it should play in a K12 as BG20 works - also, Thejessman's test of Karlsonator 8 was with a BG20
perhaps XRK971 would suggest a vent size and placement for the 1960's K12 - -also, what he thinks of the 30 degree chamber vs one more shallow - what do we get with the canted port board vs K15/Karlsonette's front chamber shape? FWIW I would make a single port slightly large so it could be adjusted - the same for the rear lowpass gap.
I believe this K12 was offered with a black port board and instructions
on drilling a distributed hole array port according to driver - the cabinets already
drilled were sold with a Tannoy Red coax
perhaps XRK971 would suggest a vent size and placement for the 1960's K12 - -also, what he thinks of the 30 degree chamber vs one more shallow - what do we get with the canted port board vs K15/Karlsonette's front chamber shape? FWIW I would make a single port slightly large so it could be adjusted - the same for the rear lowpass gap.
I believe this K12 was offered with a black port board and instructions
on drilling a distributed hole array port according to driver - the cabinets already
drilled were sold with a Tannoy Red coax
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Most cabs for this driver are very large, I was hoping a Karlson type would be a smaller option without sacrificing bass. If you could run a sim that would be great!
How did the BG20 work out in the Karlsonator 8? If I recall the sims did not look good.
The K12 looks interesting -- does it have good bass?
I assume BG20 from thejessman's outdoor Karlsonator 8 graph (red trace), extended deeper than in a K12 (?) Karlsonator 8's tuning is lower.
a well placed and not too aggressive helper tweeter might help BG20 with K12 - BG20 pretty much on axis might suffice without any help with ear height driver in a tall MLTL - I didn't feel BG20 to be "muted" in K12 - it just didn't have the brightness say of FE206EN.
here's a higher resolution graph of Jessman's outdoor session of BG20 in Karlsonator 8 and Karlsonator 12
- I think he only had the stubs lined with carpet felt - proper fill of the stub with damping material should reduce
the narrow dips
a well placed and not too aggressive helper tweeter might help BG20 with K12 - BG20 pretty much on axis might suffice without any help with ear height driver in a tall MLTL - I didn't feel BG20 to be "muted" in K12 - it just didn't have the brightness say of FE206EN.
here's a higher resolution graph of Jessman's outdoor session of BG20 in Karlsonator 8 and Karlsonator 12
- I think he only had the stubs lined with carpet felt - proper fill of the stub with damping material should reduce
the narrow dips
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hi xrk971 - - do you have any further thoughts as to which 6.5" might work well in the 0.35X K15? If the vent is blocked, would response (assuming the driver's TS allowed ~flat response with a sealed back chamber) remain reasonably smooth ? - or might it depend upon backwave fill thought the vent? proportion-wise, a 6.5" speaker in a 0.35 size is like an 18" in K15.
hey xrk971 - - lets say I want to reduce my 0.62 x K15 for a 10 to a somewhat smaller size and not lose significant performance - can the baffle angle be pulled up to reduce front chamber size and a bit cut "here and there" in overall dimensions and come up with a very good and punchy "K10" ? - the goal is to get a powerful "hit" in the smallest box, retain good dispersion and sound quality. Seems like a 10" is just about the smallest size speaker which can play decently loud midbass with acceptable excursion levels.
Freddi,
It's doable what you suggest but I am not sure reducing front chamber matters that much. I am guessing that the bass will go to about 90Hz in the scale you suggest. Is that good enough? If you need more maybe an XKi for a 10in driver?
It's doable what you suggest but I am not sure reducing front chamber matters that much. I am guessing that the bass will go to about 90Hz in the scale you suggest. Is that good enough? If you need more maybe an XKi for a 10in driver?
