I have built 2 sealed dual opposed subwoofer 2x12" with Kappa 12VQ which has 180gr Mms & 16mm Xmax. now i'm going to built 4Way floorstander which will include 2 of Dynaudio 24W100 in sealed 43L, Fb around 65Hz and lpf maybe around 160Hz. built with 8ch dsp & cabinet shape inspired by Avalon.
I'm contemplating between should i go with dual-opposed woofer (front-back or side by side) for cancelation benefit or both woofer on front baffle like regular multiway. considering it's low Mms, not so deep bass, and only 8mm Xmax acceleration might not have too much force. also will it be still good for rear facing woofer up to 160Hz?
Thanks
I'm contemplating between should i go with dual-opposed woofer (front-back or side by side) for cancelation benefit or both woofer on front baffle like regular multiway. considering it's low Mms, not so deep bass, and only 8mm Xmax acceleration might not have too much force. also will it be still good for rear facing woofer up to 160Hz?
Thanks
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Wow. That's quite the setup. Should sound phenomenal. Love esotar drivers. I don't have any answers for you, but I'm looking at doing something similar.
If you do one woofer on front and one one on back, is this rear one wired out of phase to be push/pull? If they are on the same plane, they can both be in phase. I hope you post pictures.
If you do one woofer on front and one one on back, is this rear one wired out of phase to be push/pull? If they are on the same plane, they can both be in phase. I hope you post pictures.
hi I'm planning something similar with somewhat similar drivers . 2x 24w100xl ,15w75,d76af and tweeter 81641. I'm planning dual opposed as its supposed to somewhat cancel vibrations transfered through the cabinet . one thing that just occurred to me is that you might gain some output from the second 24w100 if it was placed under the 1st one because it will be closer to the floor ? I'm thinking of side mounting the larger drivers so that I can have more freedom to chamfer the front panel or maybe curve it as much as possible . do you mind if I ask what your planning to use for dsp/crossover . ?
indeed Esotar is considered holy grail driver in car audio. took sometime and money to collect them. one last upgrade someday maybe from MW160 to Esotar650
yes it should be in phase wired in paralel, so lucky to get this 8 ohm drivers. because for my DOS should be wired in series due to 4ohm paralel will trigger inuke safety
amazing i got builder partner 🙂 this will be upgrade from my previous project 24W100, MW152, Satori TW29RN. i put the woofer close to the floor, i might do the same for back woofer on this build. currently i'm using Zapco Z8 IV
side mount was also my choice, because i'm not good at visual ideas, so beside Avalon i put my attention on this 4 way design which side mount dual woofer. but somehow too slim is not pleasing my eyes, i like big curvy cabinet.
https://taipuuspeakers.fi/en/taipuu-speakers-dsp-active-speakers/
The cabinet seems like it will have enough mass to largely dampen the drivers, so you may not need to go opposed and instead can consider the benefits of placement as mentioned above for SBIR and all that relative to the boundary behind the cabinets.
Very best,
Very best,
You might find this somewhat interesting >
This is to use a 'semi driven' 12 or 15" driver rear mounted. The amazing thing about this is that the most suitable drivers for this are rather cheap
Auto Subwoofers that have very high Xmax & very low Fs. The 'trick to semi drive them' is to connect them via a high value inductor with HIGH DCR.
An inductor in the range of 10 to 12mH would normally be very expensive, however, with a desired DCR of 6 to 10ohms, it is not expensive at all.
This scenario creates what could be called: 'An actively assisted passive radiator', and can create quite amazing results with a touch of room EQ.
PS.
The high DCR of the 'drive inductor' pulls-up the LF impedance way above the 4ohms of the Auto Subwoofer.
The +/- phase wiring is always obvious when you get it right [ the rear 'Sub' and its inductor connect directly to the amplifier ]
The small amount of drive to the 'Car Sub' / passive radiator creates a 'synergy effect' with the very low frequency pressure within the box.
The achieved result is not actually an increase of "BOOM", but rather an increase of very low frequency 'THUNDER' = sub output.
Of coarse, the main front-firing woofer still provides regular bass, and is separately wired WRT the rear device.
The key to success lies in the selection of a VERY LOW Fs 'Car Driver' that roughly matches your desired tuning frequency. EG. 20Hz .
Regarding rear of box 'things', if you want to get adventurous, there is a way to get substantially greater sub-output than a simple rear port >
This is to use a 'semi driven' 12 or 15" driver rear mounted. The amazing thing about this is that the most suitable drivers for this are rather cheap
Auto Subwoofers that have very high Xmax & very low Fs. The 'trick to semi drive them' is to connect them via a high value inductor with HIGH DCR.
An inductor in the range of 10 to 12mH would normally be very expensive, however, with a desired DCR of 6 to 10ohms, it is not expensive at all.
