Subwoofer build suggestions wanted

[rick844]

Hey all, I am now ready to replace my 15" ported sub for something a little more compact and I want to veneer it to match my ht cabinet and my anthology towers. 90 percent of my listening is movies and tv, but I do have high demand for quality and low bass during music listening.
I would imagine that a sealed cabinet would help with keeping it smaller, but I dont want to compromise in low frequency if possible. I am open to 15 inch or 18 inch drivers.
I have about 800 watts of mono power to supply, so no plate amp is needed. Room to fill is fairly large at 18' x 30' with 16' ceilings.

Any suggested builds from you experts would be greatly appreciated.

[Bear]

Hey all, I am now ready to replace my 15" ported sub for something a little more compact and I want to veneer it to match my ht cabinet and my anthology towers. 90 percent of my listening is movies and tv, but I do have high demand for quality and low bass during music listening.
I would imagine that a sealed cabinet would help with keeping it smaller, but I dont want to compromise in low frequency if possible. I am open to 15 inch or 18 inch drivers.
I have about 800 watts of mono power to supply, so no plate amp is needed. Room to fill is fairly large at 18' x 30' with 16' ceilings.

Any suggested builds from you experts would be greatly appreciated.

For bass, you want to focus on piston volume (Sd * Stroke). Realistically, if you are looking to go "smaller", I would add "more" to your list. In general, more sources of bass will provide a more uniform loading of the room. So, instead of a single 15", you may want to look at two to four 10 - 12" drivers. Your costs can increase (big, good subs aren't cheap, though!), but in general you will get a more uniform sound that integrates better with your large room.

[rick844]

Thanks, and I had thought of that. But I simply only have room for one sub.

[dar47]

Do you have an attic above or basement crawl space beneath or a spare room adjacent to your room? Best base is an infinite baffle sub!

[Bear]

Thanks, and I had thought of that. But I simply only have room for one sub.

No worries. The SEAS L26 is fairly expensive, but it models well in 14L net (fully stuffed), which is pretty easy to tuck into out of the way places. There are other well-regarded subs that offer a similar compact sealed volume.

[Scottg]

..hmm, small:

Though you already have an amplifier, I'm going to suggest a plate amp (with their coil sensing "servo" design) with a sealed design from Rythmik Audio:

http://www.rythmikaudio.com/DS1204ci.html

[rick844]

Interesting. I live in florida, so no basements unfortunately. The adjacent room my daughters, so unless I want to get hell from her and my wife, that's not an option either. This is the first time I have seen servo design. Is this snake oil, or is it really difference making?

I'll take a look at the seas as well.

[Bear]

Interesting. I live in florida, so no basements unfortunately. The adjacent room my daughters, so unless I want to get hell from her and my wife, that's not an option either. This is the first time I have seen servo design. Is this snake oil, or is it really difference making?

I'll take a look at the seas as well.

Snake oil? No. It's not on the "cable lifter" end of audio. Think of it more like a simplistic way to implement a Linkwitz Transform, but without the math/flexibility -- assuming that your existing plate amp has a good damping factor. In other words, it does provide additional benefits, but there are alternatives that do more/better. Something like a MiniDSP with Dirac Live would give more benefits, but at a larger total spend.

On the disturbing the other occupants front -- that is a function of SPL. With a single driver, you may get cancellations that cause you to turn up the overall volume to cover the nulls. Multiple subs will smooth out the in-room frequency response, especially when using something like a Dirac processor (or even Audyssey SubEQ). You may (there's that word again) then get a more pleasing sound at a lower SPL, which might (have I qualified this enough?) make the other occupants happier.

In my prior HT, I had two sub modules with 2x12" drivers in each (dual-opposed), so I'm a fan. Hurricane Harvey killed those, and I have yet to replace them now that I'm in CA. Prior to that I lived with a 10" Velodyne servo sub, and it was adequate for a small room, but it wouldn't shake the walls like 4x12" could.

