I would think the woofer and mid cone should be wired in the same polarity when they are in separate chambers.
Hopefully your crossover will allow the woofers and midrange to be in phase in the acoustical crossover region.
You could wedge a Tupperware box or a pot over the mid to test it out without having to cut any wood.
Even though the cabinet has another port, below the crossover point the capacitors eliminate motor control over the midrange, allowing the mid to be a secondary (passive radiator) port.
If you remove the capacitors, the mid cone would have control down low, and (I bet) the modulation phase inversion would not occur, but the cone would still suffer from IM distortion, both from the extended frequency range and the woofers pushing it.
Have fun!
Art
That all makes sense. I appreciate the explanation(s). The thought behind the 130 mfd was really just to reduce the overlap and increase the power handling.
When I redo the cabinet, I will ask planet10 to help with the box design. He's been very gracious with his time over the years.
You too. You guys are why I love this forum.
Always do my friend, always do.
When I redo the cabinet, I will ask planet10 to help with the box design. He's been very gracious with his time over the years.
You too. You guys are why I love this forum.
Always do my friend, always do.
I thought a series crossover had some magic to do with maintaining driver control at the crossover point, well that's what Rod Elliott said in his analysis. Maybe you need one, Cal?
...runs away...
I've given up on passive xo this low, since your woofers in series are up around 50 ohms say just guessing and equalization is much more trouble than the fixes already proposed. 125 hz is pllxo (?) territory isn't it?
You'll get it to work. This forum might well be renamed widerange though.
edit: this is multiway isn't it
You'll get it to work. This forum might well be renamed widerange though.
edit: this is multiway isn't it
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Actually I've had a couple at this posting...
...oh you meant series XO, I'll get back to you when the margaritas wear off.
Really?
Perhaps but my active gear is at the other house. This is just for fun here at home.
Well ya, that's why I posted it here but in essence it is just a 3 way with the FR carrying the bulk of the load. The woof and tweet are just to fill in what's missing and to use up some stuff that's otherwise gathering dust.
Huh?
This isn't where they will go. It's there to test TV vocals for the time being. See a couple of posts ago.I just hurt myself trying to figure out all the possible phase cancellation modes (suckout) caused by that corner/shelf config. Please tell me you are going to put some panels back there and a large bass trap.
Cheers to all. I am glad to see the involvement in my little project so far. planet10 Dave is the cause. He had some old cabinets and I just sort of ran with it. I think I have learned as much from this one as my others along the way.
Hi,
The capacitor on the FR will add to the natural roll-off of The FR to give
an 18dB/octave rolloff, (this could be quite peaky due to the series
capacitor interacting with the drivers impedance peak and the series
resistances increasing the drivers Qbox), I'd say due to one or both
of these effects the FR ends up out of phase with the bass helpers.
This is one case where cascaded first order series could work well,
though another option is first order series for bass to FR, and then
just paralleling the tweeter x/o with the FR.
A typical mistake is to assume driver phasing is related to the
electrical order of the filters, it can be but generally it isn't as
driver phasing depends on the acoustic order of responses.
rgds, sreten.
The capacitor on the FR will add to the natural roll-off of The FR to give
an 18dB/octave rolloff, (this could be quite peaky due to the series
capacitor interacting with the drivers impedance peak and the series
resistances increasing the drivers Qbox), I'd say due to one or both
of these effects the FR ends up out of phase with the bass helpers.
This is one case where cascaded first order series could work well,
though another option is first order series for bass to FR, and then
just paralleling the tweeter x/o with the FR.
A typical mistake is to assume driver phasing is related to the
electrical order of the filters, it can be but generally it isn't as
driver phasing depends on the acoustic order of responses.
rgds, sreten.
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A capacitor could even increase the output just below resonance due to the nature of the drivers reactance.
Hi,
Yes. See some gory details here for a 100uF capacitor : Zaph|Audio
I've simmed a series equivalent and its much better than parallel.
rgds, sreten.
OK, problem with the drop out and others are now solved. Separate boxes for the mid/high and closed off the holes, and back to being wired in phase.
I can get on with voicing them now. What a relief. Thanks for all the input guys. They are actually a pleasure to listen to now.
I can get on with voicing them now. What a relief. Thanks for all the input guys. They are actually a pleasure to listen to now.
Attachments
It is very gratifying to see that these have served a much higher purpose than being poor firewood.
dave
Chao Tuan,
Cam on ban nhieu lam,
Hi Tuan,
Thanks for your post,
I see you have transposed the location of the XO components on the mid and the tweeter. No I have not tried this. What do you think I might notice? I was under the impression this would not make a difference as it's all part of a series network.
Lam on noi ro hon. Toi rat thich cach lam cua ban.
Please tell me more.
Cam on.
Cheers.
Hi Cal,
I am so happy to know that you can write my language very well. I am living in Ottawa. I am interesting in building speaker crossovers.
From beginning, you said that all drivers have outward motion when battery tested + terminal to +. I think that if you wire the FR and tweeter drivers the way I have, all drivers will move the same direction when playing music. Your speakers may sound smooth and louder. How do you think about this Cal? Is my idea correct in this case?
Thanks,
I am so happy to know that you can write my language very well. I am living in Ottawa. I am interesting in building speaker crossovers.
From beginning, you said that all drivers have outward motion when battery tested + terminal to +. I think that if you wire the FR and tweeter drivers the way I have, all drivers will move the same direction when playing music. Your speakers may sound smooth and louder. How do you think about this Cal? Is my idea correct in this case?
Thanks,
Hi Tuan,
They are all in electrical phase now. I had a problem before that was well explained thanks to those who have a better understanding than me. Now that they are in separate chambers, the problem went away. I still have the XO components on the negative leg but they are in phase.
I must confess, when I saw your name, I asked my Vietnamese wife to help me write in your language. I know very few words myself.
They are all in electrical phase now. I had a problem before that was well explained thanks to those who have a better understanding than me. Now that they are in separate chambers, the problem went away. I still have the XO components on the negative leg but they are in phase.
I must confess, when I saw your name, I asked my Vietnamese wife to help me write in your language. I know very few words myself.
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