinsonc]

changing over to a bi-amp'd system (pro-audio "mains").
There is an existing crossover, which I was planing on eliminating BUT... There are midrange and hi-freq horns (the cabinets were 3 way). I'm assuming I can just run the crossover as a two way (the woofer would not be connected) without any problems......... correct?
or , would this work and be possibly better??
Seems the midrange horn "likes" a 800 - 3500 hz range...
Would it hurt the horn-driver to just feed it the full bi-amp signal (over 1000hz) and then just put a cap in line with the hi-horn?
thanks

 

[wintermute]

I think you are better off keeping the existing crossover for the mid/high and feeding it the signal from the highpass of your active crossover. you will almost certainly upset balance if you change the upper two drives crossover in the way you have suggested

Note that you may also find you need to experiment with the lower (active) crossover as well as matching the transfer function of the original passive crossover probably will not be as simple as dialing in a frequency and slope.

edit: I'm assuming the original crossover is a simple parallel one. If it is a series crossover then all bets are off!

Tony.

 

[dickinsonc]

Thanks Tony....
Have no idea if it is series or parallel... if memory serves, it fed the woofer up to 800hz (or so) then the mid 800 to 4500 and passed the highs on after 4500. So.... I'll just let the woofer tap "hang-loose" and see what happens........

 

[wintermute]

If you can, I think you should remove the woofer filter from the speaker connection altogether. having an unloaded crossover may in fact damage your amp.

if it's a parallel crossover then it should be easy enough (unless it is all on one pcb) to disconnect the woofer part of the crossover from the rest, as each branch of the crossover (bass, mid, and tweeter) should effectively have it's own +ve and -ve connections to the speaker terminals, ie the filters are effectively separate, but connected in parallel.

Tony.

 

[dickinsonc]

Actually I was thinking of just stuffing say a 5 watt 8 ohm resister across it... Theoretically, there shouldn't be any (very little anyway) power coming out of the woofer side as it should be snuffed at the active crossover...

 

[wintermute]

good point! I was thinking about a resistor but was thinking it would have to be a big one, but you are right there should be very little power at those frequencies anyway due to the active crossover.

Tony.