The TC9FD has the wrong TS parameters (too big of Qts) for a 6th order bandpass vented box. It would not work well and be quite large.
The TC9FD has the wrong TS parameters (too big of Qts) for a 6th order bandpass vented box. It would not work well and be quite large.
Ah I see! No worries, I will go back to the TC9FD MLTL design you sketched out in another thread.
The Faitalpro 4FE35 gets mentioned a few times, but I don't see if it is recommended, or the box sixel unless it is the first box size posted. Asthe 4FE35 is the only really affordable driver to play with in the UK I'd love to try this one
Since you're in europe, if you find it, the sica 4e1cs seems to match requirement with qts=0,4 (measured 0,5 on mine) http://www.toutlehautparleur.com/sica-lp-104-25-380-t-8ohm.html and low price.
http://www.toutlehautparleur.com/media/catalog/product/datasheet/sica/Z001800C.pdf
http://www.toutlehautparleur.com/media/catalog/product/datasheet/sica/Z001800C.pdf
The TC9FD has the wrong TS parameters (too big of Qts) for a 6th order bandpass vented box. It would not work well and be quite large.
What's the highest Qts that should work ok in the XKi?
Would something like this be ok at 0.69 ?
Visaton SL87 FE-8 Ohm 3.4" Full Range Speaker 8 Ohm
hi X,
Somewhere you mentioned putting in a hp filter to protect the drivers. Please how did you do this because I cannot find the required inductors (18mH) in current rating above about 300mA which I don't think would last long 🙁. I got the 4FE32's and am about to glue up the boxes. (18mm ply, it's what I had!)
Somewhere you mentioned putting in a hp filter to protect the drivers. Please how did you do this because I cannot find the required inductors (18mH) in current rating above about 300mA which I don't think would last long 🙁. I got the 4FE32's and am about to glue up the boxes. (18mm ply, it's what I had!)
If you are using a digital source like Jriver or Foobar, there are filter settings you can use. To do this passively look at passive crossover finger calculators. For 8ohm and 90Hz high pass you would need to use a non polarized electrolytic cap about 220uF. You can also make your own non polarized capacitor with two back-to-back polarized caps wired in series +-/-+ or -+/+- and use two 470uF caps rated double the supply voltage the amp is powered with if class D as BTL can be double supply voltage. This will give you circa 80Hz to 90Hz 6dB/oct high pass filter for 8ohm driver.
Or use a 2nd or order but that will require two caps and a rather large inductor.
But easiest thing is to use a small class D or class AB amp that doesn't have too much power and you can't blow the driver. A TPA3118 or TDA7297 or TDA8932 with a 12v supply should be fine without a high pass filter.
Or use a 2nd or order but that will require two caps and a rather large inductor.
But easiest thing is to use a small class D or class AB amp that doesn't have too much power and you can't blow the driver. A TPA3118 or TDA7297 or TDA8932 with a 12v supply should be fine without a high pass filter.
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ok, xki with the pa130 plans. roughly 7x7x12" inside size. i followed the plan in the picture with 1/2" ply.
My little lepai 2020 amp in the basement with my $13 microphone. Which I know you guys would not do.
My little lepai 2020 amp in the basement with my $13 microphone. Which I know you guys would not do.

Nice boom/toolbox! That should sound fantastic.
The PA130-8 should be on the tops of anyone's list of full range drivers. If you like budget good sound, try it. 90dB and great vocals with surprising bass punch in the right box.
The PA130-8 should be on the tops of anyone's list of full range drivers. If you like budget good sound, try it. 90dB and great vocals with surprising bass punch in the right box.
I moved them out into the garage on a plywood shelf and that made them a lot more fun. Maybe the basement is too reflective? I broke the pa130's in with some pink noise and music maybe 20 hours. I'm not being real nice to them. They are $15. That also makes them cool.
They can take quite some abuse and won't complain. Glad the sound in the garage is working for you. On a shelf you are probably getting back wall reinforcement for bass.
I might do well to consider picking up a pair of PA130-8s for my kluged 5" K boxes. Somehow in my mind I thought the PA130-8s were 8" (wonder why?). I really need to get back to modifying my boxes but am involved with care giving and just can't seem to get the time.
thanks for the project. I've read most of these huge threads and you've put a lot of time in. I find some wood hacking relaxing but don't want to relearn math because that isn't relaxing.
If a guy put like 4 of these speakers in one cabinet, it seems like it would be a powerhouse and wouldn't require a separate tweeter setup. And it would be 8 ohm which is kid of the downfall of a pa130 x 2 idea. Anyway, thanks again.
If a guy put like 4 of these speakers in one cabinet, it seems like it would be a powerhouse and wouldn't require a separate tweeter setup. And it would be 8 ohm which is kid of the downfall of a pa130 x 2 idea. Anyway, thanks again.
4 would probably be decent - - the most incisive K's I've heard are with a good coax - like 80oz ferrite slug on a 12" - but it takes skill I don't possess or luck for a really nice crossover. A K-tube setup 2-way is a great way to go for smaller K and if done right would be killer. Just one little PA130-8 XKi off the floor seems to be reaching subjectively towards 60-70Hz on a closed miced zarb CD which is much deeper than my old scrap "K5" with the same driver. xrk971 did a great job designing this little K-coupler and TheJessMan did a great job making mine.
wow! - tonality and bass definition is excellent on a zarb trio CD - and that's just one cabinet playing - - if somehow a Beta8cx XKi would sound this good and coherent then would be a good project. (I've got some Beta8cx laying around}
wow! - tonality and bass definition is excellent on a zarb trio CD - and that's just one cabinet playing - - if somehow a Beta8cx XKi would sound this good and coherent then would be a good project. (I've got some Beta8cx laying around}

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hi X,
Somewhere you mentioned putting in a hp filter to protect the drivers. Please how did you do this because I cannot find the required inductors (18mH) in current rating above about 300mA which I don't think would last long 🙁. I got the 4FE32's and am about to glue up the boxes. (18mm ply, it's what I had!)
What 4FE32s did you get? I've seen 3 impedance models, 4, 8, 16 ohms. They have different QTS with the 4 being the lowest at 0.5 QTS.
4 would probably be decent - - the most incisive K's I've heard are with a good coax - like 80oz ferrite slug on a 12" - but it takes skill I don't possess or luck for a really nice crossover. A K-tube setup 2-way is a great way to go for smaller K and if done right would be killer. Just one little PA130-8 XKi off the floor seems to be reaching subjectively towards 60-70Hz on a closed miced zarb CD which is much deeper than my old scrap "K5" with the same driver. xrk971 did a great job designing this little K-coupler and TheJessMan did a great job making mine.
wow! - tonality and bass definition is excellent on a zarb trio CD - and that's just one cabinet playing - - if somehow a Beta8cx XKi would sound this good and coherent then would be a good project. (I've got some Beta8cx laying around}
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Glad it is working out for you. As I recall, the snap on transients is pretty nice with the PA130-8. I made a video of a candle flame being blown out by the upper K aperture air flow from sound of a stand up bass plucks. From the relatively high fs and low xmax spec for this driver you would not think it to be such a good bass performer. But it is.
Here is link to video again for those who missed it. Change asc extension to mov to watch.
http://www.diyaudio.com/forums/atta...tio-karlson-6th-order-bandpass-xki-candle.asc
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