The vent was scaled by 0.35x of whatever the K15 plan shows. If I recall that was about 1.13in wide x about 2.50in tall or thereabouts. I never fully blocked the vent as I needed all the bass extension help I could get - you can feel the pulse of air shooting out of the vent on kick drums. I made an insert to reduce the CSA somewhat and also introduce extra length. This marginally increased bass extension by maybe 2Hz and not worth it for the loss in output. I need to find a 6.5in driver with 0.3 Qts and fs around 50 to 70Hz. That would work well I think to get a 100Hz extension on a 0.35x.
midrange sensitivity would drop with this driver but it might work https://www.madisoundspeakerstore.c...-6-7/silver-flute-w17rc38-08-6-1/2-wool-cone/
this? http://www.powerbassusa.com/xpro-6-65-mid-range-driver
http://www.techronics.com/caraudio_...bwoofer.html?gclid=CP2nzZKIt8ICFQmRaQodzXcA8Q
this? http://www.powerbassusa.com/xpro-6-65-mid-range-driver
http://www.techronics.com/caraudio_...bwoofer.html?gclid=CP2nzZKIt8ICFQmRaQodzXcA8Q
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hey X - for some reason I could see those audioportal.su images today = a couple of links from that thread required signing in so could only get the K-tube thumbnails.
the Karlsonator like cabinet was for a high qts driver - I didn't catch the driver for the tapered cabinet - there's a Faerber inspired K-tube - its interesting to see independent research
Àêóñòèêà Karlson.
Lomo 4a28 fullrange
the Karlsonator like cabinet was for a high qts driver - I didn't catch the driver for the tapered cabinet - there's a Faerber inspired K-tube - its interesting to see independent research
Àêóñòèêà Karlson.
Lomo 4a28 fullrange
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here's an ancient mini K15 for 8 inch speaker stuffed with the current 10 inch Eminence B102. Port is 4.25"x2.625" and overall shelf length ~7". Rear shelf gap ~2", front shelf gap ~1.75" - fb is ~68Hz. External dims sans front molding are 18.7"H x ~13.7"W x 11.25"D A round piezo works as a helper for the Eminence but it could run coaxial, or 10" with compression driver on a K-tube. I think its close to one size discussed with XRK971 and should work with a sub as 2.1
with a thick front gasket, I kinda like the small cutout - it might be sized to shade the pleated surround.
with a thick front gasket, I kinda like the small cutout - it might be sized to shade the pleated surround.
hey XRK971 - my K above is very close in size to your 0.55 sim - in real world response, do you think the LF rolloff with a P-Audio SN10C will be perhaps 10Hz higher than the sim you made? I'm pretty sure its a usable size with the later version of B102 but I don't want to pay $95 for a second moderate motor B102. The goal is to get the impression of a good horn rig in a mini package for HT fronts and the TQWT sub will do the _.1 duty
it would be interesting to hear what you think of say an inexpensive PRV compression driver with K-tube vs your ESS Heil - the Heil goes an octave lower and had a very "open" character which didn't always blend well with their mediocre woofers. A K-tube on a mini-K could be pretty cool.
SN10C in 0.55 scale K15
SN10C has a 2.5" coil with 2.8mm physical overhang
it would be interesting to hear what you think of say an inexpensive PRV compression driver with K-tube vs your ESS Heil - the Heil goes an octave lower and had a very "open" character which didn't always blend well with their mediocre woofers. A K-tube on a mini-K could be pretty cool.
SN10C in 0.55 scale K15
SN10C has a 2.5" coil with 2.8mm physical overhang
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hey XRK971 - my K above is very close in size to your 0.55 sim - in real world response, do you think the LF rolloff with a P-Audio SN10C will be perhaps 10Hz higher than the sim you made? I'm pretty sure its a usable size with the later version of B102 but I don't want to pay $95 for a second moderate motor B102. The goal is to get the impression of a good horn rig in a mini package for HT fronts and the TQWT sub will do the _.1 duty
it would be interesting to hear what you think of say an inexpensive PRV compression driver with K-tube vs your ESS Heil - the Heil goes an octave lower and had a very "open" character which didn't always blend well with their mediocre woofers. A K-tube on a mini-K could be pretty cool.
SN10C in 0.55 scale K15
SN10C has a 2.5" coil with 2.8mm physical overhang
I had a 0.43x scale with a predicted 100Hz and it matched measurment. This was with an 8in B&C coax. It depends on the driver fs, if the fs is above the fb and its is a low Qts driver - the model over predicts the bass extension. That happened to me with a mid driver on 0.35x.
interesting - assuming SN10C's fs is ballpark, it matches the tuning of the old mini K15 - a lot of these 10's have fs around 65-70Hz - could go with anywhere from 0.6 to .66 scale for this 10cx - got to make up mind so kutter can build - its either a mini K15 set or Kalsonator 8s this time around - the Karlsonators would go a lot deeper and stand on their own
one interesting combo to me would be the two mini-K15 using 10" plus say a reasonably compact woofer/subwoofer which can reach say 35-40Hz with good strength. A modest K-tube tweeter using a PRV D280Ti would be good as would the same driver on Beta 10cx or my P-Audio 10cx as one of the neo CD were ruined in shipping. A little commercial sub would work ok and a diy effort could be better with larger dynamic concerns. The system could do duty for music, HT and small stage gigs.