This scenario creates what could be called: 'An actively assisted passive radiator', and can create quite amazing results with a touch of room EQ.
PS.
The high DCR of the 'drive inductor' pulls-up the LF impedance way above the 4ohms of the Auto Subwoofer.
The +/- phase wiring is always obvious when you get it right [ the rear 'Sub' and its inductor connect directly to the amplifier ]
What I described was a form of passive radiator to replace the use of a port. Ports & passive radiators don't have any direct link to electrical damping.
The small amount of drive to the 'Car Sub' / passive radiator creates a 'synergy effect' with the very low frequency pressure within the box.
The achieved result is not actually an increase of "BOOM", but rather an increase of very low frequency 'THUNDER' = sub output.
Of coarse, the main front-firing woofer still provides regular bass, and is separately wired WRT the rear device.
The key to success lies in the selection of a VERY LOW Fs 'Car Driver' that roughly matches your desired tuning frequency. EG. 20Hz .
@Audio>X as i mentioned above, i already have DOS 2x12" sealed subwoofer for L/R channel and plenty of headroom from amplifier never been used because i dont want to annoy my neighbour. my walls are connected to them
I also have future plan to build DOS ported with promising simulation result but it will be refrigerator size.
i prefer to run it without too much tweaking as long as it has enough muscle to do it.
I also have future plan to build DOS ported with promising simulation result but it will be refrigerator size.
i prefer to run it without too much tweaking as long as it has enough muscle to do it.
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Speaker Boundary Interference Response.
Iow the way driver behave wrt the listening space (room)
http://tripp.com.au/sbir.htm
Otherwise dual opposed works like a charm to reduce cabinet born vibration from low dedicated drivers. If sub 200hz xover (since i've experimented with it thanks to Dave's advice about) it's my first design choice. Higher xover and there can be issue depending on cabinet dimension and driver diameter ( directivity behavior related). But with 'large' drivers (12" and bigger) and sub 200hz xover i don't think twice about it.
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this is a brilliant idea never heard of this before so it's sort of sympathetically playing along like an assisted pr
thanks how do you find the mini dsp 2x4hd ? does it provide a reasonable sq . I spose I could start with something like this for testing and upgrade later .amazing i got builder partner 🙂 this will be upgrade from my previous project 24W100, MW152, Satori TW29RN. i put the woofer close to the floor, i might do the same for back woofer on this build. currently i'm using Zapco Z8 IV
side mount was also my choice, because i'm not good at visual ideas, so beside Avalon i put my attention on this 4 way design which side mount dual woofer. but somehow too slim is not pleasing my eyes, i like big curvy cabinet.
https://taipuuspeakers.fi/en/taipuu-speakers-dsp-active-speakers/
ah that's cool I saw your other build how did you find the middome you used in that one I was curious about it as its the only dynaudio dome mid you can still buy ? it seemed suspiciously cheaper than I would have expected
i found last year render with side woofer which also tempting to continue. i think it looks cleaner this way.
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for sure woofer will be cut below 200Hz, i think MW160 should be able for 120Hz or maybe 80Hz but i find Troels 5 way illuminator use SS 18WU cut off is higher 180Hz to give less stress on midbass.
@jccart weird i cant quote your post. i used 2 minidsp 2x4HD, but my stupid action trying to upgrade FW and chose UMIK file and 1 dsp become brick 🤣 i might use 2x4HD later for bookshelf monitor. too lazy to send for service to minidsp HK so i will just use car dsp now for 4 way built.
sound wise minidsp 2x4HD is decent, but many option out there in car audio and i even got 2nd hand Zapco for alot cheaper price. those guys in car audio never stop upgrading their stuff.
Dyn D76AF is still on my local store wishlist and has not been sold, but I dont think it will come to Esotar430 sound quality. still tempted to buy it but i'm trying to reduce unused midrange. Dyn MW152, Alpair 10p, PRV 5MR450 and some FR drivers are laying collecting dust 🙁
sound wise minidsp 2x4HD is decent, but many option out there in car audio and i even got 2nd hand Zapco for alot cheaper price. those guys in car audio never stop upgrading their stuff.
Dyn D76AF is still on my local store wishlist and has not been sold, but I dont think it will come to Esotar430 sound quality. still tempted to buy it but i'm trying to reduce unused midrange. Dyn MW152, Alpair 10p, PRV 5MR450 and some FR drivers are laying collecting dust 🙁
that's interesting I liked the look of the helix car dsps they seemed like good value for what you get .
You should take the chance to connect the magnets mechanically so that the vibration cancels. You have yet and option not mentioned - both bass drivers on the front but one turned with magnet outwards (visible) - this cancels a lot of 2nd.... Se Audio-Pro Ace-Bass.
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