XO schematics

[kgveteran]

I've noticed that some schematics are all inclusive, meaning the hipass/lowpass/bandpass are on the same plan.

Some are separated.

Can I take a schematic that is all together and divide it up so the hipass is on one board,the bandpass is on one board and the lopass is on another.

Is a XO ever designed to be a unifided filter or all together for another reason.

[ThomasW]

Which one do you want to split?

[cjd]

Is a XO ever designed to be a unifided filter or all together for another reason.

A series crossover should be split with care, if it is split at all. So, Modula MT is such.

A parallel XO can be split with no trouble.

[kgveteran]

Here is the XO design http://home.stx.rr.com/poneal/pdfs/RS150RS28.pdf

I wanted to use separate binding posts for the midwoofer and tweeter.

[cjd]

You can split that one. Some interesting choices made in his design now that I look more closely at it.

C

[kgveteran]

You can split that one. Some interesting choices made in his design now that I look more closely at it.

C

And those choices that are interesting are..............

[cjd]

Tweeter response looks to be shaped at the top end - not something I think sounds as good, probably because it pushes the higher frequency breakup up in dB (though I am not entirely sure that's what I dislike about it). At any rate, it takes a metal tweet I find smooth and turns it into the metal tweeter sound I don't like. But, I seem to be unusually sensitive to this issue (I don't care for the excellent Seas 27TBFC for example)

I haven't looked at the transfer function but it looks steeper than this driver pair needs too.



Should sound good, I'm just being picky. You know, the "Well, I would do it differently" and since I DO my own, I can get away with that. :P

C

[poneal]

Here is the XO design http://home.stx.rr.com/poneal/pdfs/RS150RS28.pdf

I wanted to use separate binding posts for the midwoofer and tweeter.

Yes, you can break it into two. You can buy one of those bi-amp speaker terminals and connect the tweeter to one and the woofer to the other. Those are really nice for measuring because you just take out the little bar that merges the terminals together and then you just connect the speaker wire to the one you want to measure. When your done, put back the metal bar back and your set. This also allows you to put one circuit on the bottom of the box and the other one on the top of the box.

As far as the notch filter on the tweeter goes, it bumps up the response where the RS28 starts to dip. You can try it with or without it IIRC. When I get home I'll model it without to see if the phase is still aligned. It's really more of a personal preference than anything else as my hearing really doesn't go that high. Cheers, Paul

[kgveteran]

IIRC ? ops:

[ThomasW]

One can find virtually anything using google. For example....

http://www.google.com/search?sourceid=navclient&ie=UTF-8&rls=GGLD,GGLD:2004-07,GGLD:en&q=IIRC

[kgveteran]

If I recall correctly I thought it was a technical term ops: .Ya gotta love it.

[cjd]

Paul - I think it would be good to have both versions in your writeup.

C

[poneal]

Good idea cjd

When I model that this evening I will update my writeup. Thanks, Paul

[Marzen]

I haven't looked at the transfer function but it looks steeper than this driver pair needs too.
C

Could you expound on this some? I've been heading down this same path using Jon's elliptical topology to severely attenuate the out of band freqs. Should I be concerned with anything beyond summing flat & phase response?
Ward

[cjd]

You can always, I think, go steeper than needed without much risk (though at this oint I can't say how the sound might change).

It does, however, add cost and complexity and more parts in the signal path. For thid driver combo, there is plenty of overlap where both play happily with the selection of a lower crossover point.


Regardless, this is again a personal choice for the designer and not something "wrong" by any means. More a discussion of philosophy.

I think my problem is I come across as criticizing a lot when I am merely thinking out loud, so to speak.

C

[Marzen]

You can always, I think, go steeper than needed without much risk (though at this oint I can't say how the sound might change).

I'm beginning to recognize the advantage I have with Sound Easy's filter emulator. I've only recently been playing with that feature using an old Boston Accoustic 2 way for testing simulated xo's.

Regardless, this is again a personal choice for the designer and not something "wrong" by any means. More a discussion of philosophy.
I think my problem is I come across as criticizing a lot when I am merely thinking out loud, so to speak.

Understood. I didn't take this or any of your comments personally. I have rough mental notes on most everyones personal tastes & temper their responses in comparison with those; but I'm always curious as to why they lean in a particular direction. As with your dislike of the 27TBFC for example which you've explained. Once I've figured out what I 'really' like and 'really' don't like, then I'll know who has similar tastes as myself.
Thanks -
Ward