I have some questions (to this always greatly helpfull community!):
1. How do I overcome the nasty impedance peak of the Tang Band W3-881SJF Full range unit? I was hoping to use this as a mid driver from 400Hz to 4000Hz in a 3 way design. But I am worried about the huge impedance peak this driver has.
2. A lot of people are writing or talking online about complex crossovers sucking the life out of the sound.. (am I thinking about impedance correction networks and notch filters here?)
I would like to pair a 10" sealed or 8" ported woofer to this driver, and have a tweeter take over on top where the 3" driver starts loosing on dispersion of energy.
but I am very uncertain how to go about this.. Any thoughts are welcome! (By the way, the speaker is to be used in a domestic situation for stereo music listening in a livingroom. My main goal here is to have as wide a range of frequencies come from a very small point, to obtain fantastic stereo imagery.
1. How do I overcome the nasty impedance peak of the Tang Band W3-881SJF Full range unit? I was hoping to use this as a mid driver from 400Hz to 4000Hz in a 3 way design. But I am worried about the huge impedance peak this driver has.
2. A lot of people are writing or talking online about complex crossovers sucking the life out of the sound.. (am I thinking about impedance correction networks and notch filters here?)
I would like to pair a 10" sealed or 8" ported woofer to this driver, and have a tweeter take over on top where the 3" driver starts loosing on dispersion of energy.
but I am very uncertain how to go about this.. Any thoughts are welcome! (By the way, the speaker is to be used in a domestic situation for stereo music listening in a livingroom. My main goal here is to have as wide a range of frequencies come from a very small point, to obtain fantastic stereo imagery.
Attachments
If it was me, I would chose a crossover point several octaves above the impedance peak. 400hz is two octaves above the peak, so if your crossover is third order, you would lose 36 db by that point (18db/octave at 2nd order) - making the impedance peak much less relevant. If you are building a 2nd order crossover, you should probably cross higher - at 800hz or so (12 db/octave at 2nd order). Given you're using a woofer anyway, is there any reason why you can't plan to crossover at a frequency that avoids this resonance/impedance peak?
If that's not an option, I would try modelling this with an enclosure. That impedance peak is likely largely mechanical resonance - you might still be able to achieve a very decent response if you can control/lower the resonance via enclosure design.
I have a pair of these drivers waiting for a project, and I'm curious if you have any luck! I'm particularly curious about how much they beam - presumably very badly, given there is no off-axis data on the spec sheet and the cones are relatively large for high-end. Please post an update, if you've made progress 🙂
If that's not an option, I would try modelling this with an enclosure. That impedance peak is likely largely mechanical resonance - you might still be able to achieve a very decent response if you can control/lower the resonance via enclosure design.
I have a pair of these drivers waiting for a project, and I'm curious if you have any luck! I'm particularly curious about how much they beam - presumably very badly, given there is no off-axis data on the spec sheet and the cones are relatively large for high-end. Please post an update, if you've made progress 🙂
Use a series crossover.
Thread 'Advantages of Series Crossover vs Parallel for Subs & Open Baffle'
https://www.diyaudio.com/community/...over-vs-parallel-for-subs-open-baffle.404680/
Also
https://www.diyaudio.com/community/...llel-for-subs-open-baffle.404680/post-7488518
Thread 'Advantages of Series Crossover vs Parallel for Subs & Open Baffle'
https://www.diyaudio.com/community/...over-vs-parallel-for-subs-open-baffle.404680/
Also
https://www.diyaudio.com/community/...llel-for-subs-open-baffle.404680/post-7488518
Thanks for your replies! As you can see I have not moved on yet on this project and was just reconsidering it. Rather busy here with other things.
The series crossover seems a good idea, series crossovers have also always appealed to me for reasons completely unknown to me. (I did once do a a 2 way column speaker with series x-over and I liked the idea and the sound of these).
This project for me is still on paper, but also exists as drivers taking up space in their boxes. I do want to move ahead.. But I have two sets of bass drivers: the 8" Visaton w200S-8 and the 10" Peerless SLS-P830668. I want to use the first one ported and the second one sealed. Currently I am thinking of making two sets that fit my bookshelves, so I can choose the best sounding. To save time (and make the fit the bookshelves) I want to make both cabinets a similar size. For both about 30L-45L internal for bass driver seems appropriate to me. I just started thinking about this again..