[ergo]

I'm planning a build of 2 subwoofers for my Wavecor Ardent pair. As I ideally would like to continue the Wavecor theme as well as the look of the Ardent front panels with beveled/angled cuts I'm leaning towards a closed box design with
SW312WA05-01

Two with each in 45L box is probably more than I need... even one might probably be enough, but as said before spreading the low bass around the room will give flexibility in getting a more even result + match the aesthetics of the Wavecor Ardent setup.





An old picture from Christmas time, but this is the setup they would need to complement. I too have two 500W NCore class-D amps and a MiniDSP 2x4 box for the room mode taming / EQ and Xover. The only problem for now is that the Black cone version is hard to get in Europe. One German distributor will get some in about 4 weeks. So we'll see. I need to get the units first before I start the build.

[rick844]

Another interesting point. When I measured my existing mammoth sub enclosure, the rythmik was almost half as tall and about 6 inches narrower. Based on this, I could theoretically fit two, or two other sub solutions of similar size on the one wall. Lots to think about there for sure. I especially am intrigued by the point made relative to the sound fill of the voids the second sub offers over the one.

[csmielke]

Another smaller option to consider is the CSS SDX10 subwoofer with a pair of PRs Scan Speak 26W/0-00 in a 47.5 liter enclosure. It models solidly into the mid to low 20s with room gain. Jon also modeled this combo a few years ago. You pick the amp to go with it. A pair would be even better but pictures on the wall begin to move with just one.
Chris

[rick844]

Thank you for the suggestion. I would like to stick with larger drivers as I want to be able to produce very low frequencies. I am ignorant and new to this, but I can 10 inch drivers accomplish that? Also, does having more than one driver allow for lower frequencies?

[Horio]

I'm planning a build of 2 subwoofers for my Wavecor Ardent pair. As I ideally would like to continue the Wavecor theme as well as the look of the Ardent front panels with beveled/angled cuts I'm leaning towards a closed box design with
SW312WA05-01

Two with each in 45L box is probably more than I need... even one might probably be enough, but as said before spreading the low bass around the room will give flexibility in getting a more even result + match the aesthetics of the Wavecor Ardent setup.

Ergo, that sounds very intriguing. Make sure you post more on the development of your subwoofer if you decide to move ahead with it. I could see myself being interested in a "matching" subwoofer build for the Wavecor Ardent's down the road.

[CADman_ks]

Thank you for the suggestion. I would like to stick with larger drivers as I want to be able to produce very low frequencies. I am ignorant and new to this, but I can 10 inch drivers accomplish that? Also, does having more than one driver allow for lower frequencies?

Along with you, I'm no expert on any of this stuff, and I rely on the community, or pre-setup designs. I don't have any measuring equipment, so for me, it's all seat-of-the-pants, and does it sound good when I'm done? Definitely not scientific, but it's all I got. Also, my "room" is somewhat similar to yours in size, 20' x 17' x 12' high, and open on one end to a larger space, so in theory, the 20' could be 40'.

I wanted a sub to complement my system, mostly for HT and music, but, like you, I didn't have a lot of space in the room for a huge box, and I had to be aware of the WAF as well, so I was only going to get one box, and even that was under protest.

I settled on this kit:

https://www.parts-express.com/dayton...ndle--300-7092 This is a 12" sub in a 45L sealed box.

I have no idea how low this thing goes frequency wise, but I know this: if you're listening to it loudish, you can feel it in your chest, and loud is maybe even a relative term. I can listen to it that loud, but it's way too loud for my wife. For like home theater stuff, you can feel the bass in action scenes, even at moderate levels. Levels I like to listen to movies at, but maybe not my wife. I've been very pleased with the performance of this box in my setup.

Again, no science, just seat-of-the-pants, but it's another viewpoint, for what it's worth...

[rick844]

Thank you for that suggestion. I was looking at those as well. My friend got the same kit, and it does sound pretty good for the buck. Unfortunately, I want a little more like something like the rythmik. When the suggestion was made i started looking into it. It really seems impressive and is almost half the height of my current sub. I may even be able to fit two of them. Just need to figure out how to build the enclosure myself. Rythmik doesnt seem to give the plans for the front mounted ported option. Still looking into it.

