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[Chuck Wiseman]

Newb to forum. Reading it for years. Refurbing antique EAW rig. JF500's x 8 and BH800's x 8... Looking for opinions on 3 way xover points. Trying to get the 15" mids happening and work in the bass bins. I have used this in a 12 box config some. LOUD...Sounds fair. but the 15's are barely breathing. This may be a no can do considering the JF500 design. I have drilled deep in the archives and posted in the lounge first. Maybe some veteran opinons on this side. Sorry so long...Thanks in advance.

[Thomas Lamb]

How are they setup right now? Are the tops biamped or triamped? I never used the box but the white papers are always a good place to start. If biamped it looks like 300 is the starting point for triamped it's 300 and 1.4 they show +-3db at 50 hz the bottoms in blocks of 4 show +-3db 47-300 what exactly is the issue right now? Are you not getting enough bottom? What are your current crossover points?

[Chuck Wiseman]

How are they setup right now? Are the tops biamped or triamped? I never used the box but the white papers are always a good place to start. If biamped it looks like 300 is the starting point for triamped it's 300 and 1.4 they show +-3db at 50 hz the bottoms in blocks of 4 show +-3db 47-300 what exactly is the issue right now? Are you not getting enough bottom? What are your current crossover points?

Thanks for your reply. Forgive me for not being prepared. It has been quite some time since I ran this rig and have never ran it in a quad array. Not much call for it in my area. It is more a personal goal or mental illness to hear it fire. I Biamp the tops and xover the BH800's at around 200, Mids in the tops at 960, the max the DBX223 allows. The hi components in the JF500's do a great job and the BH800 bins seem right on but, the 15" in the tops seem way behind. I have used the Tops alone 2 way and they seem to respond and function properly. Again, it may be the design of the JF500 that will not let the 15" fuction as a mid.

[Thomas Lamb]

Thanks for your reply. Forgive me for not being prepared. It has been quite some time since I ran this rig and have never ran it in a quad array. Not much call for it in my area. It is more a personal goal or mental illness to hear it fire. I Biamp the tops and xover the BH800's at around 200, Mids in the tops at 960, the max the DBX223 allows. The hi components in the JF500's do a great job and the BH800 bins seem right on but, the 15" in the tops seem way behind. I have used the Tops alone 2 way and they seem to respond and function properly. Again, it may be the design of the JF500 that will not let the 15" fuction as a mid.

If its biamped and you are crossing it at 960 that is way to high. EAW is suggesting 300 so you are asking the 15 to cover a range much higher than the box was designed for it to cover. There are many 2 way configurations that use 15s and horns and cross them that high and higher (960hz) but the issue with that on this design is I think the box is dictating that its not designed for that. I would probably start with crossing the BH800s at 100 or a little lower and lowering your current config from 960 down closer to 300 and see where is goes. I think its also important that you have a high pass on the bottom end of your subs but where im not quite sure 30 would be good start higher may be better. I guy like ivan will be able to offer a better suitable highpass for that style box.

[Mac Kerr]

Thanks for your reply. Forgive me for not being prepared. It has been quite some time since I ran this rig and have never ran it in a quad array. Not much call for it in my area. It is more a personal goal or mental illness to hear it fire. I Biamp the tops and xover the BH800's at around 200, Mids in the tops at 960, the max the DBX223 allows. The hi components in the JF500's do a great job and the BH800 bins seem right on but, the 15" in the tops seem way behind. I have used the Tops alone 2 way and they seem to respond and function properly. Again, it may be the design of the JF500 that will not let the 15" fuction as a mid.

As Thomas said, the biamp crossover point for the JF500s is 300Hz. This is the crossover between the 15" and the 10". The 10" is crossed over passively to the compression driver at 1.4kKz. The BH800 is not a sub, it is another low frequency element that covers the same range as the 15 in the JF500, 50Hz-300Hz. It has a recommended range of 50-250, with a HP filter at 40Hz. Even with a crossover between the BH800 and the JF500 of 100, you still need to cross the lows of the JF500 to the mid/hi section at 300. This leaves only the band from 100-300 for the 15 in the JF500. It might not sound as loud as you expect, and with a bandwidth of 50-100 and power handling of only 300W program, the BH800 may not as well. If the drivers as old as the boxes I wouldn't want to drive then too hard.

FWIW, the dbx 223 crossover has x10 buttons on each range knob, giving then the range of 45Hz-9.6kHz for each crossover filter. Since the highest frequency you need is 300Hz you should be fine. If you want to triamp the JF500s and quad amp the whole system you need another dbx223 so you can use 1 for the 300Hz and 1.4kHz crossovers for the JF500, and another for the 40Hz HP and 100Hz crossover between the BH800 and the the dbx that is controlling the JF500s.

Mac

[Chuck Wiseman]

As Thomas said, the biamp crossover point for the JF500s is 300Hz. This is the crossover between the 15" and the 10". The 10" is crossed over passively to the compression driver at 1.4kKz. The BH800 is not a sub, it is another low frequency element that covers the same range as the 15 in the JF500, 50Hz-300Hz. It has a recommended range of 50-250, with a HP filter at 40Hz. Even with a crossover between the BH800 and the JF500 of 100, you still need to cross the lows of the JF500 to the mid/hi section at 300. This leaves only the band from 100-300 for the 15 in the JF500. It might not sound as loud as you expect, and with a bandwidth of 50-100 and power handling of only 300W program, the BH800 may not as well. If the drivers as old as the boxes I wouldn't want to drive then too hard.

FWIW, the dbx 223 crossover has x10 buttons on each range knob, giving then the range of 45Hz-9.6kHz for each crossover filter. Since the highest frequency you need is 300Hz you should be fine. If you want to triamp the JF500s and quad amp the whole system you need another dbx223 so you can use 1 for the 300Hz and 1.4kHz crossovers for the JF500, and another for the 40Hz HP and 100Hz crossover between the BH800 and the the dbx that is controlling the JF500s.

Mac

Thank you guys for the info. I felt the low components of both boxes were too similar. The JF500's work great alone but the BH800's get the horns up when ground stacked. I will tinker on with the 4 way or subs on aux possibly. Thanks again.
Chuck

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