(this is a segment of the upcoming "Karlson Compendium"
John Karlson and Wayne Green completed the famous "K15" prototype in the summer of 1951 and it was introduced commercially at the big names Hi Fi show in the Hotel New Yorker, Fall 1952.
K15 had a long run, produced in the thousands, but as time moved forward and the playback mediums of vinyl and tape heading away from mono to two channel, plus the acoustic suspension revolution of Edgar Vilchur and Henry Kloss, K15 was too cumbersome in pairs for small rooms.
Karlson with the 1964-65 World's Fair and K15 with Electro-Voice 15TRX supplying sound for a number of exhibits including Disney.
It was late 1965 when AUDIO Magazine's Annual Directory announced Karlson's X15 speaker. It featured a custom CTS woofer, much like a K33 but with less excursion and higher sensitivity. Also, the first model used a 3 inch cone speaker which fire into a custom Karlson asymmetric ("klam") lens. Subsequent models featured a slotted pipe with a one inch format compression driver made by University Sound. Two different diameter slotted pipe waveguide have been seen so Karlson was certainly experimenting Also, one X15 for organ use had a conventional horn in its front chamber, pointing up at a angle.
X15 with nominal dimensions of 28" tall, 20" wide and about 14" deep, had roughly a bulk of only 4.3 cubic feet - just one cubic foot larger than Karlson's 12 inch ("K12") model, and only about 57 percent the bulk of K15, so a stereo pair really could fit many rooms.
At ~57 percent bulk of K15, and fixed sensitivity 15 inch speaker, X15 would have its low frequency cutoff about a half octave higher than that of K15. Nonetheless, like a good K12 setup, percussion transient are impressive and cone excursion in the passband reduced vs a 12 inch speaker.
Also, X15 incorporated a 3 panel approximation of an ellipse curve upper reflector. (That was covered as an improvement in Karlson's 2nd and final "Acoustic Transducers patent,, #3540544).
Sometime around 1980, a number of X15 size K-coupler appeared on the market. I think Karlson's widow sold rights to at least 5 companies
There was Transylvania Power Company, KK-Audio, Acoustic Control, Westwood, and a little company in Chicago, all producing pretty much the same cabinet.
With hindsight I wonder if these company's even knew there had been an X15 already with large port, pretty much what they ended up building and same with Cetec -Gauss when Karlson already had a "K18"
FWIW, I'd love to find someone who would make a nice pair of the wooden klam to try with say Faital Pro's 3FE22
John Karlson and Wayne Green completed the famous "K15" prototype in the summer of 1951 and it was introduced commercially at the big names Hi Fi show in the Hotel New Yorker, Fall 1952.
K15 had a long run, produced in the thousands, but as time moved forward and the playback mediums of vinyl and tape heading away from mono to two channel, plus the acoustic suspension revolution of Edgar Vilchur and Henry Kloss, K15 was too cumbersome in pairs for small rooms.
Karlson with the 1964-65 World's Fair and K15 with Electro-Voice 15TRX supplying sound for a number of exhibits including Disney.
It was late 1965 when AUDIO Magazine's Annual Directory announced Karlson's X15 speaker. It featured a custom CTS woofer, much like a K33 but with less excursion and higher sensitivity. Also, the first model used a 3 inch cone speaker which fire into a custom Karlson asymmetric ("klam") lens. Subsequent models featured a slotted pipe with a one inch format compression driver made by University Sound. Two different diameter slotted pipe waveguide have been seen so Karlson was certainly experimenting Also, one X15 for organ use had a conventional horn in its front chamber, pointing up at a angle.
X15 with nominal dimensions of 28" tall, 20" wide and about 14" deep, had roughly a bulk of only 4.3 cubic feet - just one cubic foot larger than Karlson's 12 inch ("K12") model, and only about 57 percent the bulk of K15, so a stereo pair really could fit many rooms.
At ~57 percent bulk of K15, and fixed sensitivity 15 inch speaker, X15 would have its low frequency cutoff about a half octave higher than that of K15. Nonetheless, like a good K12 setup, percussion transient are impressive and cone excursion in the passband reduced vs a 12 inch speaker.
Also, X15 incorporated a 3 panel approximation of an ellipse curve upper reflector. (That was covered as an improvement in Karlson's 2nd and final "Acoustic Transducers patent,, #3540544).
