Looks like the w8-2145 is not particularly liked. Just a thought Freddi are we asking the wrong question when want a smaller K speaker. I notice X mentioned a dual chamber bass reflex gives a different quality of bass. Others have mentioned the upper bass is much improved. The original K can be described as a dual chamber bass reflex.
Perhaps we can sort of answer this if you would like to try making a new box for one of the speakers you have-- l cao f6. According to X's model it should reach 40Hz and do 99dB in the passband but you will need a high pass filter to cut off frequencies below 40Hz because it could damage the speaker
Perhaps we can sort of answer this if you would like to try making a new box for one of the speakers you have-- l cao f6. According to X's model it should reach 40Hz and do 99dB in the passband but you will need a high pass filter to cut off frequencies below 40Hz because it could damage the speaker
a dual chamber reflex with no port damping will exhibit a mild notch not seen with the same Vb total single chamber reflex. Depending on tuning, I would imagine bass quality would have to improve. K15 has a rear lowpass gap of around 0.3*Sd for a 15 IIRC. I've seen the Karlsonette lowpass adjusted very tight -to maybe 0.2*Sd for a 12.
I just loaded the current Eminence B102 into a two cubic foot box and topped it with an APT150 tweeter. 2.5CF is about twice that of a K12's rear chamber, so it goes lower. It sounds weak on drum transients and organ dynamics compared to my K12 with a pym1298, topped by a K-tube. The perceived increase in dynamics with the K12 in the upper bass and lower midrange isn't just a frequency response result.
Karlson, when balanced so not too much cavity peak, etc, can be very good. i think if I ever have some more cabinets built, they will be K12 again - but not with the distributed slit port - although that can sound very good despite the inability to play sine waves cleanly.
I'd imagine that unpopular Tangband to be decent.
here's B102 run fullrange with a starter network for APT150 - - have one of my old B102 in a slit vent K12
I just loaded the current Eminence B102 into a two cubic foot box and topped it with an APT150 tweeter. 2.5CF is about twice that of a K12's rear chamber, so it goes lower. It sounds weak on drum transients and organ dynamics compared to my K12 with a pym1298, topped by a K-tube. The perceived increase in dynamics with the K12 in the upper bass and lower midrange isn't just a frequency response result.
Karlson, when balanced so not too much cavity peak, etc, can be very good. i think if I ever have some more cabinets built, they will be K12 again - but not with the distributed slit port - although that can sound very good despite the inability to play sine waves cleanly.
I'd imagine that unpopular Tangband to be decent.
here's B102 run fullrange with a starter network for APT150 - - have one of my old B102 in a slit vent K12
Thanks for your reply Freddi.
Without the K-coupler front chamber the double chamber reflex would be limited by cone excursion. In X's model adding the K-coupler front chamber appears to extend the sound level to 99dB at 5V drive.
If you are still game the speaker chamber would be 47 litres, the upper chamber would be 24.9 litres and the front chamber would be 41 litres. The vent between the speaker chamber and upper chamber would be 2 pieces of 5cmD pipe 4cm long. the vent between the upper chamber and front chamber would be a pipe 5cmD by 4cm long.
Without the K-coupler front chamber the double chamber reflex would be limited by cone excursion. In X's model adding the K-coupler front chamber appears to extend the sound level to 99dB at 5V drive.
If you are still game the speaker chamber would be 47 litres, the upper chamber would be 24.9 litres and the front chamber would be 41 litres. The vent between the speaker chamber and upper chamber would be 2 pieces of 5cmD pipe 4cm long. the vent between the upper chamber and front chamber would be a pipe 5cmD by 4cm long.
as you can see the l cao f6 requires a relatively large box. if you reduce the box size the passband would be reduced which is why i think the requirements of small box size and lower bass frequency might be mutually exclusive. Perhaps you might have a suitable speaker in mind that requires a smaller bass reflex box. Thanks for listening
so, your proposed 2145 K would have: "the speaker chamber would be 47 litres, the upper chamber would be 24.9 litres and the front chamber would be 41 litres. The vent between the speaker chamber and upper chamber would be 2 pieces of 5cmD pipe 4cm long. the vent between the upper chamber and front chamber would be a pipe 5cmD by 4cm long" - -that could be an interesting build. For less expensive 8" fullrange, there's not much available other than BetsyK, Audio Gradient's AX08 (I have one in an 1955 K12, and Visaton's BG20, which has doubled in price since its US introduction at Partsexpress a few years back.
