Good evening,
does somebody know here where it is the best to place a woofer within a slim & tall cabinet's side panel ? To the bottom like lot of designs have it, or right into the middle, or elsewhere ?
Same question goes for the port: best at the bottom, in the middle or near the top ?
Btw, port: 1 port on the slim back plate or 1 (maybe 2) ports on the side panel above/below the driver ? Or on the opposite side.. ?
Are there any "best" recipes for this topic or doesn't really matter ? Calculation and measurement will be done by WinISD, test made with adjustable port before placing in final ones. I'm interested if there's a simple rules-all setup regarding placement which is said to perform the best (for sound quality).
3-way system. Highs are aligned to mid woofers vertically, with their voice coils. How about time delay behaviour if the woofer is on the side - no alignment with it apparently. (1st XO at 120Hz/24dB 4th order LR for those who are interested).
does somebody know here where it is the best to place a woofer within a slim & tall cabinet's side panel ? To the bottom like lot of designs have it, or right into the middle, or elsewhere ?
Same question goes for the port: best at the bottom, in the middle or near the top ?
Btw, port: 1 port on the slim back plate or 1 (maybe 2) ports on the side panel above/below the driver ? Or on the opposite side.. ?
Are there any "best" recipes for this topic or doesn't really matter ? Calculation and measurement will be done by WinISD, test made with adjustable port before placing in final ones. I'm interested if there's a simple rules-all setup regarding placement which is said to perform the best (for sound quality).
3-way system. Highs are aligned to mid woofers vertically, with their voice coils. How about time delay behaviour if the woofer is on the side - no alignment with it apparently. (1st XO at 120Hz/24dB 4th order LR for those who are interested).
I've asked myself that and did a few experiments with a box before tossing it out. Turns out it does not matter too much OmniDirectional - work in progress
If your LF driver is only used to 120Hz (subwoofer), then its position does not matter too much either. The sound will be omnidirectional regardless.
If your LF driver is only used to 120Hz (subwoofer), then its position does not matter too much either. The sound will be omnidirectional regardless.
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From my experiments I know the closer the port to the woofer the more precise the sound.
Also slot ports sound best if not too narrow ( <= 1 inch ).
Also a radius/taper is beneficial in lowering port noise and improves coupling to the surrounding air.
I would place the port on the same baffle if possible in close proximity.
Proximity also as in "inner end of port to cone distance".
Also slot ports sound best if not too narrow ( <= 1 inch ).
Also a radius/taper is beneficial in lowering port noise and improves coupling to the surrounding air.
I would place the port on the same baffle if possible in close proximity.
Proximity also as in "inner end of port to cone distance".
I like to keep the woofer as close to the next driver up as possible so that i have more latitude in keeping the driver centre-to-centre at less than a ¼ wavelength at the XO.
A couple of our early side firing woofers had them near the floor but flipping them the other way (woofer boxes separate) so they were closer to the midTweeter improved things.
dave
A couple of our early side firing woofers had them near the floor but flipping them the other way (woofer boxes separate) so they were closer to the midTweeter improved things.
dave
Great input, thank you. Driver is a normal bass driver, no sub, but it's a decent big 18" one and well, I just designed a box just as tall as myself for keeping this huge volume non-obtrusive in the living room , f3 at 24hz, I think it will be just fine.
Interesting was to read about port geometry: the shorter the better - seems like... apart from what I also read (1 port: at least 1/3 cone area, 2 ports at least 1/4 cone area). Maybe I'll have to live with 2 ones.. considering. For being as close to the driver as possible I'll try the opposite side first if physical geometry allows it to be there (behind speaker magnet eventually).
Mid and tweeter going into separate box but I cannot flip the bass box, it will be more or less like a tall trapezoid something, keeping parallel walls at minimum (front and back only).
Do you think it affects bass box performance if I put a small "balcony" at the front, at half height ? So the upper volume would be somewhat smaller, still big overall. I'd put the smaller mid-tweeter section above this balcony on separate stands (sticks) so bass resonance doesn't affect mid-high sound that much but they're still almost in place as if they would be built in.
Interesting was to read about port geometry: the shorter the better - seems like... apart from what I also read (1 port: at least 1/3 cone area, 2 ports at least 1/4 cone area). Maybe I'll have to live with 2 ones.. considering. For being as close to the driver as possible I'll try the opposite side first if physical geometry allows it to be there (behind speaker magnet eventually).
Mid and tweeter going into separate box but I cannot flip the bass box, it will be more or less like a tall trapezoid something, keeping parallel walls at minimum (front and back only).
Do you think it affects bass box performance if I put a small "balcony" at the front, at half height ? So the upper volume would be somewhat smaller, still big overall. I'd put the smaller mid-tweeter section above this balcony on separate stands (sticks) so bass resonance doesn't affect mid-high sound that much but they're still almost in place as if they would be built in.
Yes, the shorter the port the better the sound.
1/3 Sd is minimum.
For high xmax woofers more will be better.
One single port will sound better than 2 ports.
2 smaller ones might allow more air velocity before chuffing though.
Given port area is the same.
I got a hard time to imagine said circumstances.
Do you got a picture or drawing?
1/3 Sd is minimum.
For high xmax woofers more will be better.
One single port will sound better than 2 ports.
2 smaller ones might allow more air velocity before chuffing though.
Given port area is the same.
I got a hard time to imagine said circumstances.
Do you got a picture or drawing?
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Seen from the side imagine an "L" shape except that the lower part of the "L" is a very thick line. I'll post a sketch today soon.
Pls forgive me for that quality, I'm not a CAD artist.
I imagined this kind of build (when bass is not side-firing) and I would be insterested if that 90° corner would affect the bass' sound or not. It's actually just space made for the mid-high smaller box to align voice coils vertically to the bass. Crazy and ugly idea, just asking how cabinet shape affects base quality or in this case it wouldn't harm it at all.
sketch
PS: take the tweeter as aligned too, not like here..
I imagined this kind of build (when bass is not side-firing) and I would be insterested if that 90° corner would affect the bass' sound or not. It's actually just space made for the mid-high smaller box to align voice coils vertically to the bass. Crazy and ugly idea, just asking how cabinet shape affects base quality or in this case it wouldn't harm it at all.
sketch
PS: take the tweeter as aligned too, not like here..
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At the frequencies of interest they are so large they will not see the shape, and above that damping should be taking care of it… no real compromises.
dave
dave
Many thanks for your valuable inputs on all topics covered here. Helped a lot. I also hoped at these low-bass frequencies it won't play a big role .. so .. I only have to decide and then try. 🙂
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