Ricci

Honestly some stiff foam cut to shape works just fine for an easy route. Similar to what the ID MFG's do for variable tuning.

There are 4 ports when all are open= Divide the Ap (port area) of 725.76cm2 / 4 = Each port has an area of 181.44cm. Multiply 181.44 by the number of ports that are open and input into Ap. Also some volume from the vent is added back into the enclosure when blocked. Add 14.42L to the enclosure rear chamber volume (Vrc) for each port that is closed off. 3 port operation = an Ap of 544.32 and a Vrc of 216.15 2 port operation = Ap of 362.88 and a Vrc of 230.57 1 port operation = Ap of 181.44 and a Vrc of 245

DXF files uploaded to the first post...

I'm surprised they ran like that. It's not making sense to me how they would have a complete circuit using both positive terminals in stereo mode? It's kinda hard to make sense of what you are describing. At the end of the day if the amps and speakers both still work afterward then there's nothing to worry about. Just pay more attention next time!

Looks somewhat similar to a design I had a few years ago but ended up going in another direction. IF it's the one I've seen a few screenshots of. Good luck in the endeavor. As far as this Eminence driver goes I hope they get their stock built up soon. I need that 2nd pair eventually.

SME's post is spot on. It takes careful investigation to figure out where clipping is occurring. MiniDSP's are not known for having robust voltage headroom on either the input or output. EQ complicates matters. Many receivers will clip the sub output internally under a WCS signal and well below maximum output voltage. The amp is the easy part of the gain stage. Most have clip indicators and as long as the gain control is up a few clicks from the minimum the input won't clip before the output.

Great fabrication work buddy.

Damn bro...It's been a long time.

Thanks guys...

Sent.

For whatever reason I cannot get the DXF to attach here even though I had no problem with the Othorn, GH, Skhorn, etc... You can pm me your email address and I'll email it to you.

I'd heard roughly $1000 MSRP. If the street price really ends up at $749 I can see them selling a ton of these. Do you mind if I ask where you heard this?

Subscribed for the fancy port work if nothing else. 😂

All comments above about the SHS-24 above generically apply to the HS-24. The output you are looking for in that frequency range really comes down to moving huge amounts of air. Both SI 24's excel at that.

They are both sealed subs so all output comes from the driver displacement. The enclosure volumes are close enough to disregard those differences. The SB13 fails for distortion a full 3 or 4dB before it's actual maximum output is reached. The amp should not be a contributor to distortion at all below 25Hz for the SB13. It really just comes down to the driver design and the behavior of it at high excursion. The F113 driver is clearly more linear and lower distortion at much higher displacements. If both subs are driven to the absolute limits and distortion is ignored the SB13 is within roughly 1dB of the old F113 (current v2 version may be improved), but clearly the F113 driver is behaving better.

Yep...Rather than getting too wrapped up in thought exercises on ways to test this and accounting for things like ambient air temps, conduction, convection,etc...It really is this simple. A DSP limiter tied into feedback from a temperature sensor in the former or motor, may be the future.

Ported would be easiest and smallest. 21DS115 might just barely get there if tuned to 13Hz or so in a big cab but it'll be at the hairy limits by then. Unless you go with a GIGANTIC FLH. SHS-24 will probably damn near get there sealed. I've got a pair myself. It'll take a monstrous power amp to get it there in a sealed cab though. Build a big ported cab for it tuned to 13Hz and it would easily get there with some left in the gas tank. That's probably the easiest option.

It will change the tuning and restrict the air flow. I wouldn't recommend it. That's why I didn't put any handles there.

That would be interesting to see. I'd chip in if someone wanted to do it. Too bad I don't still have the old AETechron 7560's / Crown M600's. DC coupled amps for running MRI and other medical equipment that would legit dump around 1000w into very low impedance loads and they could be ganged up in pairs. perfect amps for that. Wouldn't have to be the highest power handling sub on the market. Something reasonably cheap and beefy. Bonus points if it is easily factory repaired or re-coned. An Orion HCCA is relatively cheap, has a big 4" coil and recone kits are cheap and easy to find. I think they say it's a 2500w driver. If just running DC current there really isn't a need to have the whole driver even. Just run the coil of a re-cone assembly and monitor the temps and at what point it starts to burn. It won't be surrounded by the motor and frame structure but it also won't be moving through the air like it normally would. Start at 50w and increase by 50w at a time and let the temp stabilize in between. It won't last long.