btw, I still have this speaker which could act as a 40Hz helper woofer for the .1 part http://www.volvotreter.de/downloads/Edgar-Monolith-Horn-01.jpg
btw, I still have this speaker which could act as a 40Hz helper woofer for the .1 part http://www.volvotreter.de/downloads/Edgar-Monolith-Horn-01.jpg
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deciding upon size for the sattelite
0.6 scale K15 preliminary drawings by TheJessMan based on an old diy K-coupler made for an 8" fullrange
with such a long front shelf, I'd imagine not a lot of highs reach the upper front chamber compared to no front shelf. The shelf in this case does get fb around 68Hz
0.6 scale K15 preliminary drawings by TheJessMan based on an old diy K-coupler made for an 8" fullrange
with such a long front shelf, I'd imagine not a lot of highs reach the upper front chamber compared to no front shelf. The shelf in this case does get fb around 68Hz
That shelf on front looks awfully long. It would also limit how effective the K aperture is at reducing resonances and it might be a large surface for a front reflection cancellation on the highs. I would make it smaller - scaled accordingly from K15. Best thing is to leave it flat and make interchangeable front shelves screwed on with a few bolts. Then you can test - this part is very hard to simulate accurately as there are 3d effects. So I can't really offer much from my model in akabak.
going by the 1954 K15 spec, a 0.6 scale coupler would have a 2.4" gap and the tighter spec from 1956 "changeover", ~2" gap from front shelf edge to wings. It'll be interesting to see how fb is altered from 68Hz on this old mini with B102 and ~1.75" front gap. If the wings aren't removable then it may be difficult to attach the front shelf pieces - I bet neo disc magnets recessed flush and epoxied would suffice for the front attachment(s). btw, this old coupler with its 1.75" front shelf gap seems to sound pretty good whether a Sammi fullrange or the current spec Eminence B102 so I think it may work out well for a sub-assisted system.
K15's side view from January 1954 Radio and TV News - plus Don Drenner's article used a four inch gap
K15's side view from January 1954 Radio and TV News - plus Don Drenner's article used a four inch gap
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question for X - - is there an optimal port placement for high aspect (tall) Karlson couplers? in the coupler below the vent is 12" wide by 3/4" wide and tunes quite high - it's bounded on the lower edge by a 2.75" rear shelf. How might things change if the port is say round, and moved up towards the top? - how about if near the middle of the enclosure height? - is there one spot which works better overall? For some reason the apparent tuning with my Nirvana Super8 seems even higher than the other cabinet with a Sammi fullrange. Plugging most of the vent on the Nirvana box (leaving maybe one square inch), gave fb in the 70's and condition of the 2nd Z peak amplitude much larger than the first - normally its the other way around - is the high aspect of the rear chamber exerting considerable 1/4 wave action?
the Karlsonator series seems a lot better/less tricky than this particular try
this box in inches is 13.5W x 12D x 28T
the Karlsonator series seems a lot better/less tricky than this particular try
this box in inches is 13.5W x 12D x 28T
I extended the upper port boundary so now its a regular slot port about 3/4" tall by 12" wide by 3" deep - AN8 has a rising on-axis behavior so it may take mild BSC to get more subjective LF punch. Mids and treble are good. When a hold saw arrives, I may try moving the vent upwards as with my nice K18 below.
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do not know if this is the right place to ask this but I spent the last few days relearning the truth that in modelling simplicity is best for checking out trends.
Any way I found DCR enclosures properly sized can give the boost shelf that XRK971 mentioned. In fact for TC9FD you can get a 5dB boost from about 80Hz to 250Hz.
Is this part of the attraction of the Karlson's because if it is you should be able to tune for individual speakers.
Any way I found DCR enclosures properly sized can give the boost shelf that XRK971 mentioned. In fact for TC9FD you can get a 5dB boost from about 80Hz to 250Hz.
Is this part of the attraction of the Karlson's because if it is you should be able to tune for individual speakers.
part of the attraction = improved overall sound quality vs direct radiator; reduced cone excursion - the originals could be voiced by altering the inner port area, adding inner De-Q-ing vent holes, and adjusting the rear lowpass gap area. The first Karlson 12 (aka "Karlsonette" at the time as the 8 inch cabinet had not yet been sold) introduced in the fall of 1954 had a movable bar on its rear panel to adjust the rear lowpass gap. The original 12 and 15 inch enclosures can have beautiful midrange quality depending upon driver. The second K12 which was featured in July 1958 Popular Mechanics, featured a split rear shelf and distributed slit vents. That type of vent whether in a Karlson or another enclosure can introduce high vent velocities, and distortion when driven with pure sine wave. It seems little problem with music or with things like bass guitar.
here's the effect upon input impedance when moving the damping bar on the 1954 Karlson Twelve
here's the effect upon input impedance when moving the damping bar on the 1954 Karlson Twelve
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