60-70Hz pretty solid would be great - if it doesn't overly compromise power handling - low enough cutoff to give kick drum and lower tom drums a good representation. Kappa12a is good as I have those unused plus its close cousin pym1298. We know from sim that a 0.8 K15 should be pretty good with Kappa12. I like the 10" size a lot as know it can play well but Delta10a has quite a peak - guess a proper xover should take care of its audibility. I have one new spec Eminence B102 - not real hot in the mids, 2-Beyma 10G200 never loaded and going to waste. The new XKi would go up against a 12" folded midbass horn and would be nice for the little K to hit ~120dB up close.
Freddi,
I actually ran a sim of the Kappa 12A for you way back when - I found the sim results on my hard drive. Anyhow, I did re-run it given the request for max punch and 60-70Hz reach. If you just put it in a standard K12, it would be quite happy and get you 97dB bass level with -3dB at 48Hz. However, if you scaled the box by 0.67x in height and depth but by 0.80x in width you get something perhaps closer to what you are looking for with about 99dB and f3 of 63Hz:
I actually ran a sim of the Kappa 12A for you way back when - I found the sim results on my hard drive. Anyhow, I did re-run it given the request for max punch and 60-70Hz reach. If you just put it in a standard K12, it would be quite happy and get you 97dB bass level with -3dB at 48Hz. However, if you scaled the box by 0.67x in height and depth but by 0.80x in width you get something perhaps closer to what you are looking for with about 99dB and f3 of 63Hz:
Attachments
You speak of a K12 only 16 inches tall.
giving you 2 inches for upper chamber.
Given the ancedotal advantages of taller
K-coupler, even to extending a stub, does
scaling 0.67x height make any sense???
giving you 2 inches for upper chamber.
Given the ancedotal advantages of taller
K-coupler, even to extending a stub, does
scaling 0.67x height make any sense???
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Well, that's how the model sees it. It's really about volumes for the chambers and not "height" for a K15 as it operates as a 6th (sometimes 8th) order series band pass. So, I squashed the height to reduce the volume. If one wanted to keep the height so it looks normal, I suppose you can reduce front to back depth, but that is hard to put in my model.
For the Karlsonator, it is a TL, so length makes a difference.
Someone suggested a cheap $60 car audio 15in woofer - the Eminator for a K. Well this thing in a K15 absolutely kicks butt like the thread title, and does so perhaps better than any I have seen. 120dB at 54Hz with25 volts (-24dB HPF at 35Hz);
Nice!
Nice!
those Eminator 15 are $34.50 shipped directly from Eminence's online shop. Check the other Eminators too
http://www.eminence.com/speakers/speaker-detail/?model=EM_2515
- thanks for the little "K12" - don't know if the real world LF corner would be as good as the sim
here's an Eminence/Pyle pym1298 - pretty much the same speaker as Kappa12a, outdoors in a Karlsonette copy with
a small vent hacked into its board and regular vent blocked - look at the LF corner - why do such deep dips occur? bounce? the mic was laying on the ground IIRC - larger vents seem to "fill" the first dip better in general - does that make sense?
fb here was around 53Hz - normal K12 tuning is in the low 60's - the tight slit vent probably goes into rectification
at relatively low drive levels and becomes a "fan"
here's X's prediction of Kappa12a in a 0.8 scale K15 - I'd be happy if it could reach F3 ~60-65Hz
http://www.eminence.com/speakers/speaker-detail/?model=EM_2515
- thanks for the little "K12" - don't know if the real world LF corner would be as good as the sim
here's an Eminence/Pyle pym1298 - pretty much the same speaker as Kappa12a, outdoors in a Karlsonette copy with
a small vent hacked into its board and regular vent blocked - look at the LF corner - why do such deep dips occur? bounce? the mic was laying on the ground IIRC - larger vents seem to "fill" the first dip better in general - does that make sense?
fb here was around 53Hz - normal K12 tuning is in the low 60's - the tight slit vent probably goes into rectification
at relatively low drive levels and becomes a "fan"
here's X's prediction of Kappa12a in a 0.8 scale K15 - I'd be happy if it could reach F3 ~60-65Hz
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It makes a difference if the aperture comes to a narrow cusp vs a slot. Wider aperture pushes it up to 100 Hz.