I do not wish to cross very much higher than 300-350Hz, because I want the vocal range coming from one driver (the Tang Band W3-881SJF) as much as possible. I have the SB19ST-C000-4 tweeter in mind, and intend to cross it in the region of 3000Hz. I also intend to use 2nd order filters.
Also it is good to know: I wish to skip any baffle step correction here, as the speakers will be integrated into bookshelves in a very large baffle of mainly books. This has also been of influence on my driver selection..
Any thoughts or criticism are more than welcome here! I am very glad this thread has come alive again and I will surely keep you posted of my findings!
The series crossover seems a good idea, series crossovers have also always appealed to me for reasons completely unknown to me. (I did once do a a 2 way column speaker with series x-over and I liked the idea and the sound of these).
This project for me is still on paper, but also exists as drivers taking up space in their boxes. I do want to move ahead.. But I have two sets of bass drivers: the 8" Visaton w200S-8 and the 10" Peerless SLS-P830668. I want to use the first one ported and the second one sealed. Currently I am thinking of making two sets that fit my bookshelves, so I can choose the best sounding. To save time (and make the fit the bookshelves) I want to make both cabinets a similar size. For both about 30L-45L internal for bass driver seems appropriate to me. I just started thinking about this again..
I do not wish to cross very much higher than 300-350Hz, because I want the vocal range coming from one driver (the Tang Band W3-881SJF) as much as possible. I have the SB19ST-C000-4 tweeter in mind, and intend to cross it in the region of 3000Hz. I also intend to use 2nd order filters.
Also it is good to know: I wish to skip any baffle step correction here, as the speakers will be integrated into bookshelves in a very large baffle of mainly books. This has also been of influence on my driver selection..
Any thoughts or criticism are more than welcome here! I am very glad this thread has come alive again and I will surely keep you posted of my findings!
XO's break phase rotation.
Ever thought of the Tang Band W2-2243S 2" Aluminum/Magnesium for 500hz on up. The end. No tweeter?
Specifically to the question of beaming of Paul808: Yes, the beaming data is not shown in the Tang band data sheet. Yet however I am not too worried about this, as I chose this driver specifically for this reason: beaming has a lot tot do with the size of the cone, and due to the size of this particular cone I would be surprised to see beaming effects below 3000Hz (please look at datasheets/polar diagrams of other 3" drivers). This of coarse also applies if one wants to start filtering higher. The latter also giving less harmonic and intermodulation distortion.
The reason I selected the w3-881SJF was because I saw it as a midrange that would start beaming at significantly higher frequencies, and therefore should pair well with a smaller 3/4" tweeter that also starts beaming higher than the standard 1" tweeter.
You suspect its beaming is quite bad, but i suspect it's beaming is quite good.. Are you planning to use it with a tweeter?
If you are looking for a polar response: compare several polar responses of other (and better) 3" drivers you can find (be they dome or cone). You will find out that they all start beaming higher than 4500Hz. Perhaps the so called full range driver manufacturers are hiding these details, but better than that will simply be impossible with that driver size.. That is why I wanted to pair it with a small tweeter with a large polar response..
The reason I selected the w3-881SJF was because I saw it as a midrange that would start beaming at significantly higher frequencies, and therefore should pair well with a smaller 3/4" tweeter that also starts beaming higher than the standard 1" tweeter.
You suspect its beaming is quite bad, but i suspect it's beaming is quite good.. Are you planning to use it with a tweeter?
If you are looking for a polar response: compare several polar responses of other (and better) 3" drivers you can find (be they dome or cone). You will find out that they all start beaming higher than 4500Hz. Perhaps the so called full range driver manufacturers are hiding these details, but better than that will simply be impossible with that driver size.. That is why I wanted to pair it with a small tweeter with a large polar response..
Making the chamber for the midrange a multichamber aperiodic enclosure will suppress the impedance peak. I would experiment with volumes, but I'd try 1ltr each. Tightly place a small 1" diameter vent between the 2 chambers, and stuff open cell foam in or glue over it. Measure impedance for verification.
Perhaps the impedance peak is sufficiently reduced if you put a resistor, about 20 ohms, in parallel with the driver.