xrk971 suggests a 24 liter "XKi" for FE206 - -start at this post:
XKi - X's ab initio Karlson 6th Order Bandpass
basic details
XKi FOR FE206EN 24 Liter air-space total. 80/20 rear chamber to front chamber split.
4.8 liter front chamber - - - 19.2 liter rear chamber
Interal width = 10 inches. Internal height = 15 inches. Internal depth ~10 inches
Cavity depth at top = 4 inches Vent = 10 inches wide by 0.75" high by 10 inches long.
Aperture to just "touch" the speaker at its surround..
I don't know how it would play in GregB's Karlsonator8 - that cabinet is tuned to about 42Hz and I don't have one. It might be very good against a back wall (?)
Here's the plan for the Karlsonator8 - there's a much larger image "somewhere" in these threads
FE206/EN will play in small regular Karlson type. I've had it in a mini K-15, 1954 K12, a little K-coupler with curved reflector and a 1950's K8 . FE206EN was a lot of fun in the old K12 as there was adequate bass strength.
Here's the plan for the 1954 Karlson Twelve aka "Karlsonette" (the k8 had not yet been introduced)
http://i.imgur.com/ZMGQve3.png
If you use a subwoofer, then you could go down to about "K10" size and could make it like a scaled down K12 with 10 degree forwards cant port panel . I would probably use a single vent rather than distribute slits - although those can "sound good". Make the port a bit large for adjustments. Don't use a front shelf.
perhaps X will chime in with suggestions.
0.62 scale K15 with FE206EN - I think I've heard FE206 play better than in this one so that's why I suggest the K12 style front chamber
here's the curved panel cabinet which ran FE206EN - nice midrange - - K-guru Carl Neuser prefers curved reflectors but he uses higher aspect. Its shown loaded with an Audio Nirvana Super8.
Its just a little smaller than the 0.62 scale K15. I tried 3 sets of apertures - one traditional with radial arc, a much tighter aperture at the top, and the fast opening one below. FE206EN played clear on operatic voices with all three - its a good K-driver. I do like the sound of this faster aperture. 18mm Baltic Birch made it pretty solid. My 0.62 scale K15 above (made of 15mm BB) could use a brace on its rear panel.
The 1956 (I think) K12 which was presented as a plan in July 1958 Popular Mechanics could be scaled to bring its rear chamber down to around 1 cubic foot. I would probably use a single port and a full width rear shelf to tune it. The rear shelf mainly to add some lower port boundary. The slit vent may sound fine - it only noticeably distorts on sine.
K12 plan from Popular Mechanics, July 1958
https://i.pinimg.com/736x/c2/3f/60/c23f60c61f82ef19cf2a38dcb67514d1--cgi.jpg
Sometime in the 1960's, Karlson offered a version of the K12 with a blank port panel. That apparently had instructions on drilling holes for particular drivers of its day. There were factory drilled units with a 12 -hole distributed port. Some speaker probably were suggested to run without any port. It had a 30 degree baffle and brought back the full width rear shelf.
In the Netherlands, what we in the US call "The Dutch K12" became popular. In
contrast to Karlson's wheezy slits, this take had very large horizontal openings.
I assume the front aperture brought tuning back down into the mid 60 Hertz region (?)
and like other K, legendary for making a lot of sound with almost imperceptible cone motion.
Here's its plan its also been scaled downwards. I'd like to have one with a fully removable port panel for experiments vs other ports.
http://home.planet.nl/~ulfman/images/Plans/new12in.gif
Also, you could scale this 6.5" cabinet up for an 8. The aperture could
have a narrow extension going to the top
look at the upper aperture on my K18 - if that's too wide on the 8, then something
funky might happen
XKi - X's ab initio Karlson 6th Order Bandpass
basic details
XKi FOR FE206EN 24 Liter air-space total. 80/20 rear chamber to front chamber split.
4.8 liter front chamber - - - 19.2 liter rear chamber
Interal width = 10 inches. Internal height = 15 inches. Internal depth ~10 inches
Cavity depth at top = 4 inches Vent = 10 inches wide by 0.75" high by 10 inches long.