Eminence's B102 seems to act similar to BG20 with regards to box requirements, is tough, but starts rolling off above 2KHz, so requires a tweeter of some sort. I don't seem to have a graph but Beta10cx shares the same basic cone
here's B102 again with APT150 sitting on top of the old 2.5 CF Burhoe box -No damping material in the box at the time of the graph - I just lined the box tonight so that part is acceptable
thejessman's Karlsonator8 with Visaton BG20 had decent response - so I'd expect speakers with similar parameters would work. Karlsonator8 tuned around 42Hz
B102 could use an internal K-tube tweeter
W8-2145 Fs-40Hz - Qts 0.44 Vas = 2.39 CF
BG20 Fs -38Hz - Qts 0.44 Vas = 3.88CF
B102 Fs -48Hz -Qts 0.39 Vas = 2.3 CF
Eminence's B102 seems to act similar to BG20 with regards to box requirements, is tough, but starts rolling off above 2KHz, so requires a tweeter of some sort. I don't seem to have a graph but Beta10cx shares the same basic cone
here's B102 again with APT150 sitting on top of the old 2.5 CF Burhoe box -No damping material in the box at the time of the graph - I just lined the box tonight so that part is acceptable
thejessman's Karlsonator8 with Visaton BG20 had decent response - so I'd expect speakers with similar parameters would work. Karlsonator8 tuned around 42Hz
B102 could use an internal K-tube tweeter
W8-2145 Fs-40Hz - Qts 0.44 Vas = 2.39 CF
BG20 Fs -38Hz - Qts 0.44 Vas = 3.88CF
B102 Fs -48Hz -Qts 0.39 Vas = 2.3 CF
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The Karlsonator is an interesting speaker. It is a version of TQWT so if I can get all parameters right speaker excursion is reduced by half. Unfortunately i am not as creative as X so I cannot always get it by trial and error. The normal K is easier. I just used vented volumes predicted by bass reflex programs and adjust the vents given.
I have done a few karlsonators in foam but somehow real drums as opposed to fake electronically generated drums don't sound quite right on them. This not too say karlsonators sound bad. in fact I enjoy them and they are well behaved below passband so i dont need to use an electronic highpass filter to protect the speakers. together with reduced excursion they should sound better than regular K's but so far I havent been too successful
I have done a few karlsonators in foam but somehow real drums as opposed to fake electronically generated drums don't sound quite right on them. This not too say karlsonators sound bad. in fact I enjoy them and they are well behaved below passband so i dont need to use an electronic highpass filter to protect the speakers. together with reduced excursion they should sound better than regular K's but so far I havent been too successful
would you share your method for making a regular Karlson by parameters? Is the original aspect usually the best? Can we sometimes treat them like an assisted 6th order reflex and apply boost at system tuning to flatten their response? Does front cavity shape matter with regards to resonance ? can certain shapes exacerbate dips? - How about port placement? (and need for port area) Is there a preferred/sweet spot Qts?
Its interesting Karlson, in his article for January 1954 Radio and Television News, warned against direct scaling of K15 by 0.8 for a 12" version. K12 was just coming out tha year and deleted the front shelf. I had a 0.8 scale K15 at on etime and thought it pretty good - the front shelf did seemed to keep some highs from reaching the upper part of the front chamber - it measured pretty well. If ? had one again, I'd start with a shorter front shelf then adjust that feature to see and hear effects.
Its interesting Karlson, in his article for January 1954 Radio and Television News, warned against direct scaling of K15 by 0.8 for a 12" version. K12 was just coming out tha year and deleted the front shelf. I had a 0.8 scale K15 at on etime and thought it pretty good - the front shelf did seemed to keep some highs from reaching the upper part of the front chamber - it measured pretty well. If ? had one again, I'd start with a shorter front shelf then adjust that feature to see and hear effects.
