Freddi,
I can run some sims to check this by adjusting aspect ratio while preserving volume. I think that because the K12 is a bandpass multi chamber reflex box - until the aspect ratio is long enough for it to switch to TL operation where the length of the upper or lower chamber is significant - there will be minimal effect. That is my guess but we will see. The K12 and K15 are very good from an efficiency standpoint in that they have a great coupling between the cone and air motion. I wonder how stretching it will affect this? Stretching it may impact CSA of the inner shelf vent and top chamber vent. That will modify coupling efficiency.
I can run some sims to check this by adjusting aspect ratio while preserving volume. I think that because the K12 is a bandpass multi chamber reflex box - until the aspect ratio is long enough for it to switch to TL operation where the length of the upper or lower chamber is significant - there will be minimal effect. That is my guess but we will see. The K12 and K15 are very good from an efficiency standpoint in that they have a great coupling between the cone and air motion. I wonder how stretching it will affect this? Stretching it may impact CSA of the inner shelf vent and top chamber vent. That will modify coupling efficiency.
can you also run the case where there's no front shelf? - that's the way most smaller couplers are made including Karlson's originals -- I think the goal of the high aspect K was to extend the bottom a bit and limit cavity peaking.
we can see in Fig.3 of Karlson's 1951 patent, whether built or not at that time, suggested a high aspect to the K-coupler. K15 was already finalized at that time and getting ready for production in 1952.
Carl's kid must had made HAKs starting 20 years ago
a proper HAK8 would probably be like this testbox by Carl with a laminated veneer K-tube
the reflector panel is fully curved like the SK6.5 which diyaudio member AmadeusMozart
made based on Carl's work - a K-tube is something most highly recommended.
my recent HAK8 came out ok - I think it may be a bit too tall - or the top piece not
at the best angle.
btw, some years back I had a guy make a Fig.4 of that patent - it really works to sound nice
Karlson envisioned violins made that way
we can see in Fig.3 of Karlson's 1951 patent, whether built or not at that time, suggested a high aspect to the K-coupler. K15 was already finalized at that time and getting ready for production in 1952.
Carl's kid must had made HAKs starting 20 years ago
An externally hosted image should be here but it was not working when we last tested it.
a proper HAK8 would probably be like this testbox by Carl with a laminated veneer K-tube
the reflector panel is fully curved like the SK6.5 which diyaudio member AmadeusMozart
made based on Carl's work - a K-tube is something most highly recommended.
An externally hosted image should be here but it was not working when we last tested it.
my recent HAK8 came out ok - I think it may be a bit too tall - or the top piece not
at the best angle.
btw, some years back I had a guy make a Fig.4 of that patent - it really works to sound nice
Karlson envisioned violins made that way
An externally hosted image should be here but it was not working when we last tested it.
Last edited:
I'd like to see what might be done taller/narrower in K12 bulk vs the original K12 - here's one of my "Pioneer K12" loaded with Beta10cx - a pretty good combo
An externally hosted image should be here but it was not working when we last tested it.
0.55x Scale K15 for Delta 10A
Freddi,
Here is a sim per your request to optimize for a 10 inch Delta 10A with 80 Hz bass extension. It seems that a 0.55x scale K15 with a K-aperture that goes to a cusp should work.
Freq Response:
Cone Displacement:
Impedance:
Impulse Response:
The response above 2kHz may be better in reality as the model is not very good at capturing the effects of the driver cone interaction with the fron cavity. Looks like a super sensitive unit that can be paired with a sub and made in qnty 5 will be great for HT.
Freddi,
Here is a sim per your request to optimize for a 10 inch Delta 10A with 80 Hz bass extension. It seems that a 0.55x scale K15 with a K-aperture that goes to a cusp should work.
Freq Response:
Cone Displacement:
Impedance:
Impulse Response:
The response above 2kHz may be better in reality as the model is not very good at capturing the effects of the driver cone interaction with the fron cavity. Looks like a super sensitive unit that can be paired with a sub and made in qnty 5 will be great for HT.
Attachments
Thank you very much ! - that is a truly small cabinet - fwiw, I think the front shelf should be made to protrude just enough past the port panel as to experiment with its depth - the cabinet is small to fit a 10" - assume 0.55 is based on K15's nominal inside dimensions -- ?
would Beta10cx play in this cabinet?
would Beta10cx play in this cabinet?
Last edited:
the result would be a little bit smaller than the K-coupler below and should work well - it probably would work well with
some fullrange 8s too
some fullrange 8s too
An externally hosted image should be here but it was not working when we last tested it.