Aperture to just "touch" the speaker at its surround..
I don't know how it would play in GregB's Karlsonator8 - that cabinet is tuned to about 42Hz and I don't have one. It might be very good against a back wall (?)
Here's the plan for the Karlsonator8 - there's a much larger image "somewhere" in these threads
FE206/EN will play in small regular Karlson type. I've had it in a mini K-15, 1954 K12, a little K-coupler with curved reflector and a 1950's K8 . FE206EN was a lot of fun in the old K12 as there was adequate bass strength.
Here's the plan for the 1954 Karlson Twelve aka "Karlsonette" (the k8 had not yet been introduced)
http://i.imgur.com/ZMGQve3.png
If you use a subwoofer, then you could go down to about "K10" size and could make it like a scaled down K12 with 10 degree forwards cant port panel . I would probably use a single vent rather than distribute slits - although those can "sound good". Make the port a bit large for adjustments. Don't use a front shelf.
perhaps X will chime in with suggestions.
0.62 scale K15 with FE206EN - I think I've heard FE206 play better than in this one so that's why I suggest the K12 style front chamber
here's the curved panel cabinet which ran FE206EN - nice midrange - - K-guru Carl Neuser prefers curved reflectors but he uses higher aspect. Its shown loaded with an Audio Nirvana Super8.
Its just a little smaller than the 0.62 scale K15. I tried 3 sets of apertures - one traditional with radial arc, a much tighter aperture at the top, and the fast opening one below. FE206EN played clear on operatic voices with all three - its a good K-driver. I do like the sound of this faster aperture. 18mm Baltic Birch made it pretty solid. My 0.62 scale K15 above (made of 15mm BB) could use a brace on its rear panel.
The 1956 (I think) K12 which was presented as a plan in July 1958 Popular Mechanics could be scaled to bring its rear chamber down to around 1 cubic foot. I would probably use a single port and a full width rear shelf to tune it. The rear shelf mainly to add some lower port boundary. The slit vent may sound fine - it only noticeably distorts on sine.
K12 plan from Popular Mechanics, July 1958
https://i.pinimg.com/736x/c2/3f/60/c23f60c61f82ef19cf2a38dcb67514d1--cgi.jpg
Sometime in the 1960's, Karlson offered a version of the K12 with a blank port panel. That apparently had instructions on drilling holes for particular drivers of its day. There were factory drilled units with a 12 -hole distributed port. Some speaker probably were suggested to run without any port. It had a 30 degree baffle and brought back the full width rear shelf.
In the Netherlands, what we in the US call "The Dutch K12" became popular. In
contrast to Karlson's wheezy slits, this take had very large horizontal openings.
I assume the front aperture brought tuning back down into the mid 60 Hertz region (?)
and like other K, legendary for making a lot of sound with almost imperceptible cone motion.
Here's its plan its also been scaled downwards. I'd like to have one with a fully removable port panel for experiments vs other ports.
http://home.planet.nl/~ulfman/images/Plans/new12in.gif
Also, you could scale this 6.5" cabinet up for an 8. The aperture could
have a narrow extension going to the top
look at the upper aperture on my K18 - if that's too wide on the 8, then something
funky might happen
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Look at Steve Schell's comment on the Karlson enclosure ("K15"). Steve is part of "COGENT" (along with Rich Drysdale) who manufacture very high end field coil horn systems.
RE: I'm still standing up for the Karlson enclosure - Steve Schell - High Efficiency Speaker Asylum
a piece on COGENT back in 2006
Cogent Field Coil Horn Speakers
RE: I'm still standing up for the Karlson enclosure - Steve Schell - High Efficiency Speaker Asylum
a piece on COGENT back in 2006
Cogent Field Coil Horn Speakers
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Karlson's official "K18"
from Karlson's brochure's K18 dimensions, I'm reasonably sure it was directly scaled ~1.2:1 from K15 - at least the exterior form. That makes it a bit larger than the Cetic Gause 5181 K18
BTW, the Gauss 5181 below has a faster, more open aperture than the one normally seen and in plan form
KARLSON'S K18
CETEC GAUSS 5181 100lb cabinet with wide aperture
Here's a relative recent build of a 5181 cabinet (loaded with JBL18) - note its aperture vs the one above.
