Are those responses you've shown with or without my series xo? That tweeter response looks pretty steep. Did you use the same sim SW for that image as the others which had a black background?
Thank you jgv, a reality check is a good thing.
Speakerdoctor, I used speaker workshop for this one. It is only a matter of compatibility with files that have dissimilar data points but I think the results should be as good as I suggested earlier.
I did use your crossover (including inductor resistances), as I did for the plot below. Here, I've fudged the phase a little to show how it could possibly look. After all though, a speaker with a good power response doesn't always look perfect on axis and I didn't even ask your listening axis.
Speakerdoctor, I used speaker workshop for this one. It is only a matter of compatibility with files that have dissimilar data points but I think the results should be as good as I suggested earlier.
I did use your crossover (including inductor resistances), as I did for the plot below. Here, I've fudged the phase a little to show how it could possibly look. After all though, a speaker with a good power response doesn't always look perfect on axis and I didn't even ask your listening axis.
Attachments
Well Allen, that looks a lot like my response - except for the rising response above 5 kHz. If you look at SS's data sheet for the D2905/97000, that is not how it tests out. The xo should not affect the response above 5 kHz.
I thought you may have overlooked it 
The interaction is limited at high frequencies because the inductor in series with the woofer gives that branch of the circuit a high impedance. As a result, you can look at the circuit with that part removed. Only the 8 ohm resistor will be in series with the tweeter section.
To show the interaction, this first plot shows both with and without the woofer part. The yellow trace is the response of the lower circuit, and the rest is the normal (upper) circuit.
The upshot of this is that the tweeter response above around 1kHz, being in a voltage divider with a pure resistance, will be entirely controlled by the shape of the impedance curve seen across the tweeter terminals.
With the woofer removed, the second image shows on the left in blue, the tweeter impedance in parallel with the inductance. The black trace is when the 5.6 ohm resistor is put in parallel with the tweeter and inductor. On the right, the corresponding responses, ie: the amount of attenuation, conforms to the shape of the impedance curves. Red is the un-crossed tweeter for reference.
The interaction is limited at high frequencies because the inductor in series with the woofer gives that branch of the circuit a high impedance. As a result, you can look at the circuit with that part removed. Only the 8 ohm resistor will be in series with the tweeter section.
To show the interaction, this first plot shows both with and without the woofer part. The yellow trace is the response of the lower circuit, and the rest is the normal (upper) circuit.
The upshot of this is that the tweeter response above around 1kHz, being in a voltage divider with a pure resistance, will be entirely controlled by the shape of the impedance curve seen across the tweeter terminals.
With the woofer removed, the second image shows on the left in blue, the tweeter impedance in parallel with the inductance. The black trace is when the 5.6 ohm resistor is put in parallel with the tweeter and inductor. On the right, the corresponding responses, ie: the amount of attenuation, conforms to the shape of the impedance curves. Red is the un-crossed tweeter for reference.
Attachments
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Absolutely amazing! After 36 pages of bickering and 3 weeks this thread has progressed to the point where someone has managed to post a simulation of a crossover that is basicly the same as that which I did 10 years ago and for which I posted the link to it on page 10. So we are now not only repeating audio history, but the history of this thread itself. 
Here are the images form that link (just to make it easy for you to view):
Schematic:
L0 = 0.2 mh, R1 = 0.1, R3 = 7, L5 = 2.2mH, R6 = .18. R1 and R6 are the DC R of L0 and L5, respectively.
System Frequenct response:
Individual/system driver amplitudes:
Individual/system driver phase:
System Impedance:
Here are the images form that link (just to make it easy for you to view):
Schematic:
An externally hosted image should be here but it was not working when we last tested it.
L0 = 0.2 mh, R1 = 0.1, R3 = 7, L5 = 2.2mH, R6 = .18. R1 and R6 are the DC R of L0 and L5, respectively.
System Frequenct response:
An externally hosted image should be here but it was not working when we last tested it.
Individual/system driver amplitudes:
An externally hosted image should be here but it was not working when we last tested it.
Individual/system driver phase:
An externally hosted image should be here but it was not working when we last tested it.
System Impedance:
An externally hosted image should be here but it was not working when we last tested it.
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Come on John, let them have their fun.
To point out the obvious...this topology with tweeter rolloff coming from a shunt inductor requires a good sized resistor across the woofer to keep the impedance from dropping too low. It is only suitable where a large padding resistor can be used, i.e. a sensitve tweeter.
David
To point out the obvious...this topology with tweeter rolloff coming from a shunt inductor requires a good sized resistor across the woofer to keep the impedance from dropping too low. It is only suitable where a large padding resistor can be used, i.e. a sensitve tweeter.
David
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Thank you allenb for all your hard work. It's my impression from both yours and Johnk's models that series xo's aren't necessarily a bad thing. At least in my case, with a 2-way and high quality drivers used in a design with modest power demands placed on it, it can be done successfully.
At this point though, it seems sreten's and speakerman's voices have become silent. Perhaps because there was more action than just words?
Maybe now it's time this thread died a quiet death.
At this point though, it seems sreten's and speakerman's voices have become silent. Perhaps because there was more action than just words?
Maybe now it's time this thread died a quiet death.
Thanks Dave, I think
John.
If it helps I can see your concerns, but it gets complicated after that. I believe you are a highly qualified and exceedingly good mathematician. I wouldn't presume to challenge you there. However a word on my own behalf, I wrote for myself complete crossover simulation software which I began over 20 years ago. My point is simply this, if you were to claim that you were pioneering circuits before I was discovering them, I didn't know about it at the time.
I did look at your pages earlier, and if I didn't give them their dues, I'm sorry. My interests fluctuate and perhaps with the attitude of myself or the thread at the time I overlooked them. For what it's worth, I'm now playing with the Sonus Faber style high pass filter myself.
I may have a different view to you on the merits and methods of re-hashing. Though better used sparingly, I feel it is a part of the way a site like this works as illogical or disorganised as that may seem. I'm not looking to put you on a pedestal, but where I have been posting here I have felt secure in knowing others more experienced than myself have been watching over the thread.
Allen
John.
If it helps I can see your concerns, but it gets complicated after that. I believe you are a highly qualified and exceedingly good mathematician. I wouldn't presume to challenge you there. However a word on my own behalf, I wrote for myself complete crossover simulation software which I began over 20 years ago. My point is simply this, if you were to claim that you were pioneering circuits before I was discovering them, I didn't know about it at the time.
I did look at your pages earlier, and if I didn't give them their dues, I'm sorry. My interests fluctuate and perhaps with the attitude of myself or the thread at the time I overlooked them. For what it's worth, I'm now playing with the Sonus Faber style high pass filter myself.
I may have a different view to you on the merits and methods of re-hashing. Though better used sparingly, I feel it is a part of the way a site like this works as illogical or disorganised as that may seem. I'm not looking to put you on a pedestal, but where I have been posting here I have felt secure in knowing others more experienced than myself have been watching over the thread.
Allen
You're welcome. As I was saying to John, your dragging me into this has piqued my own interest. Thank you.
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