Crossover Help

[xecluded]

Can someone please help me to understand this crossover design in the picture. Low pass is set at 1.2kz and the high is 3khz. What about the frequency range from 1.2kz to 3k.

It's a highly touted design that i saw from the threat here at audiokarma:
http://www.audiokarma.org/forums/sho...d.php?t=150939

Thanks in advance.

[infinia]

Hi

Crossover is at 2.5KHz... the tweeter and woofer sum around the crossover range
tweeter input is Vn002
Woofer is Vn0006

[xecluded]

Does that mean woofer has to play up to 2500. I still dont understand how it can in do that. I need to learn more about these things. thanks for your explanation.

[infinia]

Originally posted by xecluded
Does that mean woofer has to play up to 2500.

Yes... at least to a minimum. Since the filter response shown by the Xover circuit by itself sums almost perfectly, then both drivers should be ideally flat around the Xover region and beyond.

FYI The total response of the speaker is... the bass drivers response in box times the LP filter response summed with the tweeter and wave-guide response times the HP filter response.
This is a math/theory viewpoint. IMO The art here lies in seamlessly matching the final LF+HF off axis responses (i.e. similar directivities) at the crossover point.

[tinitus]

Originally posted by xecluded
Does that mean woofer has to play up to 2500. I still dont understand how it can in do that. I need to learn more about these things. thanks for your explanation.

I dont know which woofer is used, but a few things matters in respect of the "big" series inductor

One is BSC, which means output will be lower below 500hz and is compensated with "attenuation" of higher midfrequencies
Further, your highly effective woofer probably shows a rise in both output and impedance above 1khz, which results in a delay before te xo slope sets in

[infinia]

Originally posted by tinitus

I dont know which woofer is used, but a few things matters in respect of the "big" series inductor

One is BSC, which means output will be lower below 500hz and is compensated with "attenuation" of higher midfrequencies

Not sure of your point here...
Is it concerning that a 95 dB/W woofer is now just an average 89 dB/W just before Xover point? (then requires attenuation of an efficient tweeter/waveguide design by up to 18 dB).

Originally posted by tinitus

Further, your highly effective woofer probably shows a rise in both output and impedance above 1khz, which results in a delay before te xo slope sets in

The rise in output is due to beaming (cone design) which can be useful in matching a wavequides directivity, but a rise in woofer impedance and delay can be absorbed into the Xovers LP filter circuit (see my previous attachment).

[xecluded]

Interesting, most 15" woofers are not designed to go up to 2500 so I thought the cut off low frequency drive for "econowave crossover design" in question would top out at 1200. I am more confuse than ever. Anyway, many thanks for your help

[infinia]

Originally posted by xecluded
Interesting, most 15" woofers are not designed to go up to 2500 so I thought the cut off low frequency drive for "econowave crossover design" in question would top out at 1200. I am more confuse than ever. Anyway, many thanks for your help

Yes, I also think the 2,500 Hz Xover is too high for a 15"... but I don't have any other details either. The crossover seems to be for a generic 2way ...more useful for a 5" to 7" & 1" dome i.e. 2nd order with full BSC.