For a given inner vent size, the tighter aperture will, of course, tune the system somewhat lower than the
fast expanding aperture. Subjectively, there's a chance the fast aperture may sound better with some speakers.
from Karlson's brochure's K18 dimensions, I'm reasonably sure it was directly scaled ~1.2:1 from K15 - at least the exterior form. That makes it a bit larger than the Cetic Gause 5181 K18
BTW, the Gauss 5181 below has a faster, more open aperture than the one normally seen and in plan form
KARLSON'S K18
CETEC GAUSS 5181 100lb cabinet with wide aperture
Here's a relative recent build of a 5181 cabinet (loaded with JBL18) - note its aperture vs the one above.
For a given inner vent size, the tighter aperture will, of course, tune the system somewhat lower than the
fast expanding aperture. Subjectively, there's a chance the fast aperture may sound better with some speakers.
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Question about K15 drivers
Hi Freddi, I tried to get myself invited to Carl's to hear some Karlsons, but he said that his system is not well set up now and he is busy. He told me the first time I spoke to him that he would look around and see what extra parts he had. He said that he has some Transylvania tubes, but no 15in drivers. I am not interested in the tubes right now.
I found a local guy who rebuilds drivers. He has pairs of TAD 1601, JBL 2220a and LE15A, EV 15W, Altec 421 and 423, and Yamaha Jay 6132.
Of course the TADs would be interesting, but they are expensive.
If trying to keep costs down, and trying to find the best K15 drivers, it seems that the JBL 2220a drivers would work (very low 2 mm X-max and low 0.2 Qt). I think that this driver has an alnico magnet.
The other options are the Altec 421 or 423. I read somewhere that the 423 driver was made when Altec was trying to cheapen their drivers, if so, then the Altec 421 might be the better choice of these two.
What do you think Freddi? I saw that at one time that you picked up some JBL 2220a drivers. Did you like them?
Hi Freddi, I tried to get myself invited to Carl's to hear some Karlsons, but he said that his system is not well set up now and he is busy. He told me the first time I spoke to him that he would look around and see what extra parts he had. He said that he has some Transylvania tubes, but no 15in drivers. I am not interested in the tubes right now.
I found a local guy who rebuilds drivers. He has pairs of TAD 1601, JBL 2220a and LE15A, EV 15W, Altec 421 and 423, and Yamaha Jay 6132.
Of course the TADs would be interesting, but they are expensive.
If trying to keep costs down, and trying to find the best K15 drivers, it seems that the JBL 2220a drivers would work (very low 2 mm X-max and low 0.2 Qt). I think that this driver has an alnico magnet.
The other options are the Altec 421 or 423. I read somewhere that the 423 driver was made when Altec was trying to cheapen their drivers, if so, then the Altec 421 might be the better choice of these two.
What do you think Freddi? I saw that at one time that you picked up some JBL 2220a drivers. Did you like them?
-not sure if I ran 2220H in K15 - and did run one briefly in an X15 knockoff. Altec 421 are very good in K15 IIRC (I've got some 421 and 421-LF laying around) - it helps to use masking tape or something to tame the aluminum dustcap.
