dgage

Hadn’t seen this before but I don’t often go to the main website. But with my (latest) iPad Pro 12.9, the sides of the website are cut off. I can scroll to the right but the left is cut off with no way to read the very left text. Untitled.pdf

I agree, I think of 12s or even 15s as midbasses for home theater rooms. It takes roughly 2 sealed 12s to equal the output of a single sealed 15. 2 15s to equal the output of a single 18. 2 18s to equal the output of a 24. So a single 24 has more and deeper output than 8 12s.

I have run the SP amps at 1 ohm before and I noticed no loss of power with 2 subs driven off the same amp at 1ohm and 2 separate subs driven off 2 separate amps. However, I don’t have measurements but there definitely weren’t any noticeable drops. I’m sure the power is reduced somewhat but for the savings, it could be a good solution or at least a good stopgap until a second amp could be purchased but you might find it is not needed depending on how hard you plan to push the sub/amp.

I think studios should standardize on the Mariana 24 just so they wouldn’t miss those sorts of issues but I might be biased.

And then there’s the Lone Survivor movie where there is a 6.7 Hz signal (helicopter rotor artifact) that is 10 dB louder than the rest of the soundtrack. Put a hurting on my 24s when we were pushing them at a GTG (GeTogether). Really wish sound engineers checked their work before mastering millions of movie discs.

Correct, we just glue with PL Premium 3X and then clamp for 24 hours. Wood glues, when used correctly, are stronger than the actual wood. I’ve tested this by gluing two parts together at a right-angle and then swinging the wood against a tree, the wood broke but the joint did not. We tested the 8X and did not like it as much though I think cost had a lot to do with it since we have to worry about cost in a production instance that DIYers don’t have to worry about. But I’m willing to pay more for better performance, but we liked the PL 3X better. Here is a video showing the construction of our Mariana 18S subwoofer. We put it together and use 2 ratchet straps to go around the sides and then 8 parallel clamps for front to back. Like I said, we let the glue dry for 24 hours and the enclosure is solid. The corners are 2” mdf corners, everything else is 18mm Baltic Birch plywood.

I use PL Premium 3X for my commercial subs and don’t use fasteners for our standard offerings. Not sure what the equivalent that would be on your side of the pond but we’ve tried quite a few types and PL Premium 3X is the one we like the best by far. We used to use Loctite Heavy Duty but we had a couple bad tubes I think so kicked that stuff to the curb. I believe most use true Baltic Birch plywood, which is significantly better than standard plywood (13 void-free plys in 18mm vs inconsistent layering). The true Baltic Birch I get for my business is from Russia/Ukraine and less than $50 USD in bulk for 1520mmx1520mmx18mm sheets. This is definitely the best plywood for building speaker and sub enclosures. You could use MDF but I don’t like it, it’s heavy and won’t hold up if dropped and doesn’t hold screws well.

Trying to recreate the old Maxell ad? Just a little bit of output capability there.

The Skram would definitely give you some chest pounding bass but I’d still suggest considering dedicated midbasses to give you control over the entirety of midbass from 60-200/300. Even though my subs play up to 200 Hz, I built some midbass units based on the JBL 2226 drivers and I was very happy I did. This lets my subs play more in their sweet spot as well as keep their directionality out of it while being able to dial in as much midbass as I want. You mention you have other sub drivers for deep bass, I assume they should be able to play up to 60 Hz so the Skram almost seems like you wouldn’t need/use its full capabilities anyway. And the Skram, while smaller than Ricci’s other offerings, isn’t exactly a small enclosure, so you’re putting some big units in to play a fairly narrow band of the frequency range. The Skram would definitely be fun and maybe you just want to play with it but based on the limited info, I’m not sure you’d get the most out of it with your current configuration but then again, configurations change. Maybe you build the Skram and decide you don’t need the subs currently playing deeper. Playing with equipment (options) is sometimes as much fun as playing the equipment.

Wow. That would definitely get down into the single digits with 1 vent open. Nice. Any issues with port velocity with only 1 vent open?

Why don’t you look into a dedicated midbass instead of using a subwoofer to play that high?