Thanks again.

[csmielke]

Sorry for the late reply to your question. I am no expert but, I did stay at a Holiday Inn Express once. The SDX10 on the original specs had a Qtc of .7 in 24 liters sealed with an F3 of 44z. This pretty much matches the Wavecor example but, with an xmax of 18.4 one way which is I think about 50% greater than the Wavecor driver. The Wavecor has an advantage in size 12" vs. 10". The xbl2 motor at 12.7mm one way (1" peak to peak excursion) has less than 2.5% THD. At the time I bought mine (several years ago) I paid $139 each and about $100 each for the passive radiators so $350 all in vs. around $450 for the single Wavecor. I am very satisfied with how it turned out but, two or more would be even better for the reasons Bear mentioned earlier. My room is not as large as yours and I did not have a need to go lower than the 20s as my focus was music only so, perhaps you need something that can push more air. Lots of trade-offs to consider - compact size vs. large room vs. sub 20hz performance? Good luck with your decision.
Chris

[Scottg]

This is the first time I have seen servo design. Is this snake oil, or is it really difference making?

It is snake oil in the sense that it's not an *accelerometer sensor design, instead it's a current-sensing design. BOTH can dramatically lower stored energy, not simply stored energy relative to the room, but stored energy relative to the driver. This produces a result that's quite a bit more clear, with much better dynamic contrast (..in that the cone isn't droning on with its decay at anywhere near the same rate as a non-servo design).

This design also has some benefits with respect to achieving a flat low freq. response in a small cabinet at a lower voltage requirement than a "boosted"/eq'ed design (..though the plate amp's also have some eq. as well if you want to add more and a very low freq. high-pass filter to limit excursion if desired along with the low-pass filter and phase rotation).

The result is genuinely different, and it's not something you can achieve with dsp eq. (..though that too is likely to be beneficial and can still be added to this).

Also, I believe the driver is rather good with respect to non-linear distortion (without regard to its current-servo operation).


*note: an excellent accelerometer design is even better with regard to vc-position stored energy. Velodyne and better Paradigm subs are good examples.

[CADman_ks]

Thank you for that suggestion. I was looking at those as well. My friend got the same kit, and it does sound pretty good for the buck. Unfortunately, I want a little more like something like the rythmik. ... Still looking into it.

No worries! I understand. You have to get what makes YOU feel like you made the right decision. I make decisions the same way, once I've mulled over all the information I've received.

Good luck in whatever route you decide to go down!

[rick844]

Thanks to all for the wealth of knowledge and suggestions.

[Evil Twin]

Sorry for the late reply to your question. I am no expert but, I did stay at a Holiday Inn Express once. The SDX10 on the original specs had a Qtc of .7 in 24 liters sealed with an F3 of 44z. This pretty much matches the Wavecor example but, with an xmax of 18.4 one way which is I think about 50% greater than the Wavecor driver. The Wavecor has an advantage in size 12" vs. 10". The xbl2 motor at 12.7mm one way (1" peak to peak excursion) has less than 2.5% THD. At the time I bought mine (several years ago) I paid $139 each and about $100 each for the passive radiators so $350 all in vs. around $450 for the single Wavecor. I am very satisfied with how it turned out but, two or more would be even better for the reasons Bear mentioned earlier. My room is not as large as yours and I did not have a need to go lower than the 20s as my focus was music only so, perhaps you need something that can push more air. Lots of trade-offs to consider - compact size vs. large room vs. sub 20hz performance? Good luck with your decision.
Chris

I have obtained and tested the SDX10 also, and find it's performance to be very satisfactory in test systems- no builds as yet, as this is planned for the low end of a full range system using dipole mid bass and an ultra low distortion waveguide top end. The key to this driver's combination is the XLB2 motor, which excels at maintaining a flat BL curve over a long stroke range. The only non-XBL2 motors that approach this are designs with underhung voice coils (quite rare, due to the demands of creating a long conventional gap with high flux excitation) and variable winding pitch designs like the PuriFi 7" woofer.

