It seems like it can work well in a 0.87x scaled K15. Very good near 100dB punch at 50Hz.
hi X, here's Kappa 12A's specs - its a good little woofer for only an 80oz magnet slug and should take goodly power peaks safely
which scale of K15 might it like the best overall?
Nominal Diameter12"
Power Handling (RMS)450 Watts
Power Handling (max)900 Watts
Impedance8 ohms
Frequency Response62 to 4,200 Hz
Sensitivity99.3 dB 1W/1m
Voice Coil Diameter3"
Magnet Weight80 oz.
Thiele-Small Parameters
Resonant Frequency (Fs)45 Hz
DC Resistance (Re)5.41 ohms
Voice Coil Inductance (Le)0.77 mH
Mechanical Q (Qms)7.76
Electromagnetic Q (Qes)0.28
Total Q (Qts)0.27
Compliance Equivalent Volume (Vas)4 ft.³
Mechanical Compliance of Suspension (Cms)0.3 mm/N
BL Product (BL)15.2 Tm
Diaphragm Mass Inc. Airload (Mms)42g
Maximum Linear Excursion (Xmax)3.2 mm
Surface Area of Cone (Sd)519.5 cm²
which scale of K15 might it like the best overall?
Nominal Diameter12"
Power Handling (RMS)450 Watts
Power Handling (max)900 Watts
Impedance8 ohms
Frequency Response62 to 4,200 Hz
Sensitivity99.3 dB 1W/1m
Voice Coil Diameter3"
Magnet Weight80 oz.
Thiele-Small Parameters
Resonant Frequency (Fs)45 Hz
DC Resistance (Re)5.41 ohms
Voice Coil Inductance (Le)0.77 mH
Mechanical Q (Qms)7.76
Electromagnetic Q (Qes)0.28
Total Q (Qts)0.27
Compliance Equivalent Volume (Vas)4 ft.³
Mechanical Compliance of Suspension (Cms)0.3 mm/N
BL Product (BL)15.2 Tm
Diaphragm Mass Inc. Airload (Mms)42g
Maximum Linear Excursion (Xmax)3.2 mm
Surface Area of Cone (Sd)519.5 cm²
Not substantially different than DeltaPro12-A.
I can attest these parameters hit very hard in
full sized 1955RE-K15. Cone control was much
better than vented box, but still wasn't quite
enough XMAX for 300W bass guitar in drop D...
Nominal Diameter 12"
Power Handling (RMS) 400 Watts
Power Handling (max) 800 Watts
Impedance 8 ohms
Frequency Response 52 to 4,500 Hz
Sensitivity 99.2 dB 1W/1m
Voice Coil Diameter 2.5"
Magnet Weight 80 oz.
Resonant Frequency (Fs) 51 Hz
DC Resistance (Re) 5.71 ohms
Voice Coil Inductance (Le) 0.84 mH
Mechanical Q (Qms) 7.56
Electromagnetic Q (Qes) 0.37
Total Q (Qts) 0.35
Compliance Equivalent Volume (Vas) 2.9 ft.³
Mechanical Compliance of Suspension (Cms) 0.21 mm/N
BL Product (BL) 15.3 Tm
Diaphragm Mass Inc. Airload (Mms) 48g
Maximum Linear Excursion (Xmax) 4.6 mm
Surface Area of Cone (Sd) 532.4 cm²
I'm thinking you have 1.4mm less XMAX than I did,
looser compliance, and lower resonance. Probably
going to upset your XMAX limit way before power...
Maybe with a high pass filter like a tapped horn.
Such thunderous chest pounding, you sometimes
forget it doesn't really offer much below 55Hz.
I can attest these parameters hit very hard in
full sized 1955RE-K15. Cone control was much
better than vented box, but still wasn't quite
enough XMAX for 300W bass guitar in drop D...
Nominal Diameter 12"
Power Handling (RMS) 400 Watts
Power Handling (max) 800 Watts
Impedance 8 ohms
Frequency Response 52 to 4,500 Hz
Sensitivity 99.2 dB 1W/1m
Voice Coil Diameter 2.5"
Magnet Weight 80 oz.
