Just be warned, if you end up using a MiniDSP, make sure that the amplifier you're planning on driving the subs with has an input sensitivity in the 0.7-0.8 vrms range.
Well buying a miniDSP and playing with it is an excellent start.
It's ready to use, plug in your computer, setup the filters, you're good to go.
Also have a look on Dr. Geddes' studies on multiple subs, he's been using the 3 sealed subs configuration, with proper eq and placement, they will rock!
Building yet another subwoofer, yet another point of source would make sense in the 90s, nowadays the knowledge on this matter is so diffused, also technologies on DSP and measuring with quality are so cheap. Science is your friend and much available.
With a calibrated mic, also available for 60 bucks, you can measure up your system's response, decay, etc, then really plan on improvements, such as acoustic treatment, placement, etc.
Less is more my friend.
cheers
It's ready to use, plug in your computer, setup the filters, you're good to go.
Also have a look on Dr. Geddes' studies on multiple subs, he's been using the 3 sealed subs configuration, with proper eq and placement, they will rock!
Building yet another subwoofer, yet another point of source would make sense in the 90s, nowadays the knowledge on this matter is so diffused, also technologies on DSP and measuring with quality are so cheap. Science is your friend and much available.
With a calibrated mic, also available for 60 bucks, you can measure up your system's response, decay, etc, then really plan on improvements, such as acoustic treatment, placement, etc.
Less is more my friend.
cheers
IMHO, you haven't verbalized what your trying to accomplish with a third sub. I'm sure that the two sealed Ultimax 12 subs you currently have are more than enough(maybe with some EQ tweaking) for listening to any music genre.
If your aiming at trying to get to the lowest octaves and to partially pressurize the room for HT listening why not consider the Ultimax 15 or the consider the Dayton Reference 18 in a downfacing table/end table configuration that's wife friendly.
Either of the above choices will get you those lower octaves and shake the pictures off the walls - just adding a third Ultimax 12 sub in any configuration will not
You could opt for bass shakers in the furniture instead, but again IMHO, I don't like them as they become annoying and distracting very quickly compared to what I proposed above.
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I desire a system that is capable of playing all frequencies loud and clear. HT, music listening and music production. As a previous poster said,, I also want to make some sawdust. Designing and building these speakers give me a tremendous amount of joy and satisfaction. While I do have some money to burn I am also budget minded, if I were to build for an ultimax 15,i would feel that I would want to go from a 500 amp to a thousand watt amp,, which would add costs.
All the subs don't have to cover the same range which is why I also suggested combining what you already have with the Dayton Reference 18 - it will get you down to those lower octaves and because it's about 5db more efficient, sensitivity wise, than your Utimax 12's it will play to the same output level(and more) as your Utimax 12's with just the same 500W plate amps that you are already using.
Maybe removing the drivers and building another boxes?
I see you have followed the orientation from Partsexpress the 2 cu.ft. sealed box.
I'd build two vented enclosures, this Bash 500w should be enough to drive the Ultimax 12, coils wired in series (6,6 ohms) so pushing them at 300w, giving 108,5 dB.
Something like the image attached, there's a little boost 2,5dB at the end I know, I've been using mine like this with a 3dB boost, but I don't use the sub on the corner. According to Geddes middle-sideways gives a good excitation for the room.
cheers
I see you have followed the orientation from Partsexpress the 2 cu.ft. sealed box.
I'd build two vented enclosures, this Bash 500w should be enough to drive the Ultimax 12, coils wired in series (6,6 ohms) so pushing them at 300w, giving 108,5 dB.
Something like the image attached, there's a little boost 2,5dB at the end I know, I've been using mine like this with a 3dB boost, but I don't use the sub on the corner. According to Geddes middle-sideways gives a good excitation for the room.
cheers
Attachments
Thanks for all of the input so far. My stubborn self is going to proceed with building a 3rd sub. The building is as enjoyable to me as the final product. I'm only a couple of years into this hobby and as I go I will branch out and try the different things recommended to me. i will build a 15" vented sub this time around. I'm already looking at the dayton reference hf and another bash amp. At this point in my hobby I enjoy the ease of a plate amp. I thought about re building the current sealed boxes but I really do like the "punch" that they provide.
The most important is to have the correct alignment. Make the box a little to small or big and it doesn't perform. Each driver has it's own limitations, also for EQ if you're going to use it. Is not the driver you are looking at that's your priority, but the space/volume (net) you have available is the question. Then go choose the driver that performs best in such enclosure parameters, net, Q, F3, SPL (and all) you look for. When you say you look at a 15", I wonder (read other members).
- What's your available net volume (footprint/space). You mention room, which is 20X15. footprint could be 30-36 inches deep or wide and up to ceiling on your post #8.
- A 36"x30"x70" gives a 1240L/43.790ft³, 1084L/38.281ft³ (net) with 2.2cm ply.
- That will give you almost all the enclosure dimensions under the ~1000L/35ft³ mark. If smaller than () say so now or you will be far away in your calculations...
- Are you looking for an important or specific SPL/sensitivity or roll-off/LF extension besides the specs you already mentioned before. There are drivers with more output but less extension. Drivers that bjorno modeled (your drivers) on his post (#12) do the ~16Hz/F3 mark.
- Do you go with the sealed option or different; BR, other.
If you are going for it with that 15" HF driver, here is what one of my friends did with the same driver in a ported enclosure.
Working interior space after all braces and driver account for = 7 cu ft.
all 3/4" MDF with double thick front baffle
4" flared(both ends) port 16" long
Box tuned to 17 Hz
HF driver xmax will be reached at 300W
Output = 112 db
f3 = 21 Hz
f10 = 14Hz
And yes, it is clean for music but does shake your socks with LFE from movies
Working interior space after all braces and driver account for = 7 cu ft.
all 3/4" MDF with double thick front baffle
4" flared(both ends) port 16" long
Box tuned to 17 Hz
HF driver xmax will be reached at 300W
Output = 112 db
f3 = 21 Hz
f10 = 14Hz
And yes, it is clean for music but does shake your socks with LFE from movies
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I went for it. I built a third subwoofer using the dayton reference HF 15". very large enclosure,,ended up being 8.4 cubic feet after bracing. 2 4inch 16inch long ports,,. bash 500 amp. bassbox has the f3 at 22Htz. I am completely satisfied with my decision to build. The fullness of the lower frequencies that this sub provides has made my system complete. Movies are incredible! Music is wonderful. I worried that the 15 would drown out the 12's, but it does not. I can hear the tightness of the 2 12's just as clear as I can hear the rumble of the 15. I am thinking of minidsp still,,,or possible putting a 50 hertz highpass on the 2 12's. I appreciate everyone's advice. I am stubborn and hard headed,,but I do learn from you guys despite my stubborness. I feel a bit sad that I have no more speakers to build. I may have to sell it all and start over. For now I will just enjoy.
probably need a new receiver,,I believe my Denon-AVR 3805 is possessed by the devil,,,,sometimes turns on by itself,,occasional pops, or clicks to random speakers,,,
probably need a new receiver,,I believe my Denon-AVR 3805 is possessed by the devil,,,,sometimes turns on by itself,,occasional pops, or clicks to random speakers,,,
Hah! Might be time for a new one anyway, with HDMI switching and support for BD formats.
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