That system will have an alignment more suited to music, with a QB3 roll off response in a 40L volume, using a 10" RSS265PR. With a small amount of shelving EQ, the response to 25Hz will be very solid, which is generally all that is needed for music.




For HT, response to 20Hz is likely desired, and in this case an EBS alignment in a larger 60L enclosure with 12" PR may be preferred.




But once you are considering 60L and larger enclosures, my attention often focuses on the finesse possible with a wide band, low Q, well designed 4rth order bandpass enclosure using professional drivers, such as this example for the B&C 15SW115, for which the components are waiting in the outer rim for time to build and test... galactic pandemics have a way of delaying many activities and changing priorities.

This design example, one of several I have developed for this driver, has an F3 of 25Hz in 75L, and transient response like a sealed system. In the normal operating range of 23Hz to 125Hz, the impedance and phase present fairly easy loads. Past designs like this, which I've built as long ago as 40 years, have a very well developed sense of pitch provided the cabinet is appropriately stiff.




Being a modern professional driver, the 15SW115 develops a powerful motor using a large neodymium magnetic system. This are available at Parts Express, should you be curious.

[rick844]

I have no idea what you are are talking about. I can only assume you know for sure. Are you suggesting this driver with and enclosure? If so, do you have enclosure plans I can look at? Also, how do you think this would compare to the rythmik?

[Scottg]

Well, the Dark Lord is presenting a few designs here. The first one is a smaller volume (40 liters) to the Rythmik (50 liters) with a low distortion motor (above resonance).

The next is the same design, but with a larger volume (60 liters), and more extension near the average (..look at 20 Hz between the two).

The 3rd is 83 liters with a very different design: instead of the first 2 bass-reflex designs (that use passive radiators), this is what's known as a 4th order bandpass sub (..google should have lots of info. on this). Moreover, it uses a much higher force pro woofer and effectively trades massive excursion (the CSS 10") for higher surface area (15" pro woofer) while having a bit greater efficiency.

I don't think either of the first two will be competitive to the Rythmik (though I could be wrong), but IF you have the room for the 3rd design then it might well be preferred (largely because the sound of efficient drivers with their strong motor force in the driver's gap tend to sound very clear and dynamic). Plus, you wouldn't have to purchase a plate amp (and could just use the amp you already have).

[rick844]

Ahh, thank you Dark lord and Scott. How do I determine the enclosure size for the third design?

[ergo]

Interesting suggestions from outer space comms. The bandpass is a specially interesting brain exercise. 75L + 8L... ok, but one needs to fit a 12cm (4.7 inch) diameter tube that is 91cm (long 35.8 inch) long into that 8L. It is safe to say that in this case the port volume must be deducted from the box volume for sure
Also it would need to be folded few times or perhaps a port formed between the cabinet walls.

[ergo]

Just in case an image from VituixCAD manual to go with above bandpass simulation to illustrate the type of box meant

[rick844]

Ahhh, if I need to have a 36 inch long tube, I'm not sure the enclosure would be smaller than what I currently have. Based on what you are showing, a bass reflex or one with a passive radiator would make it.

[Scottg]

..bandpass passive radiator is a bad idea. :cry:

[rick844]

Yeah, I didnt mean passive with bandpass. I meant passive in the example you gave. Which looks like a sealed enclosure with an active and passive driver.

[Scottg]

..hmm, small:

Though you already have an amplifier, I'm going to suggest a plate amp (with their coil sensing "servo" design) with a sealed design from Rythmik Audio:

http://www.rythmikaudio.com/DS1204ci.html

-no passive radiator/driver.

Sealed 1.8 cubic foot (..51 liters).

[rick844]

Awesome, thank you.

[Evil Twin]

Slot loaded forward port. No tubes required... the area in front of the driver becomes a slot style port, driven from a slot entry on the offer baffle. As I hinted, I have done this in the past... distant past for many of you (70’s)

[Scottg]

..when Imperial Citizens were rocking leisure suits? :P

..I still love certain movie franchises that appeared then, though ironically I don't think of them in context with the '70s, rather Logan's Run. Also, with TV a certain well-"funded" man in a red track suit. ..na,na,na,na,na,na...