Last edited:
I would have to look at the driver magnet size and draw a scale picture to see if it actually fits. It is tight but the bezel is nominally 10in dia and the front baffle is 12+in wide so that should work. One trick is increase the height of the bottom back chamber to clear the magnet and add wood blocks internally to restore the volume gained. I will have to look at Beta10cx but my guess is that it has a substantially higher Qts and probably won't be ideal.
flush mounting vs rear mounting will help a little bit - Delta10A is about 3.75" deep from the frame rear flange to magnet. Magnet diameter with the rubber ring is about 6.375" and without ~6.125". The old model Beta 10cx was about strong enough to work. What would you guess the change if the cabinet's outside dims ended up 21x14x112.5 vs say 20x13.5x11? I have a pair of ancient Beyma 10G200 laying around .
PARAMETRY THIELE - SMALL'A
Częstotliwość rezonansowa, fs
45Hz
Rezystancja cewki, Re 5,8
oma Współcz. dobroci mech., Qms 7,02
Współcz. dobroci elektr., Qes 0,26
Współcz. dobroci całkowitej, Qts 0,251
Objętość zastępcza, Vas 56,1
litra Efektywna pow. membrany, Sd 0,038 m2
Maksymalne wychylenie, Xmax 4,5 mm
Objętość tłoczonego powietrza, Vd 171cm3
Indukcyjność cewki, Le@1kHz
1mH
PARAMETRY THIELE - SMALL'A
Częstotliwość rezonansowa, fs
45Hz
Rezystancja cewki, Re 5,8
oma Współcz. dobroci mech., Qms 7,02
Współcz. dobroci elektr., Qes 0,26
Współcz. dobroci całkowitej, Qts 0,251
Objętość zastępcza, Vas 56,1
litra Efektywna pow. membrany, Sd 0,038 m2
Maksymalne wychylenie, Xmax 4,5 mm
Objętość tłoczonego powietrza, Vd 171cm3
Indukcyjność cewki, Le@1kHz
1mH
Last edited:
good = something else to try. In a regular K12 size I get some ramp-up around 200Hz and the current Beta10cx looks much like Visaton's BG20 from lows to midrange. I don't know how much the cavity shape of the 1956 or so K12 with
10 degree forwards canted port board would compare to a 0.6 scale K15 in the 100-200Hz region - maybe not a lot of difference (?)
a K10 is a nice size as should play with less strain than an 8 - 8 inch is too small to do a lot of work.
btw - L. Cao's F6 in the Karlsonator F6 vs BG12 in a 7-slit "Pioneer/Coral" K12 - this little 6 is quite a speaker for
its price and no whizzer
the standard Karlsonator 6 might be made a bit larger for this L.Cao F6 (?) which dimensions should change?
btw - the pretty 1260W T-QWT helper sub got a graph - thejessman's plate amp only goes to 300
but look how nice its behaved with no graph smoothing applied - he said there's only about 4-6 ounces
polyfil in the first section
the aesthetics of the sub should go well with Karlsons - -two of them and little K/Karlsonator
could make a good system - maybe you could make a foam core version -
the next build will be a little 12klam - Jess Oliver said he and Karlson took a klam out to Yankee stadium
but neither of them were good salesmen - lol
10 degree forwards canted port board would compare to a 0.6 scale K15 in the 100-200Hz region - maybe not a lot of difference (?)
a K10 is a nice size as should play with less strain than an 8 - 8 inch is too small to do a lot of work.
btw - L. Cao's F6 in the Karlsonator F6 vs BG12 in a 7-slit "Pioneer/Coral" K12 - this little 6 is quite a speaker for
its price and no whizzer
the standard Karlsonator 6 might be made a bit larger for this L.Cao F6 (?) which dimensions should change?
btw - the pretty 1260W T-QWT helper sub got a graph - thejessman's plate amp only goes to 300
but look how nice its behaved with no graph smoothing applied - he said there's only about 4-6 ounces
polyfil in the first section
the aesthetics of the sub should go well with Karlsons - -two of them and little K/Karlsonator
could make a good system - maybe you could make a foam core version -
the next build will be a little 12klam - Jess Oliver said he and Karlson took a klam out to Yankee stadium
but neither of them were good salesmen - lol
Last edited:
hey X - what should happen if Delta10A is used in a 0.65 scale K15? would it get near 70Hz? would it lose any punch vs the 0.55 scale example above?
also, I've one new spec B102 which could be used for a small bass guitar cabinet - might have a little K made for it if promising.
Resonant Frequency (fs) 48 Hz
Impedance (Re) 6.89 ohms
Coil Inductance (Le) 0.67mH
Electromagnetic Q (Qes) .42
Mechanical Q (Qms) 5.31
Total Q (Qts) .39
Compliance Equivalent Vol. (Vas) 65 Liters / 2.3cu.ft
Voice Coil Overhang (Xmax) 3.0mm
Surface Area Of Cone (Sd) .03449m2
BL Product (BL) 11.8 T-M
Displacement Volume (Vd) 104 cc
Diaphragm Mass Inc. Airload (Mms) 28 grams
Mechanical Compliance (Cms) .040mm/N
also, I've one new spec B102 which could be used for a small bass guitar cabinet - might have a little K made for it if promising.
