Back from our summer hols - we in the southern hemisphere have Xmas and New Year during the hottest months which is kind of nice, though I guess snow would be too - and I decided to try something a bit different from the Karlsonator, reverting to a woofer-assisted wideband design in a PVC cylinder bend but with homemade waveguides. I guess I just wasn't getting enough oomph from the W5 Tangband.
So this design just uses an inductor on the 10-inch RS270P-4 Dayton woofer and no crossover for the Mark Audio 7MS. The waveguides I constructed from lamp shades; just shave off their bottoms really with one of those multitool vibrating saws that nurses use to cut plasters off broken limbs.
Suffice to say the bass is back, though that's largely due to the fact that I can biamp these things, the Burson Bang for the 7MS and a 125wpc DIY audio design for the 10-inchers.
I like the improved staging with these too, there's real depth now and better imaging than with the Karlsonators. I'm not sure I have the right sized inductor which is set for around 250Hz but I figured start there and head back down. Might try 150Hz next; guess it is best to let the 7 MS do as much of the voice as possible. Any suggestions re optimal x-over point would be welcomed.
They're not quite as aesthetically pleasing as the Ks but they are certainly different. The Mrs hasn't seen them yet....
So this design just uses an inductor on the 10-inch RS270P-4 Dayton woofer and no crossover for the Mark Audio 7MS. The waveguides I constructed from lamp shades; just shave off their bottoms really with one of those multitool vibrating saws that nurses use to cut plasters off broken limbs.
Suffice to say the bass is back, though that's largely due to the fact that I can biamp these things, the Burson Bang for the 7MS and a 125wpc DIY audio design for the 10-inchers.
I like the improved staging with these too, there's real depth now and better imaging than with the Karlsonators. I'm not sure I have the right sized inductor which is set for around 250Hz but I figured start there and head back down. Might try 150Hz next; guess it is best to let the 7 MS do as much of the voice as possible. Any suggestions re optimal x-over point would be welcomed.
They're not quite as aesthetically pleasing as the Ks but they are certainly different. The Mrs hasn't seen them yet....
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they look very pleasing to my eyes. The waveguide should work very well - what lampshade in particular did you employ?
here's a rough idea for a PRV 10FR300 XKi. I don't have hornresp so don't know what length the duct should be if 12 inches wide by say 1" tall (?)
10FR300 has 2mm xmax by overhang and "4mm" xmax including 0.25X its 8mm gap height. The other inexpensive FR would be Visaton's BG20. I'm not sure what it would require space wise.
here's a rough idea for a PRV 10FR300 XKi. I don't have hornresp so don't know what length the duct should be if 12 inches wide by say 1" tall (?)
10FR300 has 2mm xmax by overhang and "4mm" xmax including 0.25X its 8mm gap height. The other inexpensive FR would be Visaton's BG20. I'm not sure what it would require space wise.
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Thanks guys.
The waveguides are just cheapy $4 lampshades 25cm in diameter.
They're surprisingly okay to work with; the plastic doesn't tear and they're quite flexible, easy to cut and sand. I used to make holes for the screws to pass through but now just cut out small squares with the inner side open because you don't see the holes anyway.
Today Im trying different inductors, to bring the upper level for the woofer no higher than 115Hz. I think a bit much voice is getting through to the woofers at 250Hz cutoff and they don't do voice that well seemingly. Hopefully the MA 7MS will delve down that low. They are in their own little enclosures within the cabinet, which is otherwise sealed.
Im quite enjoying these and they're very easy to make; will create some nicer circles for the baffle at some point as those were just ones that were hanging around.
The waveguides are just cheapy $4 lampshades 25cm in diameter.
They're surprisingly okay to work with; the plastic doesn't tear and they're quite flexible, easy to cut and sand. I used to make holes for the screws to pass through but now just cut out small squares with the inner side open because you don't see the holes anyway.
Today Im trying different inductors, to bring the upper level for the woofer no higher than 115Hz. I think a bit much voice is getting through to the woofers at 250Hz cutoff and they don't do voice that well seemingly. Hopefully the MA 7MS will delve down that low. They are in their own little enclosures within the cabinet, which is otherwise sealed.
Im quite enjoying these and they're very easy to make; will create some nicer circles for the baffle at some point as those were just ones that were hanging around.
PVC elbow prices could be bad in the US. Home Depot wants ~$400 for one 12" elbow. 
https://www.homedepot.com/p/DURA-12-in-Schedule-40-PVC-45-Degree-Elbow-SxS-417-120/203224395
https://www.homedepot.com/p/DURA-12-in-Schedule-40-PVC-45-Degree-Elbow-SxS-417-120/203224395
besides Beta6a whose specs are like my 6CX, are there any reasonable sized XKi alignments for Visaton's BG20? (this makes 5 plus years of asking - lol - I don't currently have hornresp, etc.)
BG20 has a large Vas from its low mass and high compliance, plus motor strength is only "meh"
For a low priced FR of good size in an XKi, 10FR300 might be the winner (?)