[ergo]

Slot loaded forward port. No tubes required... the area in front of the driver becomes a slot style port, driven from a slot entry on the offer baffle. As I hinted, I have done this in the past... distant past for many of you (70’s)

I assumed as much. thanks for confirming. This will still require quite a sizable box but yes the performance promise is also there. For me that design would be too big though.

[rick844]

So, would it be best to go with Scotts recommendation of a sealed woofer from Rythmik or do you have an enclosure design I could look at that would be comparable or better for my application? I would prefer to build and save some coin/get better performance if that is a possibility.

Slot loaded forward port. No tubes required... the area in front of the driver becomes a slot style port, driven from a slot entry on the offer baffle. As I hinted, I have done this in the past... distant past for many of you (70’s)

[Horio]

So, would it be best to go with Scotts recommendation of a sealed woofer from Rythmik or do you have an enclosure design I could look at that would be comparable or better for my application? I would prefer to build and save some coin/get better performance if that is a possibility.

You can buy the driver and plate amp as a kit from Rythmik if you want to save a few bucks and build your own enclosure. I've thought off and on about trying their GR Research driver kit and building my own enclosure.

http://www.rythmikaudio.com/products2.html

They have some down firing plans for the DS1200 and DS1500 drivers here:

http://www.rythmikaudio.com/diy.html

Or if you like their GR Research driver, they have some plans on the GR website here:

http://gr-research.com/servosubkit1.aspx

[Wayne1]

Here is a thread by Danny Ritchie, building the SW-12-04 driver in a sandbox enclosure

https://www.audiocircle.com/index.php?topic=53675

[rick844]

Thank you. I will have a look for sure. Im trying to stick with Sealed as suggested by Stottg and I like the idea of maintaining good low end, and I don't have a giant room in need of ported. Plus the sealed option seems to offer the best music support based on feedback from the experts here and other research I have done over the last few days. I would really like to copy Rythmiks sealed enclosure, but I haven't seen their released plans online. I may ask them for them, but who knows if they would provide. I would like to veneer the sub with the same stuff I have left over from my Anthology build. Of which I am ecstatic with the results btw.

You can buy the driver and plate amp as a kit from Rythmik if you want to save a few bucks and build your own enclosure. I've thought off and on about trying their GR Research driver kit and building my own enclosure.

http://www.rythmikaudio.com/products2.html

They have some down firing plans for the DS1200 and DS1500 drivers here:

http://www.rythmikaudio.com/diy.html

Or if you like their GR Research driver, they have some plans on the GR website here:

http://gr-research.com/servosubkit1.aspx

[rick844]

Wow, putting sand into a sub enclosure was not something I had seen before.

Here is a thread by Danny Ritchie, building the SW-12-04 driver in a sandbox enclosure

https://www.audiocircle.com/index.php?topic=53675

[rick844]

So, I'm leaning towards either buying or building one of two options based on WAF and budget. I don't want to get much north of $1200 and if I can build for less, that would be awesome. I have the tools and skills to build the enclosures, but I need plans. Im not capable of designing my own enclosure. I know Parts Express sells typical 12" and 15" enclosures, but I imagine they may not be of ideal dimensions and size for this. Any suggestions would be appreciated. I love the idea of sealed heart pounding and quality sound, but I also would be disappointed if the LFE in movies was missing. To clarify room measurements 18' wide by 20' deep listening area (with an additional 15' behind which is the kitchen and only a half wall separating the two) with vaulted ceiling peak of 12'.

1. Two Rhythmic L12's
2. One Rythmik F15HP

Thoughts?

