Well, here is where I quote GM's tagline: Loud is Beautiful if it's Clean!
I aim to be clean - that is, low HD. What do you consider as a "clean" level of HD for your subs?
The width and depth control the volume and making it 1.09x scale in both width and depth gives you about the 0.5m x 0.5m constraint. Scaling height to 2.6x seems to give best tradeoff between efficiency and extension.
Here are sim results with 17 Hz HPF and 85 Hz LPF (-24dB/oct BW).
SPL vs freq at 2.83V:
SPL vs freq at xmax (20 volts rms):
Not the most efficient sub woofers but might just work for you - but 110 dB may just be enough for you to rattle some picture frames and wondows on the Landlord's house?
Attachments
The one DeonC suggested from post 90. A GR something or another.
http://www.diyaudio.com/forums/subwoofers/254948-moak-mother-all-karlsonators-aka-magnificent-monster-9.html#post3922608
It's this one:
Rythmik Audio GR Research GR SW-12-04 driver
from the:
Rythmik Audio GR Custom Install 12" Direct Servo subwoofer
It is a driver intended to be used with the Rythmik Audio servo amplifiers, and in that configuration it gives some of the lowest distortion bass available. You have an option to use two drivers with an amp and I think in the MOAK that will lead to some of the best bass available anywhere.
Of course you could always go for their dual DS1500 CI 15" subwoofers if dual 12" subs aren't enough to destroy your house.
It uses this driver: Rythmik Audio DS1501 15" subwoofer driverHere are the specs:
Model DS1501
fs 17.5Hz
BL 15.8
VAS 295L
Qms 3.737
Qes 0.344
Qts 0.315
Sd 809 cm2
Re 3.00 ohms
Le 2.5 mH
Driver cutout 14-1/16"
Diameter (outer) 15-5/16"
Driver depth 6.75"
Driver basket lip depth 3/8"
Magnet depth 1.68" (0.84" dual stack)
Power handling 500W RMS
xrk971, are you interested in doing a sim with a pair of these per side. No limits on size. Now that would be the real MOAK!
Deon
PS. Here are a couple of YouTube vids to whet your appetite (and these are all in small cabs):
Rythmik FV15HP Direct Servo subwoofer 15" ported audiophile sub
Rythmik Fv-15 HP sweep
And go to this channel for a few vids:
24852235's videos
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Correct, but the cabinet size was limited to fit my available space (and the landlord's patience). They might do better in bigger cabs.
Freddi,
That box looks real nice and Jessman did another bang up job on the woodworking. Did you ever post the design or drawings for this speaker - maybe in the other thread? That Infinity driver is a real bargain for $60 though. Can't wait to hear your listening impressions. Shipping this box from Washington State to WV might be a little challenging? Looks fantastic.
That box looks real nice and Jessman did another bang up job on the woodworking. Did you ever post the design or drawings for this speaker - maybe in the other thread? That Infinity driver is a real bargain for $60 though. Can't wait to hear your listening impressions. Shipping this box from Washington State to WV might be a little challenging? Looks fantastic.
While those are beautiful speakers, and can likely be used to vaporize small children at a distance of 50 feet at full power, I was particularly taken with all the response graphs.
While these are for actual units, is there a modelling package (Excel macros would be great) that allows one to simulate different drivers in a standard 12" Karlson? I have a pair of the originals, built from a kit in 1958, and given to me by the original owner.
They came with some beautiful Lafayette coax drivers made by Goodmans. I stained the cabs a red mahogany and finished with poly. Look beautiful, except where the wood filler--filling in the nicks at the edges of the plywood, likely because the Karlson factory didn't use a sharp sawblade--didn't take the stain. (Grrrr! It said it was stainable on the package...)
Some PMs with Freddi convinced me that I could, in fact, use these as subwoofers for my home theater setup, albeit with new drivers. I, of course, can't abuse the Goodmans this way, and besides, actual subwoofer drivers built for the purpose, or some 12" standard woofers with a low frequency response, would likely sound better. I don't need huge power, since my living room is small. 20W would probably liquify my organs.
Anyway, I looked around for modelling software, but couldn't find it. What should be I searching for? Something like Jeff Bagby's cabinet modeler, except for Karlsons, would be perfect.