Since we are discussing some type of HIL related rating here...I'd like your opinions. Should I use max burst for it, which will tend to favor passive systems at the higher frequencies due to the absurd amount of amplifier on tap, or use the max long term sweeps which will be more granular and more fair between turn-key systems and the passive stuff, but may under represent the actual dynamic potential by a large amount? Alternatively should it be discarded altogether? Too much work, not enough pay off, too confusing for casual enthusiasts?

+1 Home audio has it easy with a relatively stable environment. Outdoor pro audio work at festivals and the like is a whole other deal. The worst is car audio. 100+ deg temperature variations, random humidity and barometric pressure, road noise, etc...Forget that tightly dialed in DSP.

That's another caveat with the APPL rating I meant to mention. How to deal with odd shapes and curved sides? They will get shafted a bit. It's not feasible to physically measure and calculate that stuff on my end. Perhaps the MFG could. Anyway this type of output density rating is really just for "learning" rather than salesmanship to consumers. They have a ton of other usually more pressing considerations like, cost, looks, warranty service, availability, etc.

I've been mulling over a HIL type of metric for a very long time. Years...There was some discussion here at some point a while back. I had all of the data already I just needed to decide what are the appropriate measurements to use and what is the appropriate way to parse and present the data. After that it's a matter of extracting it and adding it to the DB site. I always thought it would be interesting to have a metric representing which units have the most output from the minimum size. I decided to use the maximum burst output rather than distortion limited burst for a couple of reasons. Distortion levels are dramatically affected in rooms and vehicles. Also when listening to a system we don't have an exact cut off for distortion or noise the way CEA-2010 does. It's subjective and varies by person. Some apps may not care about a distortion limit at all (Car audio SPL comps). I thought about using the maximum long term sweeps as this would produce a more level playing field between turn-key systems and the passive cabs. Problem with that is those sweeps often involve a significant amount of compression so are not a good indicator of the true short term output. The data is presented in a way that indicates the measured, maximum, short term output, at each 1/3rd octave band, normalized per cubic liter of volume. The data is converted to Pa and then divided by the volume that the DUT takes up in L. This is then presented in Pascals per liter. 1 Pa is = 94dB SPL. A rating of "1" in even the 125Hz bandwidth from something the size of 1 cubic liter would be a tremendously powerful and output dense system. HIL is still baked into the results. Ratings down below 20Hz are way lower than at 125Hz. I may need to compensate each frequency band so that a "0.3" at each bandwidth has the same relative weighting. I haven't thought too much on that yet. I'm tentatively calling it A.P.P.L. or acoustic power per liter. The point of the rating is that the most output "dense" systems at each bandwidth could be determined. Also the ratings would be directly comparable. You may wonder whether a vented 18 gets outperformed by a stack of 6, 8" sealed subs, or some other outlandish scenario. It's easy to determine. If the APPL rating is higher on the 8" sealed than the vented 18 a pile of the 8's in the same volume as the vented 18 would have more output at that bandwidth. Obviously this type of information would be of limited use to most consumers but it should be a fun comparison tool for the data nerds and system designers out there. Making comparisons this way does have some very large caveats though. It does nothing to consider the cost, weight, power requirements, or number of outlets required. A pile of smaller cheaper subs may potentially out perform a larger single unit from the same amount of space, but it might require 6 power outlets, a couple of extra breakers, they could cost 3X as much, or they might weigh 3X as much. Anyway I've been adding this graph to some of the systems and I'm about 2/3rd's there. The ones that I have done should be visible now, but I'd consider these preliminary pending some further thought on some type of compensation at each frequency band and possibly a sortable chart of all systems similar to what we have for max burst and CEA-2010.

Man...You are having a time of it lately! It sounds like you don't have enough cabs to provide the level and duration you are looking for. What drivers were the 15's? Amp is Behringer NU3000? I assume these were midbass modules?

Single digit sine waves are some of the worst. Impedance is very low so current input is high. Technically there is a lot of cone excursion but it is a very slow oscillation that produces low velocity air movement across the coil and through the motor structure. Be careful with that stuff!