Hi xrk971,
Post #198: "...making both the front and rear/lower chambers one big one rather than two separate ones."
I have been playing around w/ that idea, but don't have a presentable drawing yet. The "bad" thing is, that you'll end up w/ a standard bass-reflex PPSL real quickly. 🙂
I'll draw some more on this general idea. Probably around the size I intend to use for my sub/stands.
Regards,
Post #198: "...making both the front and rear/lower chambers one big one rather than two separate ones."
I have been playing around w/ that idea, but don't have a presentable drawing yet. The "bad" thing is, that you'll end up w/ a standard bass-reflex PPSL real quickly. 🙂
I'll draw some more on this general idea. Probably around the size I intend to use for my sub/stands.
Regards,
But the vent still comes out the slot and not separately so it will still be a 6th order band pass.
Hi xrk971,
Post #202: "But the vent still comes out the slot and not separately so it will still be a 6th order band pass."
Here are some doodles, starting w/ what my current plan looks like, then using an internal duct from the plenum to a combined chamber, then a BR w/ a PVC duct, and finally a BR w/ a slot duct.
By the way, have you had time to look @ the MCM 55-2421 in a Karlson sub yet?
Regards,
Post #202: "But the vent still comes out the slot and not separately so it will still be a 6th order band pass."
Here are some doodles, starting w/ what my current plan looks like, then using an internal duct from the plenum to a combined chamber, then a BR w/ a PVC duct, and finally a BR w/ a slot duct.
By the way, have you had time to look @ the MCM 55-2421 in a Karlson sub yet?
Regards,
Yes, and it doesn't look good. The Karlsonator wants a moderate Qts driver. With low Qts, the mass loading of this design doesn't make much bass. It may work better in a K15 proper.
Hi X,
Thanks for the additional information on using the 55-2421 in a Karlsonator. I was not proposing, just asking. It's easy to pop blocks from one drawing into another, that's why the Vifas and the MCM.
Regards,
Thanks for the additional information on using the 55-2421 in a Karlsonator. I was not proposing, just asking. It's easy to pop blocks from one drawing into another, that's why the Vifas and the MCM.
Regards,
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Hi Tb46
I forgot to ask you which is best to round off your measurement to 1/8 or 1/16.
I am on my way to go cut some plywood.
I forgot to ask you which is best to round off your measurement to 1/8 or 1/16.
I am on my way to go cut some plywood.
Hi lawbiding,
Gee, I always use 1/64th (or 0.1mm) - but I realize that's a bit anal. Even 1/16" gaps are way to large.
Regards,
Gee, I always use 1/64th (or 0.1mm) - but I realize that's a bit anal. Even 1/16" gaps are way to large.
Regards,
This Little box little box is more complex to construct compare to the 212d2 PP design, but I am Loving it. I should have some pictures today or tomorrow.
Awesome news! You work really fast and we are all looking forward to seeing the result of the fruits of your efforts. I think this may qualify as a unique alignment due to the asymmetry - I certainly have not seen another speaker with displacement predictions that look like this. I am curious to hear how it sounds flipped around with vent at the top and having a top speaker placed on it.
For those who may have lost the bead on this rapidly evolving project, here is what it will look like courtesy Tb46.
For those who may have lost the bead on this rapidly evolving project, here is what it will look like courtesy Tb46.
As long as the 2 volumes are the same, I think the results will be good! Is the speaker basket volume factored in?
Hi BP1Fanatic,
Post #215: "...Is the speaker basket volume factored in?"
Yes, when making the drawing I got the gross volumes as 127.056in^2 and 116.484in^2, and calculated the net volumes as 120.533in^2 and 120.492in^2; with the difference being 0.040in^2. This includes the subtraction of loudspeaker contribution in the left/upper chamber, and the addition of cone/hole volume in the right hand/lower chamber.
Regards,
Post #215: "...Is the speaker basket volume factored in?"
Yes, when making the drawing I got the gross volumes as 127.056in^2 and 116.484in^2, and calculated the net volumes as 120.533in^2 and 120.492in^2; with the difference being 0.040in^2. This includes the subtraction of loudspeaker contribution in the left/upper chamber, and the addition of cone/hole volume in the right hand/lower chamber.
Regards,
Hi BP1Fanatic,
Post #216: "...Volumes as...in^2..."
This was meant to say that I calculated the gross volumes from the gross cross-sectional areas and the enclosure internal width, and then subtracted/added the respective driver contributions, and re-calculated the net volumes and areas. (Is this any clearer?) Obviously, the volumes are not in in^2.
Regards,
Post #216: "...Volumes as...in^2..."
This was meant to say that I calculated the gross volumes from the gross cross-sectional areas and the enclosure internal width, and then subtracted/added the respective driver contributions, and re-calculated the net volumes and areas. (Is this any clearer?) Obviously, the volumes are not in in^2.
Regards,
Am back
Hi
I hope you guys didn't count me out. I had a little cold for the pass few days so i stay in and play with my new toys Minidsp and Jbl 124d.I am feeling a little better so I make some saw.This minidsp is wicked I love it.
Hi
I hope you guys didn't count me out. I had a little cold for the pass few days so i stay in and play with my new toys Minidsp and Jbl 124d.I am feeling a little better so I make some saw.This minidsp is wicked I love it.
Lawbiding,
Good to hear from you - wondering what happened to you because you are normally very fast. Hope you feel better soon. Nice work and great progress - thanks for sharing. Don't forget to add bracing to the inside of the big chambers. Add some holey brace panels to break up the longitudinal standing waves in the back chamber.
I love my miniDSP too, I just got a second one. I see you have the balanced input ones - do you have pro gear to drive it?
Good to hear from you - wondering what happened to you because you are normally very fast. Hope you feel better soon. Nice work and great progress - thanks for sharing. Don't forget to add bracing to the inside of the big chambers. Add some holey brace panels to break up the longitudinal standing waves in the back chamber.
I love my miniDSP too, I just got a second one. I see you have the balanced input ones - do you have pro gear to drive it?