this old now-discarded diy 0.8 scale K15 which was built before I ever saw a K12 plan has the desired cusp aperture
am picking up another DeltaPro8A - not sure if a wise choice but will make a pair - although rated at 97.8dB, its about 3-4dB less sensitive in its upper range than the little, low-mass and excellent 6.5" L Cao F6.
is there a good K alignment for DeltaPro8A? - it could be used just as a K--midrange in a mid-sensitivity 3-way K system or an "X8" satellite speaker with a K-tube w. one inch compression driver mounted on the reflector board. Power handling on transients should be ok with the 2" diameter coil and 59oz magnet - there is no attempt to flatten inductive coil impedance rise.
this is what an "X8" would look like using the 1955 K8 form and a 5.3" long K-tube
DeltaPro8a
Resonant Frequency (Fs)69 HzDC Resistance (Re)5.6=40 ohms
Voice Coil Inductance (Le)0.82 mHMechanical Q (Qms)6.43
Electromagnetic Q (Qes)0.22Total Q (Qts)0.22
Compliance Equivalent Volume (Vas)0.65 ft.³Mechanical Compliance of Suspension (Cms)0.28 mm/N
BL Product (BL)14.1 TmDiaphragm Mass Inc. Airload (Mms)19g
Maximum Linear Excursion (Xmax)3 mmSurface Area of Cone (Sd)218.2 cm²
is there a "best" cavity shape for a midrange K using 8" drivers? one wants to get the benefits and not invite large amplitude swings.
F6 would probably make a very nice mid-fullrange K but might need a lossy t-line rear chamber or sealed.
JLH has apparently used DeltaPro8A for midbass duty where it would shine.
btw, F6 is quite extended on-axis and a nice/musical little speaker
is there a good K alignment for DeltaPro8A? - it could be used just as a K--midrange in a mid-sensitivity 3-way K system or an "X8" satellite speaker with a K-tube w. one inch compression driver mounted on the reflector board. Power handling on transients should be ok with the 2" diameter coil and 59oz magnet - there is no attempt to flatten inductive coil impedance rise.
this is what an "X8" would look like using the 1955 K8 form and a 5.3" long K-tube
DeltaPro8a
Resonant Frequency (Fs)69 HzDC Resistance (Re)5.6=40 ohms
Voice Coil Inductance (Le)0.82 mHMechanical Q (Qms)6.43
Electromagnetic Q (Qes)0.22Total Q (Qts)0.22
Compliance Equivalent Volume (Vas)0.65 ft.³Mechanical Compliance of Suspension (Cms)0.28 mm/N
BL Product (BL)14.1 TmDiaphragm Mass Inc. Airload (Mms)19g
Maximum Linear Excursion (Xmax)3 mmSurface Area of Cone (Sd)218.2 cm²
is there a "best" cavity shape for a midrange K using 8" drivers? one wants to get the benefits and not invite large amplitude swings.
F6 would probably make a very nice mid-fullrange K but might need a lossy t-line rear chamber or sealed.
JLH has apparently used DeltaPro8A for midbass duty where it would shine.
btw, F6 is quite extended on-axis and a nice/musical little speaker
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the recent "K10" based on ~0.62 scale K15 with Beta10cx is pretty punchy - its about 20.4" tall, 13.875" wide and 11.3" deep - oddly, when I block about half the vent's area, I don't think the response changes a lot on the mic, but the punch and large sound goes away on plucked and bowed bass viola. With a lower Q 10 it might be possible to shrink the cabinet a bit more. Also it could be designed possibly to use an internal 1" diameter K-tube if the aperture is wide enough where the tube would meet. I used Eminence's later CX crossover values with Erse and cheapo Chinese "Audiophiler" caps (which measure well FWIW) - neither tweeter polarity produced any deep null with APT50. I think ASD1001 would be good and tougher as the 3.3uF/0.35mH highpass actually goes pretty low on the compression driver.
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