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I'll have to dig into my drum CD collection and give a listen to 12LTA in the Karlsonator12 versus perhaps 12LTA in an X15 semi-clone (its accurate other than the driver cutout for 15" speaker being moved 7/8" too high vs an original X15 speaker. It would be good if I can get the tuning around 55Hz. The X15 has around two cubic feet rear chamber, one cubic foot front. My other 12LTA was rubbing when the cone was pushed after a drop -maybe things are ok now - there was no visible frame damage nor bending.
I had the feeling the Karlsonator 12 was exhibiting good control down low - but its tuned about 37Hz. Perhaps its an illusion (?) I don't think excursion sims indicate anything special for K or K-nator. I have watched two tone mixed with 16Hz on the bottom of a reflex - cone movement was chaotic and fluttery (like sidebands). When the same test done on K15 which is tuned in the mid-upper 40's the movement looked more controlled and I could just about count the cycles. K15 can outperform some horns and imo, holds a special place in real world speaker approach.
I had the feeling the Karlsonator 12 was exhibiting good control down low - but its tuned about 37Hz. Perhaps its an illusion (?) I don't think excursion sims indicate anything special for K or K-nator. I have watched two tone mixed with 16Hz on the bottom of a reflex - cone movement was chaotic and fluttery (like sidebands). When the same test done on K15 which is tuned in the mid-upper 40's the movement looked more controlled and I could just about count the cycles. K15 can outperform some horns and imo, holds a special place in real world speaker approach.
the original Karlson aka "K15" is still IMO a top contender for agile and powerful bass - it will not go low but it will play jaw dropping transients which elude reflex and even a lot of horn designs. There is some pyscho-acoustic work going on too from the highs effect in the front chamber. For those who can't source a good coax, woofer plus K-tube and compression driver is an option.
What Karson varient for bass 50 - 250 hz?
I am thinking of using a variant of the Karlson design for bass. I will have a subwoofer for under 40 hz, and my plan is to have a horn for my Lowthers above 250 hz, or thereabouts.
The possible variants include:
K15
Karsonator 15
Karlflex 15
Kazba open baffle with perhaps dual 15s, push-pull
What do you guys think?
My room is 19 feet by 25 feet, so not small, but not real large either.
Retsel
I am thinking of using a variant of the Karlson design for bass. I will have a subwoofer for under 40 hz, and my plan is to have a horn for my Lowthers above 250 hz, or thereabouts.
The possible variants include:
K15
Karsonator 15
Karlflex 15
Kazba open baffle with perhaps dual 15s, push-pull
What do you guys think?
My room is 19 feet by 25 feet, so not small, but not real large either.
Retsel
K15 would have pretty powerful and adept bass transients with very little cone motion. K15 plays vocals, etc. very nicely.
I'm including the little X15 size and K-tube for those who might find use for such setups.
Going to "X15 size" (~57 percent K15's bulk) such as X15 or the Acoustic Control, you would have a good "midbass" horn substitute. This size is only about on cubic foot more external bulk than the K12. (K12 is also very capable from ~70Hz upwards when using a motor like Kappa12A)
Since TB46's Karlflex is about the same size as the 115BK,, here's a fudged sim of them. Fb for 115BK is about 52Hz - its rear chamber ~ 2 cubic foot, front chamber ! 1 cubic foot.
I don't know how close this is to reality without having a real Karlflex by TB46 in -hand. MMJ could sim the
effects of an extra chamber with akabak.
115BK would be only 13.5" deep if built without the wings inset - it may not be deep enough as built to accommodate a coax. A K-tube on top would sound very good. I also think a baffle at the K-tube's driver plane could be helpful. A one inch PVC/ABS. etc. pipe about 5.5" long with half ellipse based slot and 1/8" opening at the slot's beginning, ,makes a good K-tube.
~ground plane 115BK with EVM15L - 1/24 octave looked about as smooth - there was no damping
material at all in the cabinet
sine harmonic distortion for the little 115BK seemed reasonable - the port is sizable and doesn't not compress
115BK rough dimensions - its 19" wide inside - wings appear to be radial arc
A custom Transylvania K-coupler with their K-tube
Mrs. K, after John's death, issued multiple licenses to build K's - it seems Acoustic, KK-Audio, Westwood, Transylvania, and another company built "X15" size K-couplers. Its said that JBL purchased the patent too and threatened suits if production was not immediately shut down. "X15" was introduced for 1965 with advertised dimensions of 28"x20"x15". The first units featured a mini wood "asymmetric projector" K-coupler with 3" speaker as tweeter. That assembly was on the lower reflector panel. Karlson later used slotted pipes with compression drivers. X15 goes with his seconds and final installment of "Acoustic Transducers"
I think there are good Karlsonator15 possibilities at about the same bulk as K15 - the lower tuning of the K-nator would lose some punch. It might be good not to tune it below ~40Hz. X seems to have a good model for the Karlsonator.
dunno about the big Kazba
I'm including the little X15 size and K-tube for those who might find use for such setups.