Resonant Frequency (Fs) 51 Hz
DC Resistance (Re) 5.71 ohms
Voice Coil Inductance (Le) 0.84 mH
Mechanical Q (Qms) 7.56
Electromagnetic Q (Qes) 0.37
Total Q (Qts) 0.35
Compliance Equivalent Volume (Vas) 2.9 ft.³
Mechanical Compliance of Suspension (Cms) 0.21 mm/N
BL Product (BL) 15.3 Tm
Diaphragm Mass Inc. Airload (Mms) 48g
Maximum Linear Excursion (Xmax) 4.6 mm
Surface Area of Cone (Sd) 532.4 cm²
I'm thinking you have 1.4mm less XMAX than I did,
looser compliance, and lower resonance. Probably
going to upset your XMAX limit way before power...
Maybe with a high pass filter like a tapped horn.
Such thunderous chest pounding, you sometimes
forget it doesn't really offer much below 55Hz.
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Freddi,
The Kappa12A works beautifully in an 0.8x scale K15. With a 45Hz 24dB HPF you can get at most 20v into it before hitting xmax. The response looks great though.
Response at 2.83v:
xmax:
Max SPL:
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good !! thanks for the simulation - I miss my 0.8 scale cabinets built 20 years ago - still want the 0.55 scale with 10" = too many cabinets and very little room
Karlson in the 1954 Radio Television News article, warned against scaling K15 by 0.8 - perhaps to make for better sales of the upcoming K12 - my old graphs showed 0.8 to be smooth.
with a Pyle 1298 (~same as Kappa 12A) in K12, there's no problem with 200 watt peaks on drum albums. Karlson made K12 with slit vents - possibly to get a better match with weaker motors as that was the age of separate cabinets and speakers and possibly as he did not worry about the vent's ability to carry sine wave.
this was originally made with two 3"x3" ABS ducts but K15 style vent proved superior - at the time it ran a Sammi 12 woofer and was tried with JBL 123
Karlson in the 1954 Radio Television News article, warned against scaling K15 by 0.8 - perhaps to make for better sales of the upcoming K12 - my old graphs showed 0.8 to be smooth.
with a Pyle 1298 (~same as Kappa 12A) in K12, there's no problem with 200 watt peaks on drum albums. Karlson made K12 with slit vents - possibly to get a better match with weaker motors as that was the age of separate cabinets and speakers and possibly as he did not worry about the vent's ability to carry sine wave.
this was originally made with two 3"x3" ABS ducts but K15 style vent proved superior - at the time it ran a Sammi 12 woofer and was tried with JBL 123
An externally hosted image should be here but it was not working when we last tested it.
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But the 1954 plans (see attachment) said that an 0.8x (12/15) scale model had been built, although there was a resonant peak and because they could not solve it at that point the 12/15 scale was not recommended. I wonder what resonant peak they are talking about? It may be that at the smaller size, the front K-aperture distance to the cone may match another resonance and cause a problem? This cannot be modeled in Akabak as it is a lumped element model. A 3d FEM can do it though.
my old flabby chest needs hundreds of watts..
The Kappa 12A can probably handle 8mm cone displacement (xmech limit is 11.5mm) without damage (w/ 40Hz 24dB HPF). That's what happens with 200 watts applied, and here is the resulting output. Ouch, my ear drums!
Here is the impulse response:
It should give a great rendition of drums if that is what you are looking for, or perhaps can double as a defibrulator
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I think I've come close to 200 watt peaks with Steve Clarke's "Solo Drum" album in a K12 - cone movement within plus or minus 3mm xmax.
Karlson deleted K15's matching shelf in all the small couplers - for a new build the shelf could be kept stubby and stack on pieces to adjust and examine.
I don't remember a response problem from the front shelf in a 0.8 scale K15 but do remember, getting very close to the cabinet and shelf did some segregation of highs with more lows prominent "above the shelf"
Imageshack lost most of my graphs - here's a remnant snapshot of the 0.8 scale with two duct vents in-room D123 wants a large reflex box
maybe you can kobble a 0.8 scale K15 from pink foam board
Karlson deleted K15's matching shelf in all the small couplers - for a new build the shelf could be kept stubby and stack on pieces to adjust and examine.