While these are for actual units, is there a modelling package (Excel macros would be great) that allows one to simulate different drivers in a standard 12" Karlson? I have a pair of the originals, built from a kit in 1958, and given to me by the original owner.
They came with some beautiful Lafayette coax drivers made by Goodmans. I stained the cabs a red mahogany and finished with poly. Look beautiful, except where the wood filler--filling in the nicks at the edges of the plywood, likely because the Karlson factory didn't use a sharp sawblade--didn't take the stain. (Grrrr! It said it was stainable on the package...)
Some PMs with Freddi convinced me that I could, in fact, use these as subwoofers for my home theater setup, albeit with new drivers. I, of course, can't abuse the Goodmans this way, and besides, actual subwoofer drivers built for the purpose, or some 12" standard woofers with a low frequency response, would likely sound better. I don't need huge power, since my living room is small. 20W would probably liquify my organs.
Anyway, I looked around for modelling software, but couldn't find it. What should be I searching for? Something like Jeff Bagby's cabinet modeler, except for Karlsons, would be perfect.
Retrovert,
I have a model of the Karlson in AkAbak and can run sims for you if you post driver TS params and tell me which size Karlson or Karlsonator you are using. I am not aware of any Excel spreadsheet that can do this.
Software packages that can be used also include 3d FEA solvers like ABEC3 and Comsol Multiphysics. My AkAbak scripts are approximate models as they are 1d lumped element.
I have a model of the Karlson in AkAbak and can run sims for you if you post driver TS params and tell me which size Karlson or Karlsonator you are using. I am not aware of any Excel spreadsheet that can do this.
Software packages that can be used also include 3d FEA solvers like ABEC3 and Comsol Multiphysics. My AkAbak scripts are approximate models as they are 1d lumped element.
Thanks for the suggestion and offer, xrk971. Very kind of you to offer, and I may need to take you up on that. Those fancier packages look very complicated compared to what I'm used to in terms of "type in some Thiele-Small parameters and watch the magic instantaneously happen on screen" interface.
Now that I know what to look for, I found your model writeup here:
http://www.diyaudio.com/forums/full-range/213594-karlson-10.html#post3528706
Assuming I can figure out how to install the software, are there script savailable somewhere that specify the Karlsons so I don't need to pester you as I change the drivers?
I have a pair of older woofers that go down to 25Hz for which I need to generate the T-S parameters. Also have a spare pair of Bozak woofers which go down to 40Hz. Not as impressive as a dedicated subwoofer, but should be low enough for home theater?
Now that I know what to look for, I found your model writeup here:
http://www.diyaudio.com/forums/full-range/213594-karlson-10.html#post3528706
Assuming I can figure out how to install the software, are there script savailable somewhere that specify the Karlsons so I don't need to pester you as I change the drivers?
I have a pair of older woofers that go down to 25Hz for which I need to generate the T-S parameters. Also have a spare pair of Bozak woofers which go down to 40Hz. Not as impressive as a dedicated subwoofer, but should be low enough for home theater?
Retrovert,
The only Akabak scripts for Karlson as far as I know are the ones I developed myself. I have given enough clues that someone who knows how to model systems with Akabak should be able to figure out. However, I am not releasing the scripts publicly as they represent a good deal of work and IP that I put into them. I don't mind running sims for you though.
Regards,
X
The only Akabak scripts for Karlson as far as I know are the ones I developed myself. I have given enough clues that someone who knows how to model systems with Akabak should be able to figure out. However, I am not releasing the scripts publicly as they represent a good deal of work and IP that I put into them. I don't mind running sims for you though.
Regards,
X
I think IG81 approximated the K15 in Hornresp - posted somewhere in Karlson thread I think. I can also post a basic 3 chamber bandpass box with semi tapped horn output that will get you 90% of the sim of a Karlson sans effect of K aperture which determines the final bass roll off slope and extension.
Having never used Akabak, I didn't realize it was difficult to specify a speaker. Sorry about that. Wasn't trying to get any IP. Didn't even think about that. I've only used the Bagby calculator which was trivial enough, and I saved the parameters in a file so I could send them to people. I will you a PM with the parameters for two of the speakers. Thanks again!
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