Some Kind of WAW with W5-2143

I have been a bit skeptic to the concept of WAW/FAST but I think I finally managed to get something working with my W5-2143. I love the sound of this element running full range but I quickly ran out of x-max with my initial ported design. Great for near field listening or for low volume background music. It lost some of its mid-range magic when I crossed it as high as 320 Hz (in a poor excuse for a WAW). I finally managed to get it into a sealed enclosure with a natural roll-off and a -3 dB around 100 Hz. Assisted by a pair of 8 inch subwoofer elements + plate amps and it actually works surprisingly well.

I have documented the build on my blog if anyone is interested to know more...
... But sealed in a FAST and crossed at 400Hz to 600Hz is ideal. Let the woofer do the mid bass chest punch impact stuff at 120Hz to 300Hz.
I have already tried to cross it at 320 Hz (active 4th order LR). Great to offload it from bass duties since the 2.5 mm x-max is a major constraint. But it is also loosing some of its "full range magic" when used with a HP filter (especially notable at low volume playback). This is why I had to try it sealed with a natural roll-off as low as 100 Hz. It works great as long as you don't push it too hard, like over 100 dB.

I would like to take this concept a bit further, with a high quality subwoofer element (maybe a bit larger than 8 inch, like 10 or 12 inch) and more powerful amps with better controls. I will then consider the use of a HP filter on the W5-2143 in order to increase headroom and SPL. But I will enjoy it "full range" until then. :)
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Go 1st order to avoid losing the magic, make a transient perfect 1st order crossover. It will be seamless transition. With 4th order LR, you have phase wraps and polarity of woofer and full range are inverted. I have done this successfully with the 10F/8424 (most full range can handle it) but woofer needs to be flat and breakup very high to filter it out.

I am crossing at 900Hz and it still has the magic. The woofer here is actually more important than the full range. RS225-8 is unique in this capacity.

I would crossover lower, but that combo does work. I did do a prestudy for a crossover network for a friend with that combo and came to this... This is done on raw measured drivers by the owner and was mainly for having an id what it would become before he started to build the cabinets. So use this only as starting point and at your own risk (i did not build this or tested this).


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Go 1st order to avoid losing the magic ...
Thanks xrk971, great idea why didn't I think about that?!?

I have always wanted to build something with the RS225-8 and bringing it up as high as 900 Hz is one way to go. A 10 inch like a Peerless XLS-P830452 would not go as high but maybe something like an SB Acoustics SB23MFCL45 (a bit more X-max compared to RS225-8)? And maybe cross it a bit lower than 900 Hz? You got me thinking in a new direction xrk971. ;)
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I also have SB23NRXS45-8 and although it has better bass extension, it is not as smooth and wide band. There is more breakup to deal with for a passive XO. But might be fine for DSP. It works very well because all of the dynamics and impact are handled by the bigger 8in and the spatial imaging and sound stage is handled by the full range. But with 6dB crossover slope, you can’t tell which driver is doing the work - it really is a smooth transition.

that TB looks interesting! I think about using one for midrange duties.

i think the TB loose loose its «magic» because either it is not burnt in a bit, either the filter quality is not on par with drivers capabilities, or either it's the combination/integration with the subwoofer that is not as seemless as a fullrange by itself.

you can try different configurations one by one until you notice the lost in «magic». A passive filter or a different woofer or simply play with passive filters or can give you cues.

BTW, if you don't want to spend on costly capacitor, you can try the nichicon BP capacitor, i am using them right now with a rs225+mid/tweet in XRK's build, and they are exceptional value, IMO...very natural balanced easy sound compared to other film caps i have like the dayton's film caps.
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it is difficult to know we refer to as «magic». As i said, you have to try for yourself to see what causes the «downgrade» in sound. Personally, i would run the TB w5 by itself with different filter type to evaluate the cause. Any added part changes the sound.

PS: the capacitor i am using right now are the nichicon DB series. like i said, not the last word in resolution, but it gets out of the way to enjoy the music. That is what it does well, IMO. that said, i haven't try every cap out there, so YMMV.
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