I don't remember a response problem from the front shelf in a 0.8 scale K15 but do remember, getting very close to the cabinet and shelf did some segregation of highs with more lows prominent "above the shelf"
Imageshack lost most of my graphs - here's a remnant snapshot of the 0.8 scale with two duct vents in-room D123 wants a large reflex box
maybe you can kobble a 0.8 scale K15 from pink foam board
one reason to explore a K10 is that I think it may have just as much output from 70 up as a K12
here's a K10 size coupler with 30 degree baffle and 12 degree port board - no upper reflector loaded with a Delta 10A vs a standard 6-slit vent K12 loaded with a Pyle PYM1298. That Pyle was built by Eminence and is about the same as a Kappa12A other than claiming a 96 or 98 ounce magnet slug
with a little luck and perhaps experiment before a final vent, a small K10 might be pretty impressive and have better fill around 300Hz - its already strong - Delta 10A by itself under pink noise makes some ugly sounds - but its relatives have been used for Econowave builds with no complaints
my room is probably pulling down the 200Hz region with the cabinets in this position - I always mark the spot with tape to ensure the same place for graphing.
here's my existing K10 with Delta10a next to a vintage factory K15
here's a K10 size coupler with 30 degree baffle and 12 degree port board - no upper reflector loaded with a Delta 10A vs a standard 6-slit vent K12 loaded with a Pyle PYM1298. That Pyle was built by Eminence and is about the same as a Kappa12A other than claiming a 96 or 98 ounce magnet slug
with a little luck and perhaps experiment before a final vent, a small K10 might be pretty impressive and have better fill around 300Hz - its already strong - Delta 10A by itself under pink noise makes some ugly sounds - but its relatives have been used for Econowave builds with no complaints
my room is probably pulling down the 200Hz region with the cabinets in this position - I always mark the spot with tape to ensure the same place for graphing.
here's my existing K10 with Delta10a next to a vintage factory K15
An externally hosted image should be here but it was not working when we last tested it.
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Freddi,
I am looking at pushing the scale of an 8in class driver K15 down to a very compact 0.43x while maintaining 100Hz extension in order to use as PA tops. The K15 topology even when scaled down this small seems to provide the most effective cone excursion control and enable excellent power handling for pro audio use. Thanks for the data on your 10in scale K.
I am looking at pushing the scale of an 8in class driver K15 down to a very compact 0.43x while maintaining 100Hz extension in order to use as PA tops. The K15 topology even when scaled down this small seems to provide the most effective cone excursion control and enable excellent power handling for pro audio use. Thanks for the data on your 10in scale K.
a K-tube plus woofer would be good - could be mounted internally
An externally hosted image should be here but it was not working when we last tested it.
that 1.875" diameter x 7.25" long K-tube is a clone of one from a 1960's Karlson X15 which used an University Sound compression driver with a 15" CTS woofer. This was Carl's first interpretation of the X15 size - the ports were made adjustable on this test box - you can see the left port with spacers - also there was an adjustable rear lowpass shelf for study. Later, Carl used a fully curved reflector saying that was an improvement. Several X15 speakers have surfaced over the years, one with a smaller 1.25" diameter slotted pipe waveguide. That tube above measures a bit rough in places but sounds good and "fast" - - for smooth response, a one inch pipe 5.3" long with a half-ellipse slot works very well. The X15 type properly made should be "high end" - probably an "X12" would make a very good system heart and less expensive than some coaxial.
look at the one inch diameter pipe's response - it would have been even smoother without the short stub
- in its range, the K-tube can sound more natural than a CD waveguide on hi hats and cymbals - I have little desire to use horn or CD waveguide for certain speakers - btw, the reason for the 12KHz cutoff in the graphs below is that was a CD8 Eminence "type I" compression driver with an aluminum diaphragm - the later titanium driver goes higher.
don't forget Greg B.'s "Karlsonator" - that approach is very flexible and gives a more extended low end than traditional Karlson cabinets. The traditional are great for punch in a small size.
look at the one inch diameter pipe's response - it would have been even smoother without the short stub
- in its range, the K-tube can sound more natural than a CD waveguide on hi hats and cymbals - I have little desire to use horn or CD waveguide for certain speakers - btw, the reason for the 12KHz cutoff in the graphs below is that was a CD8 Eminence "type I" compression driver with an aluminum diaphragm - the later titanium driver goes higher.
don't forget Greg B.'s "Karlsonator" - that approach is very flexible and gives a more extended low end than traditional Karlson cabinets. The traditional are great for punch in a small size.
An externally hosted image should be here but it was not working when we last tested it.
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