back a month ago, one could have picked up P-Audio BM 15CXA with their BMD440 compression drivers from Loudspeakersplus for $99 each. I imagine those would have been as good or better than a 2220H* plus make a whole usable system. (Folks on this forum tend to prefer by far little fullrange or even such things as 12LTA to coaxial woofer)
(2220H with ferrite motor was well behaved in the little X15 clone cabinet - 2220H = a light, curvilinear cone - some cone "cry" at its breakup peak - maybe the dustcap - the "A" version might sound prettier with it alnico motor)
(I'd like to have an extra Transylvania Tube)
back a month ago, one could have picked up P-Audio BM 15CXA with their BMD440 compression drivers from Loudspeakersplus for $99 each. I imagine those would have been as good or better than a 2220H* plus make a whole usable system. (Folks on this forum tend to prefer by far little fullrange or even such things as 12LTA to coaxial woofer)
(2220H with ferrite motor was well behaved in the little X15 clone cabinet - 2220H = a light, curvilinear cone - some cone "cry" at its breakup peak - maybe the dustcap - the "A" version might sound prettier with it alnico motor)
(I'd like to have an extra Transylvania Tube)
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since a K12 with tight saw-blade height horizontal slit vents produces strong overtones when driven by sine-wave, could it act with music like the MaxxBass and other pyschoacoustic bass generators?
Here's a graph I made of a Maxxbass with a small (14 cubic foot) folded bass horn and JBL2220 some time ago. The Maxxbass kicked H2 and H3 up 20 some dB. Also, I think it gave about a 6dB low end boost.
I like clean (sine playing) vents on Karlson but have to admit the skit vent can sound very good.
what's your thoughts on this matter? K12 with typical speakers running in the mid 90dB-100dB sensitivity are pretty well limited to upper bass work for starters so there's little fundamental in the first place.
General LF boost of Maxxbass - a rough comparison with
freezing RTA with it on vs off:
MaxxBass effects on harmonics of a single tone:
Here's a graph I made of a Maxxbass with a small (14 cubic foot) folded bass horn and JBL2220 some time ago. The Maxxbass kicked H2 and H3 up 20 some dB. Also, I think it gave about a 6dB low end boost.
I like clean (sine playing) vents on Karlson but have to admit the skit vent can sound very good.
what's your thoughts on this matter? K12 with typical speakers running in the mid 90dB-100dB sensitivity are pretty well limited to upper bass work for starters so there's little fundamental in the first place.
General LF boost of Maxxbass - a rough comparison with
freezing RTA with it on vs off:
MaxxBass effects on harmonics of a single tone:
Curved Reflectors - What's your take ?
its interesting how Carl builds his little "regular" K- it has a smooth, heavily shellacked ellipse based reflector, vented by a gap "above" the reflector, and sports a laminated maple veneer K-tube.
fwiw I would consider extending the aperture on this K below all the way up to the top with a tapered
narrow slit - not too wide. If you scale this to an 8 or 10 it might be close to what Carl Neuser builds.
(Its based upon one of his speakers)
I have a "tall K8" but its front chamber is pretty much like Karlson's K8 with the upper panel extended in height. I've recently bored a 3" hole at the top of that panel and need to compare response and impedance vs the regular
"Karlsonette styled" horizontal port. something looked odd with the top port and my Nirvana stamped frame Super8 both with input Z and response.
what's your opinion on curved reflectors and top porting in Ks? I have a K18 about 42 inches tall, 16 inches deep and about 22 inches wide with a curved reflector - It sounds quite good with just slotted pipe tweeter to extend the 18" woofer.
its interesting how Carl builds his little "regular" K- it has a smooth, heavily shellacked ellipse based reflector, vented by a gap "above" the reflector, and sports a laminated maple veneer K-tube.
fwiw I would consider extending the aperture on this K below all the way up to the top with a tapered
narrow slit - not too wide. If you scale this to an 8 or 10 it might be close to what Carl Neuser builds.
(Its based upon one of his speakers)
I have a "tall K8" but its front chamber is pretty much like Karlson's K8 with the upper panel extended in height. I've recently bored a 3" hole at the top of that panel and need to compare response and impedance vs the regular
"Karlsonette styled" horizontal port. something looked odd with the top port and my Nirvana stamped frame Super8 both with input Z and response.
what's your opinion on curved reflectors and top porting in Ks? I have a K18 about 42 inches tall, 16 inches deep and about 22 inches wide with a curved reflector - It sounds quite good with just slotted pipe tweeter to extend the 18" woofer.