[CADman_ks]

So, I'm leaning towards either buying or building one of two options based on WAF and budget. I don't want to get much north of $1200 and if I can build for less, that would be awesome. I have the tools and skills to build the enclosures, but I need plans. Im not capable of designing my own enclosure. I know Parts Express sells typical 12" and 15" enclosures, but I imagine they may not be of ideal dimensions and size for this. Any suggestions would be appreciated. I love the idea of sealed heart pounding and quality sound, but I also would be disappointed if the LFE in movies was missing. To clarify room measurements 18' wide by 20' deep listening area (with an additional 15' behind which is the kitchen and only a half wall separating the two) with vaulted ceiling peak of 12'.

1. Two Rhythmic L12's
2. One Rythmik F15HP

Thoughts?

Check this out:

https://www.parts-express.com/denovo-audio-30-cu-ft-mdf-15-subwoofer-starter-kit--300-7014

This would be the "hard" parts of the cabinet to make. You just cut the outer pieces, and then veneer. From the specs, it appears (needs to be verified) that it would fit the Rythmik 15" sub.

Here is the WHOLE cabinet:

https://www.parts-express.com/denovo-audio-knock-down-mdf-30-cu-ft-subwoofer-cabinet-for-dayton-audio-15-reference-seri--300-7078#lblProductDetails

When I built mine (not a Rythmik), I just used the correct volume, and filled with some fiberglass, and it sounds GREAT, but mine is only a 12" Dayton HO.

Again, I'm no expert on any of this by any means, but I would think that if your goal is to stay under $1200, then go with the one 15". You could easily be under the $1200.

For a 15" you'd need:

http://www.rythmikaudio.com/DS1500ci.html, and one of the above cabinets. Let's say you go with the whole cabinet. That's $200 + $800 for the sub/amp. You're at a $1000.

For 2 12's you'd need:

http://www.rythmikaudio.com/DS1200ci.html (something from this page, there's options), and two cabinets.

Min combo is $650/ea x 2 = $1300
2 cuft Boxes are $150/ea x 2 = $300

You're going to be into the 2X 12's for at least $1600.

While I can't predict what it will sound like in your room, and how heart pounding it will be, I know that my 12" sealed will shake you to the core. I don't know if I could stand much more, but maybe I'm a wimp, too...

When it comes to playing music, this is a good song to see how heart pounding your sub is:

https://www.youtube.com/watch?v=D-h6MoF7HLA

[rick844]

For the single 15", it appears to be close in price, but for the two twelve inch subs, it appears to be more cost effective to just buy finished. Currently the l12s are $559 finished and shipped.

[CADman_ks]

For the single 15", it appears to be close in price, but for the two twelve inch subs, it appears to be more cost effective to just buy finished. Currently the l12s are $559 finished and shipped.

Yeah, I missed that in your last post, that you would buy complete.

I would assume that the complete sub is using a lesser driver and/or amp than the kit I listed, but it's hard to tell from their website.

They do have some good prices on their completed subs for sure...

[dwk]

I have obtained and tested the SDX10 also, and find it's performance to be very satisfactory in test systems- no builds as yet, as this is planned for the low end of a full range system using dipole mid bass and an ultra low distortion waveguide top end. The key to this driver's combination is the XLB2 motor, which excels at maintaining a flat BL curve over a long stroke range. The only non-XBL2 motors that approach this are designs with underhung voice coils (quite rare, due to the demands of creating a long conventional gap with high flux excitation) and variable winding pitch designs like the PuriFi 7" woofer.

For those that have used/tested the SDX10, any sense of how high you can cross if using as a woofer in a 3-way? Would it be acceptable up to 250-300Hz to hand off to a 5" mid?

[rick844]

Are you hijacking my thread? LOL, JK.

For those that have used/tested the SDX10, any sense of how high you can cross if using as a woofer in a 3-way? Would it be acceptable up to 250-300Hz to hand off to a 5" mid?

[rick844]

Agreed, their data is vague. Its also strange that they don't list the plans for their sealed subs. I wonder if there is such little margin that they would loose sales on those. Im going to ask for them anyways.

Yeah, I missed that in your last post, that you would buy complete.

I would assume that the complete sub is using a lesser driver and/or amp than the kit I listed, but it's hard to tell from their website.

They do have some good prices on their completed subs for sure...