Hi. My 10 years old China Fr drivers which I like a lot ,it's rubbers worn out(last picture )and I bought different but similar drivers 8 ohm instead of 4 ohms. I will use them for my Fast setup. I think I will make 2. Order pllxo and XO frequency will be around 170hz.
I used BBC ratios for inside dimensions of box. And box sheets will be like first picture.
FS:72hz
Qts:0.57
Vas:4.8lt
İnside dimensions will be 203x165x132mm and box volume about 4.4liters( with effective of poly fiber fill it will be about 5.5 liters)
I think this design will be very good. I already have about 2 meters sheets of 203mm.So it will be easier for me.
What about diffraction of the speakers? Is there a benefit if I round with a milling cutter the left and right sides?( Instead of sharp edges.I know sphere is best for preventing diffraction but Wife started using my IKEA bowls which I bought for my projects and doesn't want to give them to me😂) Best regards
I used BBC ratios for inside dimensions of box. And box sheets will be like first picture.
FS:72hz
Qts:0.57
Vas:4.8lt
İnside dimensions will be 203x165x132mm and box volume about 4.4liters( with effective of poly fiber fill it will be about 5.5 liters)
I think this design will be very good. I already have about 2 meters sheets of 203mm.So it will be easier for me.
What about diffraction of the speakers? Is there a benefit if I round with a milling cutter the left and right sides?( Instead of sharp edges.I know sphere is best for preventing diffraction but Wife started using my IKEA bowls which I bought for my projects and doesn't want to give them to me😂) Best regards
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Hi. Sorry this shape is not good for Waf and i only want to build sealed design . Thank you and best regards
Greets!
Re corner radii; they're mostly cosmetic until quite large, i.e. 2.03 cm thick panel = 34400/2/pi/2.03 = ~2697 Hz, so your call as to whether it's worth it from an acoustical POV.
Re corner radii; they're mostly cosmetic until quite large, i.e. 2.03 cm thick panel = 34400/2/pi/2.03 = ~2697 Hz, so your call as to whether it's worth it from an acoustical POV.
You're welcome!
In theory and IIRC it will roll off -6 dB around ~2.7 kHz, which in turn will somewhat smooth out the BW above this point in the horizontal plane, so recommend doing it in the vertical plane also and ideally push these lower in frequency if you have the tool(s) to make a larger round-over.............
In theory and IIRC it will roll off -6 dB around ~2.7 kHz, which in turn will somewhat smooth out the BW above this point in the horizontal plane, so recommend doing it in the vertical plane also and ideally push these lower in frequency if you have the tool(s) to make a larger round-over.............
I bought a pair of these on a whim ages ago and finally built the sealed enclosures one morning - well-damped 1l stainless steel cylindrical biscuit tins filled with long hair wool with the drivers held in place on one end with RTV silicone.
I demoed them to an audiophile friend a few days later, who listened intently to them (hidden behind and old piece of parachute fabric) playing various of his favourite test tracks. He finally looked at me and said: "They're a bit light on bass aren't they - have you finally bought those Quad electrostatics you've been promising yourself?". No word of a lie...
I demoed them to an audiophile friend a few days later, who listened intently to them (hidden behind and old piece of parachute fabric) playing various of his favourite test tracks. He finally looked at me and said: "They're a bit light on bass aren't they - have you finally bought those Quad electrostatics you've been promising yourself?". No word of a lie...
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Because of I am obsessive person I want to build best enclosure as possible. I decided to build egg shape to prevent modal resonance ( I read sphere may cause it), chatgpt draw me how to make it. I do not know if anyone build a plywood egg shape sealed enclosure.
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Riht, don't want sphere as it has a theoretically infinite number of the same eigenmode(s).
Better, but still a highly resonant design. For truly random decay cabs one needs to use a 3D room calculator
Yes but imho stuffing will help a lot and reduce resonances right? And also adds extra virtual volume. I am building sealed so maybe it is not big problem
that may very well be true Greg, but can anybody really hear it. These are from back in the day, but they've got attributes that I've never improved on.
http://www.vitalstates.org/diy/spheres/vsl-spheres.htm
Sphere is amazing if properly tuned (double cavity inside for resonance). But they are complicated to build and take more space so are not common. Elipson did a lot in the past but customers were pro audio. A lot in fullrange. All ported i think. In china you can buy a lot of Transmission Line enclosure for 4 inch drivers using CNC for pretty cheap if you can talk in chinese. I made one for this kind of fullrange. Not perfect but pretty good already.
True, didn't mean to imply otherwise, just depends on whether you want to only damp its resonances minimal damping or stuff enough to get the extra 'volume' (attached).
AFAIK, all the links to this doc has gone the way of the Dodo Bird, so hope someone/several? will add it with a link to their website(s).
Teardrop. A la Hershey's Kiss, or a kind-of heart shape rotated about its central axis.
The mounting depth can vary: sunken in for a wave-guide effect, or flush.
The 'point' at the rear is intended to guide the diffracting sound waves backwards, so they don't converge onto themselves as with a sphere. To determine an 'optimal' shape would probably require simulation and testing, but I think some very nice approximate shapes could be made by hand.
As for building... How good are your artistic skills?
The mounting depth can vary: sunken in for a wave-guide effect, or flush.
The 'point' at the rear is intended to guide the diffracting sound waves backwards, so they don't converge onto themselves as with a sphere. To determine an 'optimal' shape would probably require simulation and testing, but I think some very nice approximate shapes could be made by hand.
As for building... How good are your artistic skills?
They can by its frequency response between stuffed and lightly damped, i.e. my 'knee jerk' response was strictly for its interior as shown, not WRT its outer shape as Harry Olson proved.
I would be curious to try this famous Harry Olson thing to see how with closed eyes I can hear it (outside of looking at curves)