Resonant Frequency (fs) 48 Hz
Impedance (Re) 6.89 ohms
Coil Inductance (Le) 0.67mH
Electromagnetic Q (Qes) .42
Mechanical Q (Qms) 5.31
Total Q (Qts) .39
Compliance Equivalent Vol. (Vas) 65 Liters / 2.3cu.ft
Voice Coil Overhang (Xmax) 3.0mm
Surface Area Of Cone (Sd) .03449m2
BL Product (BL) 11.8 T-M
Displacement Volume (Vd) 104 cc
Diaphragm Mass Inc. Airload (Mms) 28 grams
Mechanical Compliance (Cms) .040mm/N
Last edited:
Freddi,
At 0.65x scale you get a little more bass extension with some reduced SPL compared to 0.55x scale case - not a bad performer with 95+ dB sensitivity:
For the BP102, the response seems a little skewed to the bass:
Attachments
thanks so much for your time - - it might not peak on near cutoff depending upon how tuning goes but the loss in spl isn't good. B102 had its magnet size reduced, raising Qt and killing upper mids and treble - but there's enough for bass guitar use - especially considering only 1-10"
for Delta10a, should I build 0.6 scale then tweak rear chamber volume with foam core? How do changes just in front chamber volume affect response when going upwards from 0.55 scale?
in your reply you said "BP102" - was that a typo as Eminence makes a "BP102"?
B102 as a direct radiator - old 59oz magnet version vs new 45oz magnet version
for Delta10a, should I build 0.6 scale then tweak rear chamber volume with foam core? How do changes just in front chamber volume affect response when going upwards from 0.55 scale?
in your reply you said "BP102" - was that a typo as Eminence makes a "BP102"?
B102 as a direct radiator - old 59oz magnet version vs new 45oz magnet version
An externally hosted image should be here but it was not working when we last tested it.
Last edited:
thank you very much for the B102 sim - (that is the later model with qts ~0.39?) - that PRV sim looks phenomenally smooth - do you have K15's shelves in that sim?
is there a good little K for Eminence's Delta8a? I have one in the SK8 but IIRC, was rough on graph
Nominal Diameter8"
Power Handling (RMS)225 Watts
Power Handling (max)450 Watts
Impedance8 ohms
Frequency Response100 to 3,000 Hz
Sensitivity97.8 dB 1W/1m
Voice Coil Diameter2"
Magnet Weight59 oz.
Thiele-Small Parameters
Resonant Frequency (Fs)69 Hz
DC Resistance (Re)5.6 ohms
Voice Coil Inductance (Le)0.82 mH
Mechanical Q (Qms)6.43
Electromagnetic Q (Qes)0.2
Total Q (Qts)0.22
Compliance Equivalent Volume (Vas)0.65 ft.³
Mechanical Compliance of Suspension (Cms)0.35 mm/N
BL Product (BL)14.1 Tm
Diaphragm Mass Inc. Airload (Mms)19.3g
Maximum Linear Excursion (Xmax)3 mm
Surface Area of Cone (Sd)218.2 cm²
green trace is Delta8A in SK8 - other trace is F6 L.Cao in the Karlsonator6 prototype
is there a good little K for Eminence's Delta8a? I have one in the SK8 but IIRC, was rough on graph
Nominal Diameter8"
Power Handling (RMS)225 Watts
Power Handling (max)450 Watts
Impedance8 ohms
Frequency Response100 to 3,000 Hz
Sensitivity97.8 dB 1W/1m
Voice Coil Diameter2"
Magnet Weight59 oz.
Thiele-Small Parameters
Resonant Frequency (Fs)69 Hz
DC Resistance (Re)5.6 ohms
Voice Coil Inductance (Le)0.82 mH
Mechanical Q (Qms)6.43
Electromagnetic Q (Qes)0.2
Total Q (Qts)0.22
Compliance Equivalent Volume (Vas)0.65 ft.³
Mechanical Compliance of Suspension (Cms)0.35 mm/N
BL Product (BL)14.1 Tm
Diaphragm Mass Inc. Airload (Mms)19.3g
Maximum Linear Excursion (Xmax)3 mm
Surface Area of Cone (Sd)218.2 cm²
green trace is Delta8A in SK8 - other trace is F6 L.Cao in the Karlsonator6 prototype
Last edited:
I could try to mount a 10" facing inwards on the front of my SK8 - don't know if it will fit. Its really close in size to what we're discussing
--the wings on the SK8 graph were fast opening which sound nice with my 1772 and 206
the new B102 should make a cool baby bass cabinet in 0.65 and maybe a hair smaller - wonder if 1/2" Baltic birch with some bracing would be stiff
enough to take 150W input without too much flex?
--the wings on the SK8 graph were fast opening which sound nice with my 1772 and 206
the new B102 should make a cool baby bass cabinet in 0.65 and maybe a hair smaller - wonder if 1/2" Baltic birch with some bracing would be stiff
enough to take 150W input without too much flex?
An externally hosted image should be here but it was not working when we last tested it.
Last edited: