Perceval, it does look like your dimensions are not 100% correct - both the aperture and the aspect ratio of the box.
Your photo is not very hires, but there is something else that does look suspect and it seems there is some glue between the aperture and the driver baffle? Could be the photo, but it does look strange. I highlighted the area on the attached photo. Could you post a photo without the aperture? And how does it sound without the aperture?
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I did not line the top / back wall of the enclosure, besides right behind the driver.
I put felt, as X mentioned, behind the aperture wings, at the height of the driver.
The aperture is locked in place with a foam gasket between the outside edge of the aperture and the enclosure, then screwed in place.
Inner box dimensions are exactly as the diagram mentioned: 300mm tall x 165mm deep x 165mm wide.
I also followed dimensions for the aperture. Maybe the outside dimensions appear much bigger because by using the 15mm plywood, it added 30mm all around
That is a little felt lining peeking out because of the angle of the shot.
Then all seems ok. Just trying to debug here. You should fall off your chair when you first hear this speaker. Not sure why yours is not behaving so well?
I suspect it is the wood vs foam core effect here. Hmm....
Most people love this speaker and the 3 cases where they weren't impressed have all been wood builds.
I might add a warning on Post 1 that this speaker is best made with foam core for best sound. One easy compromise is to make a foam core cabinet but thin plywood and foam core aperture. That still sounds good.
Most people love this speaker and the 3 cases where they weren't impressed have all been wood builds.
I might add a warning on Post 1 that this speaker is best made with foam core for best sound. One easy compromise is to make a foam core cabinet but thin plywood and foam core aperture. That still sounds good.
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I wonder if you don't perhaps have too much stuffing? Here is a photo of mine. I only lined the sections behind the driver with thin black felt (2mm) - only bottom and back, not against the sides. Then some cotton wool in the upper section of the "whatever you call that section behind the driver baffle". Then very light pillow stuffing in the bottom half of that whatever section. I have nothing at the back of the apertures. Hope it helps.
PS: If you use wood you might need even less stuffing or lining?
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twocents- My stuffing routine is similar to yours except I also stuff the chamber where the driver is and a small amount at the bottom of the rear. Some also use open cell foam where your black felt is. I've tried that as well.
Both pair of my MK0.41X sound excellent. Compared to OB designs (which I dabbled with 10 years ago) it may seem a bit boxy in the low mids. I added a second layer of foamcore for the K lens and weigh down the box with ceramic tiles to tighten up those frequencies. They also may be lacking a bit in the highs. I am old enough to not hear much above 14kHz. To me the sound is smooth and non-fatiguing.
Both pair of my MK0.41X sound excellent. Compared to OB designs (which I dabbled with 10 years ago) it may seem a bit boxy in the low mids. I added a second layer of foamcore for the K lens and weigh down the box with ceramic tiles to tighten up those frequencies. They also may be lacking a bit in the highs. I am old enough to not hear much above 14kHz. To me the sound is smooth and non-fatiguing.
Hi Perceval,
If it would not be too much trouble, could you please build a quick and dirty foam core 0.40x Karlsonator and re-evaluate with TC9FD? I would love to get to the bottom of this sound quality discrepancy that I seem to be seeing a trend with folks who build all-wood implementations. Since you did the hard work of making an all wood one already, you are a natural for trying the foam core. I will give you some incentive to do this, please see PM
Cheers,
X
won't be available until Dec 22. I like silk domes but wish they had put a 3/4" one on it. Costs more than a W5-2143. Hmmm.
That's right. My brain is sometimes feeble. I'm afraid wooden boxes are beyond me these days. How does the double foamcore baffle do at supporting the 2143? it seems a heavier driver than what I've used.
Is there a drawing for the XKi w/2143? I've seen ur specs in that thread, but they are 2.5" deeper overall than the drawing for the PA130, and the gap vent is only .25 inch different so I'm unclear on the angle of the baffle and piece above it and where the vent is placed exactly.
Is there a drawing for the XKi w/2143? I've seen ur specs in that thread, but they are 2.5" deeper overall than the drawing for the PA130, and the gap vent is only .25 inch different so I'm unclear on the angle of the baffle and piece above it and where the vent is placed exactly.
No drawing yet but very straightforward. Make box 12in tall x 10in deep x 8in wide all internal dimensions. Make vent 0.5in deep x 8in wide (naturally) x 5.75in long at top. Give it about 1in breathing room to exit into front chamber. Make front chamber by angling the board holding driver such that the vertex is about 3.75in to 4in deep from front of box. Make the board that holds the bezel of drier big enough to support it and to fit magnet when tilted back without having driver magnet bump bottom panel. I use triple ply corrugated cardboard glued to foam core front to support driver. I added blocks of triple ply cardboard to where screws go for good thread purchase by drywall screws. K aperture is rather wide to allow HF to escape make aperture intersect with driver surround when viewed from front. Line front chamber with foam or felt. Line aperture with felt. Make aperture from sandwich of foamcore-triple ply cardboard-foamcore bonded together with liquid nails (non VOC) or similar construction adhesive. Line rear chamber with felt or foam as usual and add a moderate wad of fiberglass or polyfill in main chamber behind driver.