Depends on what you’re looking for. I’ve measured my 24s in many rooms and they’re flat to 7 Hz in-room with over reference level output. The 21s won’t achieve that in a Skram but they’ll run away from my 24s above 25Hz I’m sure. Some don’t worry about under 20Hz content while I will never go back to subs that can’t provide solid 10 Hz output. So it really depends on what you want and your circumstances. If you’re on concrete and can’t put down wood, you won’t get as much tactility so it may not be worth chasing under 20Hz. But if you’re on a wood floor, the deep bass imparts some really nice tactility through the floor during movie explosions. Also depends on the size of the room you’re trying to cover and number of Skrams you’re building. 4 Skrams in a small room like some seem to be doing will probably have quite a bit of under 20 Hz output but would have so much headroom above 30 Hz that wouldn’t get used if under 20 Hz is the goal. So just depends on the goals as there are many, many ways to get there. One other thing to note is I recommend multiple “lesser” subs (18s instead of 24s::)) in a room to get more even bass. If you have a sub, turn 1 (only 1) on and walk around the room while playing. You’ll hear some areas, especially the corners, where the bass is stronger and maybe boomy while other areas don’t have as much bass. This is your room interacting with the bass waves. To combat this, Harman did extensive testing and found 4 subs placed in the 4 center walls of the room was about the best (diminishing return over 4 subs) followed closely by 4 subs in the corners. So if you’re only planning 1 uber sub, I’d strongly suggest against that and to go with multiples so you’ll get more even bass. Note that long rectangular rooms may need a couple of fill subs though room simulation software would need to be used to identify this.

Which Vancouver? If The Vancouver, then he’s on the other side of the US.

I really liked Brandon’s SH50s but wish the high-end was more detailed and didn’t drop off before 20,000Hz. The staging was incredible but it was just missing the detail and extension of other speakers I’ve heard. It’s a shame Danley haven’t put out a dedicated HT version as I’d think it would be a very good seller. But I understand as a business they may not want to go that direction or have too many other focuses. Too bad for us.

I also wonder if a single piece of .75”/18mm plywood is strong enough for such a big and powerful driver. I usually use a minimum of 2 layers of .75” plywood for my subwoofers and usually 3 for larger drivers (18”+). If the driver is moving the baffle it is mounted to, you will lose efficiency/output.

Jesal, I realize the SH50s are very capable and you want a subwoofer system to match...but really...more? Lol!

No worries man. If you need 100 or less, I can send them out. If you order 500 like DS1 did one time, I’ll give you links to order directly, as he cleaned me out. Order info is below though you'll need to PM for my PayPal address. https://www.avsforum.com/forum/155-diy-speakers-subs/2258906-what-fasteners-you-using-big-drivers-3.html#post40276266

If you did want to use an insert on the back, this is what I use on my subs and it works very well. No concerns like I’ve dealt with before using T-nuts. https://shop.stafast.com/sl14205h2170

And. MiniDSP has sometimes caused noise issues in the signal chains of home and car audio systems so if you can keep the signal chain simpler, I would. So my vote would be the DSP version. The Peavey IPR2 amps are more powerful than the iNukes but they’re also a lot more expensive. So if it were me, I’d probably still buy the iNuke DSP but might move up one model to ensure I had headroom with the needed power. But I don’t see why you’d buy 1 amp for 1 sub when the next step up with both channels could comfortably drive a subs on each channel.

That is absolutely ridiculous and somehow I like it.

I see your point that our 18” is in a slightly smaller enclosure than optimal but so is the 24. So I’d say it is an apples to apples comparison but it might be nice to see an oranges vs oranges comparison but that’s up to Stereo Integrity and Josh to address. I’m game for a review. Tried to get Josh to review last year but he was too busy and I haven’t bothered him this year.

A single DSS Mariana 24S sub with 4,000w beats a pair of Mariana 18S subs with 8,000w though you’d have to have measuring equipment to notice the additional 1-2 Hz deeper (at reference the 24 is flat to 6/7 Hz in the dozen or so rooms I measured) or the 1-2 dB louder it plays at some frequencies. Enclosure wise the Mariana 24 is 8+ cu.ft. and each Mariana 18S is 3+ cu.ft. Cost wise, a pair of Mariana 18S subs cost a little more with the SpeakerPower plate amps being the largest cost. While a single Mariana 24 plays a little deeper and louder, I usually try to push prospective customers to a pair of 18s as they’ll get more even bass in a room, which I know isn’t necessarily a top priority on the pro audio side.

I just wish they'd put an actual frequency response, as opposed to "Effective Frequency Range". But interesting design, especially the battery operation for such a large device.

Yep. https://spacemath.gsfc.nasa.gov/weekly/6Page53.pdf I primarily use metric for my designs, which was primarily driven by my purchasing a Festool track saw over a decade ago. I have no clue why the US doesn’t join the rest of the smart world in switching to the metric system but there’s no discussion of that, I guess the US has too many other problems to try to solve.

You guys are lucky that construction quality is that good. Even following code, construction is often not that great depending on where you live in the US, so if you’re in a normal apartment in the US, I doubt you could have even a Sb16 without getting into trouble even on low volume. Now bigger/taller buildings might have concrete floor construction and likely wouldn’t bother neighbors as much but that’s definitely not the norm where I’m at. Looking good and sounds like a good plan.