Def_Driver ‘Beta 6A’ | Eminence 6” speaker 4.5mm xmax
Sd=129.9cm2
Fs=123Hz
Mms=11g
Qms=3.46
Qes=0.66
Re=5.18 ohm
BL=8.13Tm
Le=0.43mH
Vas=3.51L
Def_Driver ‘BG20’ | Visaton 8” speaker 2mm xmax (3mm w. 1/4 gap height added)
Sd=213cm2
Fs=38Hz
Mms=10g
Qms=3.47
Qes=0.51
Re=6.2ohm
BL=6.1Tm
Le=0.8mH
Vas=110L
BG20 has a large Vas from its low mass and high compliance, plus motor strength is only "meh"
For a low priced FR of good size in an XKi, 10FR300 might be the winner (?)
Def_Driver ‘Beta 6A’ | Eminence 6” speaker 4.5mm xmax
Sd=129.9cm2
Fs=123Hz
Mms=11g
Qms=3.46
Qes=0.66
Re=5.18 ohm
BL=8.13Tm
Le=0.43mH
Vas=3.51L
Def_Driver ‘BG20’ | Visaton 8” speaker 2mm xmax (3mm w. 1/4 gap height added)
Sd=213cm2
Fs=38Hz
Mms=10g
Qms=3.47
Qes=0.51
Re=6.2ohm
BL=6.1Tm
Le=0.8mH
Vas=110L
On the use of RS270P-4 with the Mark Audio 7 MS in WAW, the sensitivity of the 10-inch woofers at around 91 seems to work well with the 7 MS which is around 86. I recall Dave from Planet 10 suggesting this is about the difference needed for the two to gel well, and they really do, certainly with the low pass at around 115Hz. Not sure what it should be optimally but the less voice I hear from the RS270P-4, the better, seemingly.
Just wondering, if I do decide to add a tweeter (which Im not yet convinced is necessary) what sensitivity should that be compared with the full range driver?
Just wondering, if I do decide to add a tweeter (which Im not yet convinced is necessary) what sensitivity should that be compared with the full range driver?
Is there a decent XKi alignment for either of these two drivers ? BG20 has a favorable qts, but Vas is rather large.
I have a coax like Beta 6A - is that better in a 0,43X15 than an Xki?
Def_Driver ‘Beta 6A’ | Eminence 6” speaker 4.5mm xmax
Sd=129.9cm2
Fs=123Hz
Mms=11g
Qms=3.46
Qes=0.66
Re=5.18 ohm
BL=8.13Tm
Le=0.43mH
Vas=3.51L
BG20 is a reasonably good driver at a low price
Def_Driver ‘BG20’ | Visaton 8” speaker 2mm xmax (3mm w. 1/4 gap height added)
Sd=213cm2
Fs=38Hz
Mms=10g
Qms=3.47
Qes=0.51
Re=6.2ohm
BL=6.1Tm
Le=0.8mH
Vas=110L
I have a coax like Beta 6A - is that better in a 0,43X15 than an Xki?
Def_Driver ‘Beta 6A’ | Eminence 6” speaker 4.5mm xmax
Sd=129.9cm2
Fs=123Hz
Mms=11g
Qms=3.46
Qes=0.66
Re=5.18 ohm
BL=8.13Tm
Le=0.43mH
Vas=3.51L
BG20 is a reasonably good driver at a low price
Def_Driver ‘BG20’ | Visaton 8” speaker 2mm xmax (3mm w. 1/4 gap height added)
Sd=213cm2
Fs=38Hz
Mms=10g
Qms=3.47
Qes=0.51
Re=6.2ohm
BL=6.1Tm
Le=0.8mH
Vas=110L
Finally picked up some user friendly #6x⅝" Phillips pan head screws for rear panels of my K6/XKi speakers w/PA130s. After I am sure I won't be removing the panels for a while i will hide the zinc plated screws with a spray of matte black. I added felt to most surfaces in rear chambers and am quite pleased with the result. At least for my ears the boominess is gone.
got a couple of Eminence 8 inch back when they were selling for $15 new each shipped.
Maybe one or two could make a punchy XKi boombox? Q is kinda high but
Vas is only 14 liters. It would not need to go "low" as a boombox - just low enough to give some semblance of bass and some punch in a reasonable to carry size.
Def_Driver ‘Eminator 1508’ | Eminence Chinese made 8 inch car woofer, Qts=0.59,3.3mm xmax
Sd=214.1cm2
Fs=82.68
Mms=17g
Qms=2.98
Qes=0.74
Re=6.7
BL=8.95T-M
Le=0.68mH
Vas=14L
Maybe one or two could make a punchy XKi boombox? Q is kinda high but
Vas is only 14 liters. It would not need to go "low" as a boombox - just low enough to give some semblance of bass and some punch in a reasonable to carry size.
Def_Driver ‘Eminator 1508’ | Eminence Chinese made 8 inch car woofer, Qts=0.59,3.3mm xmax
Sd=214.1cm2
Fs=82.68
Mms=17g
Qms=2.98
Qes=0.74
Re=6.7
BL=8.95T-M
Le=0.68mH
Vas=14L
Attachments
The melamine foam sponges come in standard 20mm thick pieces. So that’s what I used. The foam core is standard dollar store 3/16in thick stuff on the backside of the aperture. Then I covered the foam core with about 3mm thick felt. But the thickness is not important. 5mm can work too.
https://www.diyaudio.com/forums/ful...itio-karlson-6th-bandpass-92.html#post5763125
https://www.diyaudio.com/forums/ful...itio-karlson-6th-bandpass-92.html#post5763125