Sometime around 1980, a number of X15 size K-coupler appeared on the market. I think Karlson's widow sold rights to at least 5 companies
There was Transylvania Power Company, KK-Audio, Acoustic Control, Westwood, and a little company in Chicago, all producing pretty much the same cabinet.With hindsight I wonder if these company's even knew there had been an X15 already with large port, pretty much what they ended up building and same with Cetec -Gauss when Karlson already had a "K18"
FWIW, I'd love to find someone who would make a nice pair of the wooden klam to try with say Faital Pro's 3FE22
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Karlson X15's First Tweeter
used a 3 inch cone speaker, looking like some of the Quam brand tweeters of its day, but in an open back frame. A Styrofoam coffee cup was used as back chamber
The aperture appears to be radial arc - there were two 1/2" diameter holes spaced 2 1/2" apart.
It mounted to the lower panel of the 3-panel reflector.
used a 3 inch cone speaker, looking like some of the Quam brand tweeters of its day, but in an open back frame. A Styrofoam coffee cup was used as back chamber
The aperture appears to be radial arc - there were two 1/2" diameter holes spaced 2 1/2" apart.
It mounted to the lower panel of the 3-panel reflector.
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Freddi, is there any sketch of the small klam? Is it similar to the one I tried to design for 3D printing? My large printer is getting back online soon, so I should re-visit this little project and print it in full size with improvements so that it can actually be printed (or print it in two halves worst case).
you'll have to make a sketch. Its triangular, and the front either 7 inches in length (from David A. Young) or 6 inches (?) which was the dimension given for the one in the X15 pictures above. Width was 3.75" and the speaker baffle square so 3.75" x 3.75". The slot appears to have been radial arc based and there were two 0.5" vent holes spaced 2.5" apart center to center.
It should be interesting with your 3FE22.
It should be interesting with your 3FE22.
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Hi EddieT in today's market I'd look for a 15 inch driver with moving mass between 50 and 75 grams, a rising on axis response could be useful.
Although with significantly higher Qts than Karlson’s CTS 15” speaker, an Eminence Delta 15A may be a good match - it may have been the speaker John Lapaire preferred in a copy of X15 (just wrote to him - hopefully a reply)
https://www.eminence.com/pdf/Delta_15A.pdf
Kappa 15A should be good and kicky - I'm not sure how to deal with its peak - GregB said for some reason it was inaudible in K15 and certainly in the big "Artichoke" Burning Man horn.
https://www.eminence.com/pdf/Kappa_15A.pdf
The big port X15 had the same 3 panel reflector as my X15, but wider. Its port area was very close to that of the later Acoustic Control 115BK/BC2 K-coupler.
115BK is a very nice little cabinet which measures smooth and it tuned to about 53Hz.
FWIW I would consider building X15 size with a simple port board like "this" as drawn by TB46. Then again, Carl Neuser built X15 with a fully curved bent wood reflector and said that was an improvement in sound quality over the approximation.
Also, here's TB46's drawing of Acoustic Control's 115BK
Although with significantly higher Qts than Karlson’s CTS 15” speaker, an Eminence Delta 15A may be a good match - it may have been the speaker John Lapaire preferred in a copy of X15 (just wrote to him - hopefully a reply)
https://www.eminence.com/pdf/Delta_15A.pdf
Kappa 15A should be good and kicky - I'm not sure how to deal with its peak - GregB said for some reason it was inaudible in K15 and certainly in the big "Artichoke" Burning Man horn.
https://www.eminence.com/pdf/Kappa_15A.pdf
The big port X15 had the same 3 panel reflector as my X15, but wider. Its port area was very close to that of the later Acoustic Control 115BK/BC2 K-coupler.
115BK is a very nice little cabinet which measures smooth and it tuned to about 53Hz.
FWIW I would consider building X15 size with a simple port board like "this" as drawn by TB46. Then again, Carl Neuser built X15 with a fully curved bent wood reflector and said that was an improvement in sound quality over the approximation.
Also, here's TB46's drawing of Acoustic Control's 115BK
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Hey Pelanj and EddieT - does it look to you from the photos above that the tweeter klam is canted "forwards" ?