Going to "X15 size" (~57 percent K15's bulk) such as X15 or the Acoustic Control, you would have a good "midbass" horn substitute. This size is only about on cubic foot more external bulk than the K12. (K12 is also very capable from ~70Hz upwards when using a motor like Kappa12A)
Since TB46's Karlflex is about the same size as the 115BK,, here's a fudged sim of them. Fb for 115BK is about 52Hz - its rear chamber ~ 2 cubic foot, front chamber ! 1 cubic foot.
I don't know how close this is to reality without having a real Karlflex by TB46 in -hand. MMJ could sim the
effects of an extra chamber with akabak.
115BK would be only 13.5" deep if built without the wings inset - it may not be deep enough as built to accommodate a coax. A K-tube on top would sound very good. I also think a baffle at the K-tube's driver plane could be helpful. A one inch PVC/ABS. etc. pipe about 5.5" long with half ellipse based slot and 1/8" opening at the slot's beginning, ,makes a good K-tube.
~ground plane 115BK with EVM15L - 1/24 octave looked about as smooth - there was no damping
material at all in the cabinet
sine harmonic distortion for the little 115BK seemed reasonable - the port is sizable and doesn't not compress
115BK rough dimensions - its 19" wide inside - wings appear to be radial arc
A custom Transylvania K-coupler with their K-tube
Mrs. K, after John's death, issued multiple licenses to build K's - it seems Acoustic, KK-Audio, Westwood, Transylvania, and another company built "X15" size K-couplers. Its said that JBL purchased the patent too and threatened suits if production was not immediately shut down. "X15" was introduced for 1965 with advertised dimensions of 28"x20"x15". The first units featured a mini wood "asymmetric projector" K-coupler with 3" speaker as tweeter. That assembly was on the lower reflector panel. Karlson later used slotted pipes with compression drivers. X15 goes with his seconds and final installment of "Acoustic Transducers"
I think there are good Karlsonator15 possibilities at about the same bulk as K15 - the lower tuning of the K-nator would lose some punch. It might be good not to tune it below ~40Hz. X seems to have a good model for the Karlsonator.
dunno about the big Kazba
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K15
So Freddi for 40 to ~250 hz or so, you would suggest a K15 for best dynamics, based on limited experience with some of these Karlson-related designs. Maybe others will chime in....
It would seem that the Karlson cabinet likes lower Q drivers with higher FS values. Thus, perhaps a 0.3 Qts and an FS around 40 hz or so? Do you think that something around 10 mm x-max would be fine?
Retsel
So Freddi for 40 to ~250 hz or so, you would suggest a K15 for best dynamics, based on limited experience with some of these Karlson-related designs. Maybe others will chime in....
It would seem that the Karlson cabinet likes lower Q drivers with higher FS values. Thus, perhaps a 0.3 Qts and an FS around 40 hz or so? Do you think that something around 10 mm x-max would be fine?
Retsel
if there were such a thing as a 15 with 10mm xmax with no more than 70g mms - then that might be Ok. It would take a kilowatt to drive it to that excursion. 3mm peak excursion is rarely exceeded with K15. (how powerful is your amp and what genre are covered?) A lower fs and low qts 15 speaker like vintage Altec 416 probably sounds "softer" than a 40Hz woofer like Eminence 15s.
Candidate 15 inch drivers
I listen to all kinds of stuff, from jazz to pop to rock to classical.
I surely won't use 10 mm xmax, but if the driver is designed for 10 mm xmax, then the distortion would be lower at 3 or 4 or 5 mm - at least that is my theory.