"HAK"
here's one of Carl Neuser's earlier "high aspect Karlson" textboxes. Details were removable so different ports, port position, rear lowpass gap, tapers, front shelf deflector and front chamber reflector could be evaluated. Carl is a stanch proponent the curved reflectors per the final installment of Karlson's "Acoustic Transducers" patent.
With my crude HAK8 , similar in bulk to a Karlson12 and both loaded with W8-1772, the skinny, taller box had 2-5dB less output in the 110-220Hz region than Karlson's 1954 K12. What might be the reasons for that observation?
here's one of Carl Neuser's earlier "high aspect Karlson" textboxes. Details were removable so different ports, port position, rear lowpass gap, tapers, front shelf deflector and front chamber reflector could be evaluated. Carl is a stanch proponent the curved reflectors per the final installment of Karlson's "Acoustic Transducers" patent.
With my crude HAK8 , similar in bulk to a Karlson12 and both loaded with W8-1772, the skinny, taller box had 2-5dB less output in the 110-220Hz region than Karlson's 1954 K12. What might be the reasons for that observation?
with the horizontal port right above the speaker, my HAK8 didn't seem to have a real LF advantage over the K12. I can't remember how careful I was with regards to having both cabinets in the same spot (and same with mic placement) I've not played with that cabinet since cutting a 3" hole near the top of the slant board. An initial impedance plot looked very odd with my AN8. I'll try the W8-1772 which is still limber. Nirvana's surround goop seems to dry, stiffen and raised fs by a half octave from ~41 when first got the speakers to the mid 60's. (That's another plus for FE206EN)
It might require a short duct on the 3" hole to tune things for the HAK8 (?) - where do you think I should set tuning? 60? - lower ?
It might require a short duct on the 3" hole to tune things for the HAK8 (?) - where do you think I should set tuning? 60? - lower ?
Question for xrk971. If one is to use Mark Audio's Alpair 12P in a K - Which K suits it best overall? Would it be a Karlsonator? How would it play in GregB's Karlsonator6 which has Fb ~60Hz? Would it be lost in a stock Karlsonator8? What can be done with the original K concept ? How about a well thought out XKi ?
Def_Driver "ALpair12P" | ~6.5 in. Full Range driver from Mark Audio
Sd=147.41cm2
Fs=42.15
Mms=10.217g
Qms=1.981
Qes=0.333
Re=7.000
BL=7.540T-M
Le=0.054mH
Vas=43.060L
Def_Driver "ALpair12P" | ~6.5 in. Full Range driver from Mark Audio
Sd=147.41cm2
Fs=42.15
Mms=10.217g
Qms=1.981
Qes=0.333
Re=7.000
BL=7.540T-M
Le=0.054mH
Vas=43.060L
Hi Freddi,
I ran this sim a long time ago - yes, a 0.67x scale Karlsonator is best for the A12P. It will get about 93dB sensitivity and F3 of about 48Hz.
X
another kuestion - for a given lower Q driver and regular K as in the form of 115BK, what changes to the original scheme could help tame a peak which can occur? (see area in red oval) - does one add a resonator to the front chamber?
https://i.imgur.com/YZemfus.jpg
oddly, its not noticeable with 115BK indoors - or my KK-audio boxes with EV15B - and the bass, although high cutoff, does
not sound "hollow" when a K-tube treble is added to the little 4.3 cubic foot K-box
that peak can get out of hand sometimes - kinda weird - it doesn't sound crazy in a slit vent K12 either
loaded with old spec B102 ( that driver measures Qts ~0.23)
https://i.imgur.com/YZemfus.jpg
oddly, its not noticeable with 115BK indoors - or my KK-audio boxes with EV15B - and the bass, although high cutoff, does
not sound "hollow" when a K-tube treble is added to the little 4.3 cubic foot K-box
that peak can get out of hand sometimes - kinda weird - it doesn't sound crazy in a slit vent K12 either
loaded with old spec B102 ( that driver measures Qts ~0.23)
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