Here's the 3 panel X15 reflector - one can see that the back chamber seems to hang within the speaker baffle's cutout
I think, but am not sure that the little wood tweeter klam attached to the lower reflector panel (?)
Here's the 3 panel X15 reflector - one can see that the back chamber seems to hang within the speaker baffle's cutout
I think, but am not sure that the little wood tweeter klam attached to the lower reflector panel (?)
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To be honest, I am now completely confused on how it was mounted. Was it in front of the woofer on the top? Then the baffle normal would be actually pointing into the narrow part of the front slot? And I see my test model has the k-slot turned upside down
Edit: Fixed that.
Edit: Fixed that.
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Here's David A. Young's description from a 2001 post at Job Ulfman's Karlson Speaker forum which sounds like the mini klam was attached to the speaker baffle. Since David was familiar with Poppe and apparently, the Karlsons, perhaps his 7 inch measurement is the more accurate, assuming not varying from cabinet to cabinet. Its interesting that Poppe's X15 was tuned with such a resistive vent.
Date: 02/3/01 03:51:16 PM
Name: David A. Young
Email:
Subject: Re: Karlson X-15 1972 Model Organ SPKR.?
"I have a data sheet for the X-15 as well as plans drawn from
one of Martin Poppe's cabinets. I have heard the X-15 in a church
with Ann Karlson playing the organ. From what I can remember it
sounded very good. Martin's sounded strong in the lower midrange.
I still have one of the X-15 copies left. In the early eighties
I built 6 and sold them to Bass Guitar players. Great dispersion
and a fat bass sound. The original used a 15" stamped basket woofer with a 54 oz. square magnet, 2" voice coil, straight cone,
and doped 4 roll cloth surround. Kustom Electronics used a similar
speaker in its Bass Amplifiers. It is also similar to a Klipsh K-33.
The tweeter had a 3" cone with a styrofoam coffee cup on
the back. The tweeter coupler was triangular and 3 3/4" wide.
The front was 7" long, the back was 4", and the tweeter panel
was 3 3/4". There was a 1/2" hole on eighter side of the coupler
at the base. The slot was radial. The tweeter was fastened to the
baffle at the upper edge of the woofer cutout.
The reflector above the baffle was elliptical and made up of three panels. There is a short shelf on the rear of the first reflector parel. The port has
a board with 42, 3/8" holes in it. The box was 27 3/4" High,
19 5/8" Wide, and 14 1/8" Deep.
Dave"
Date: 02/3/01 03:51:16 PM
Name: David A. Young
Email:
Subject: Re: Karlson X-15 1972 Model Organ SPKR.?
"I have a data sheet for the X-15 as well as plans drawn from
one of Martin Poppe's cabinets. I have heard the X-15 in a church
with Ann Karlson playing the organ. From what I can remember it
sounded very good. Martin's sounded strong in the lower midrange.
I still have one of the X-15 copies left. In the early eighties
I built 6 and sold them to Bass Guitar players. Great dispersion
and a fat bass sound. The original used a 15" stamped basket woofer with a 54 oz. square magnet, 2" voice coil, straight cone,
and doped 4 roll cloth surround. Kustom Electronics used a similar
speaker in its Bass Amplifiers. It is also similar to a Klipsh K-33.
The tweeter had a 3" cone with a styrofoam coffee cup on
the back. The tweeter coupler was triangular and 3 3/4" wide.
The front was 7" long, the back was 4", and the tweeter panel
was 3 3/4". There was a 1/2" hole on eighter side of the coupler
at the base. The slot was radial. The tweeter was fastened to the
baffle at the upper edge of the woofer cutout.
The reflector above the baffle was elliptical and made up of three panels. There is a short shelf on the rear of the first reflector parel. The port has
a board with 42, 3/8" holes in it. The box was 27 3/4" High,
19 5/8" Wide, and 14 1/8" Deep.
Dave"
years ago I tried to mock it up in cardboard but did not have a strong 3" driver plus the back chamber obviously was larger than the truncated coffee cup
Being attached to the upper edge of the baffle is interesting. That baffle leans back from vertical ~ 23 degrees which means a lot of the tweeter's energy would have been bounced off the reflector and some fired at the narrowest part of the main aperture - right ? (the concept is konfusing)
Being attached to the upper edge of the baffle is interesting. That baffle leans back from vertical ~ 23 degrees which means a lot of the tweeter's energy would have been bounced off the reflector and some fired at the narrowest part of the main aperture - right ? (the concept is konfusing)
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something like "so" ? - be nice to have it drawn to scale. With a K-tube in the X15, there's a fair amount of energy
propagated at right angles to the slot plane which is also reflected from the 3 panel ellipse approximation reflector.