I have a Hafler P7000 amp which is 500 Watt/channel (I purchased it from Mike Bates aka Magnetar back in the day). But that amp might best be used for the subwoofer. I also have a pair of Audionics amps, which when bridged will put out about 250 watts/channel into 4 ohms - I was considering upgrading these and using them for the bass.
I looked through the Eminence webpage and most all the drivers are a little more then 70 grams. The Kappa lite is 84 grams, the Kappa 15A is 76 grams and the Kappa 15c is 77 grams. The Delta Pro 15 A is 60 grams, but with a 0.4 Qts.
Bert Doppenberg's BD15 drivers are 66 grams.
The Acoustic Elegance TD15 M woofers are 70 grams.
I can look into Altec 416 woofers too, but all are old stock, right?
What drivers would you use for a home environment?
Retsel
I listen to all kinds of stuff, from jazz to pop to rock to classical.
I surely won't use 10 mm xmax, but if the driver is designed for 10 mm xmax, then the distortion would be lower at 3 or 4 or 5 mm - at least that is my theory.
I have a Hafler P7000 amp which is 500 Watt/channel (I purchased it from Mike Bates aka Magnetar back in the day). But that amp might best be used for the subwoofer. I also have a pair of Audionics amps, which when bridged will put out about 250 watts/channel into 4 ohms - I was considering upgrading these and using them for the bass.
I looked through the Eminence webpage and most all the drivers are a little more then 70 grams. The Kappa lite is 84 grams, the Kappa 15A is 76 grams and the Kappa 15c is 77 grams. The Delta Pro 15 A is 60 grams, but with a 0.4 Qts.
Bert Doppenberg's BD15 drivers are 66 grams.
The Acoustic Elegance TD15 M woofers are 70 grams.
I can look into Altec 416 woofers too, but all are old stock, right?
What drivers would you use for a home environment?
Retsel
I'm a poor one to ask on drivers as tend to be cheap and buy cheap stuff - there's some P-Audio 15s on clearance at ~$90 each but see over at Speakerplans that it was considered to not be good above 500 (xmax isn't high either) P-Audio has a nearly unbelievable Qts figure of 0.16 for SN5B - that seems awfully low.
it would be good to ask the multi way and subwoofer forums for opinion as to what 15s would match (ask Pooh too)
it would be good to ask the multi way and subwoofer forums for opinion as to what 15s would match (ask Pooh too)
15 inch drivers for the Karlson
Thinking about this more, since I am not using the Karlson above 1000 hz, I probably don't need ultralight cones.
The webpage below compares and discusses the qualities of three different woofers.
15? Woofer Survey? A Tale Of Three Woofers Article By Jeff Poth
What the comparison revealed is that if not low passed, the very light cone BD15 is the best driver. However, with a 1000 hz low pass filter in place, the other woofers with somewhat heavier cones actually were better for reproducing bass with more impact.
Of course, choosing a woofer with a little heavier cone will reduce my ability to use the Karlson up high in case I want to do that.
I have Mike Bates' phone number somewhere (it is still good), maybe I will call him to see what he thinks. Also, as it turns out, Carl Neuser lives not too far from me. Maybe I can call him out of the blue, perhaps visit, and maybe he will share some words of wisdom with me.
Thinking about this more, since I am not using the Karlson above 1000 hz, I probably don't need ultralight cones.
The webpage below compares and discusses the qualities of three different woofers.
15? Woofer Survey? A Tale Of Three Woofers Article By Jeff Poth
What the comparison revealed is that if not low passed, the very light cone BD15 is the best driver. However, with a 1000 hz low pass filter in place, the other woofers with somewhat heavier cones actually were better for reproducing bass with more impact.
Of course, choosing a woofer with a little heavier cone will reduce my ability to use the Karlson up high in case I want to do that.
I have Mike Bates' phone number somewhere (it is still good), maybe I will call him to see what he thinks. Also, as it turns out, Carl Neuser lives not too far from me. Maybe I can call him out of the blue, perhaps visit, and maybe he will share some words of wisdom with me.
Carl should be a lot of fun to visit - if you do, say "hi" and take some notes on his Ks. For a real bargain, you could grab the last pair of P-Audio 15CXA from Loudspeakersplus at $99 each - shipping for the pair would run ~$32 to my area. I'd buy them, but have taxes to pay, fridge on the blink and a leaking main water line. 