(Carl Neuser says a fully curved reflector is an improvement yet over the approximation)
propagated at right angles to the slot plane which is also reflected from the 3 panel ellipse approximation reflector.
(Carl Neuser says a fully curved reflector is an improvement yet over the approximation)
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Confused about mini-Klam positioning.
Hi freddi, looking at pelanj's 3D model in post #6, shouldn't the K-slot have the narrow end at the speaker, and the wide end away from the speaker? Oh, just saw pelanj's post #12, so that's fixed. Also, I can't get my head around how this is mounted in the Karlson enclosure. Is it mounted above the driver on the driver baffle board, partially overlapping the 15" driver? OK, just saw post #16, now, wouldn't it be better to have the big driver inserted from the back? Still somewhat confused. Help.
Hi freddi, looking at pelanj's 3D model in post #6, shouldn't the K-slot have the narrow end at the speaker, and the wide end away from the speaker? Oh, just saw pelanj's post #12, so that's fixed. Also, I can't get my head around how this is mounted in the Karlson enclosure. Is it mounted above the driver on the driver baffle board, partially overlapping the 15" driver? OK, just saw post #16, now, wouldn't it be better to have the big driver inserted from the back? Still somewhat confused. Help.
Hi TB46
I think the four inch side attached to the main speaker baffle - one can see the aperture of the tweeter klam pretty clear and the way
it hung a couple of inches below the woofer's nominal 13.3 inch cutout.
At first I thought this tweeter klam was titled forwards by bumping against the lowest reflector panel but guess the four inch sided flush against the upper part of the speaker baffle would work out correctly - look at the front view of the baffle with that Quam or whatever brand 3 inch speaker. Maybe those holes and ones unseen to the left held metal brackets to secure the little klam to the baffle.
How thick does the wood look to you ?
I think the four inch side attached to the main speaker baffle - one can see the aperture of the tweeter klam pretty clear and the way
it hung a couple of inches below the woofer's nominal 13.3 inch cutout.
At first I thought this tweeter klam was titled forwards by bumping against the lowest reflector panel but guess the four inch sided flush against the upper part of the speaker baffle would work out correctly - look at the front view of the baffle with that Quam or whatever brand 3 inch speaker. Maybe those holes and ones unseen to the left held metal brackets to secure the little klam to the baffle.
How thick does the wood look to you ?
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hi pelanj and TB46
- that is quite an angle considering X15's 23 degree baffle tilt. The highest F's would go pretty much "straight" down the klam and bounce off the reflector.
Amazingly enough, some high F stuff can get to and out of the narrowest portion of a K's aperture. The fact that is was considered to sound good as Ann Karlson's organ speaker is intriguing. I'd guess the 4 ohm version of 3FE22 would be one of the hotter 3 inch fullrange available today, and should be more comfortable with a low crossover point than 1 inch format compression drivers which reach 15-20KHz.
This 3 inch $12 LaVoce speaker is well made, has sturdy terminals and a hot on axis top end so would be my choice on the cheap side
(it sounds pretty good too)
LaVoce FSF030.70 3" Ferrite Full-Range Woofer 8 Ohm
- that is quite an angle considering X15's 23 degree baffle tilt. The highest F's would go pretty much "straight" down the klam and bounce off the reflector.
Amazingly enough, some high F stuff can get to and out of the narrowest portion of a K's aperture. The fact that is was considered to sound good as Ann Karlson's organ speaker is intriguing. I'd guess the 4 ohm version of 3FE22 would be one of the hotter 3 inch fullrange available today, and should be more comfortable with a low crossover point than 1 inch format compression drivers which reach 15-20KHz.
This 3 inch $12 LaVoce speaker is well made, has sturdy terminals and a hot on axis top end so would be my choice on the cheap side
(it sounds pretty good too)
LaVoce FSF030.70 3" Ferrite Full-Range Woofer 8 Ohm
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