Dimensions for sealed 18" sub box - Page 19

^ that's completely unnecessary, and worse, inapplicable to what I posted...I quoted part of your 5 paragraph post regarding incorporating mdf into cabinets. If it's "off the table" here, as you suggest above, why bother posting about it? This is after all a thead dedicated to the 18" cabinets you plan to produce. So when I question why a baffle composed out of mdf would look any more or less out of place than a brace within a cab otherwise entirely composed of BB I get the above? Lets talk about:

Most imperatively, yes, you have indicated that a cabinet can be made entirely of BB...but I have yet to read a post stating that's the way you intend to definitively proceed...others have posted here within hours on the very subject. If that's way you're going, great. Done deal, let's go!

As far as input: I think everyone has expressed their views ad nauseam at this point re drivers, cabinet composition, universality of driver openings, etc... there's no reason to even consider the contrary. If people have not responded with any additional information you have requested, I'd be it safe that the demand in that particular area to be low...at least here on the AVS diy forum.

James
Edited by mastermaybe - 11/14/12 at 8:40am

just to kick a random idea into the mix...

would it make any sense to use regular ply/auraco for the bracing? it isn't going to be seen and that would free up the 5x5 baltic for all external panels including a double front baffle and allow for keeping the beefy bracing that will help market the enclosures.

we talked about bracing before and you rightly pointed out that it is not just about maximizing efficiency, it is in part making something that looks cool too. #2 hits the mark on both fronts. while i'm sure it would perform just fine, #1 just doesn't look as cool.

that said, i would recommend either one.

Good idea on the standard PW or auraco, but my hunch is that if mdf is objectionable for internal bracing, either of these will not fare much better.

On the "cool meter", 1-10, my bracing can sit at a "1" so long as it functions as it should, lol.

But if internal bracing that looks cool sells more boxes for Erich I'm on board with that too.

James

^^^ agree. that is what erich and i discussed a while back.

"Different batches of ply (even the best of the best) can vary by about .015 in thickness."

ah. roger.

"One more question: Are there any suggestions on what driver to put in a box around 2 cuft?"

the rss315hf will work with the plate amps and settings that i mentioned in my note a few weeks back.

^^^ right back at you erich. :-)

If you don't think there would be much interest in a big box for 15" woofers I wouldn't blame you for not making any. But Dayton actually recommends 5 cu.ft. for the RS and Titanic 15's. Is making a cabinet intended for 18's (is that what the 4.5 will be?) but with cut-outs on the baffles around 14" be a possibility?

If so, a 24" H X 18" W X 24" D would be very cool! One brace down the length (making two 9" sections), and two across the width (for three at 8").
Edited by BDP24 - 11/14/12 at 10:36am

My point is and was: if you HAVEN"T received such information, you can prolly make a safe assumption that there's not a lot of interest in them. Talk is cheap, I'd reason that if people were serious (as they seem to be regarding the 18's) they'd be offering up proposed dimensions/displacements.

Re the 18's: I suppose I'd have to go back and check but I thought Ricci had posted that nearly all the major 18" drivers can utilize the identical cut-out. Perfect.

Then, I think he suggested a handful of cab sizes that would work splendidly with the said drivers. Again, many agree and it seemed like a near perfect route to take.

What else would you like to know re 18" cabinets?

Regarding the 15"s: again, if you're not getting much feedback on them, is it completely out of the question to consider if it's worthwhile to pursue them? Part of my reasoning to cut (4) baffles out of a second sheet of BB was that it would (before I learned of your plans to produce them elsewhere in the chain) dramatically slow the production of 15" cabs that I- gauging from this thread only, primarily- don't anticipate to be nearly as popular.

If I'm off-base re the nearly universal 18" cutout and suggested cab dimensions from Ricci please forgive me, I'm working off my recollection.


James

This.

I'll dig out the cut-outs for a myriad of 15" subs if I can help. Perhaps we'll find a similar case to the 18" scenario: that most will fit within a "standard"...it sounds like there's a damn good chance of such a reality judging on Josh's last paragraph in the above post.

Mods can easily be made to reduce cabinet volume is so desired.

To me, this is the perfect appreciation for the KISS principle.

James

Erich- coming from the guy who's prolly been the hardest on yah - I think you're really doing a great job here and, if anything- are maybe attempting to be a bit too fine.

this IS DIY afterall and you're already doing the lion's share of the heavy lifting. If people want to take it another step or two, I'd suggest letting THEM take it the rest of the way.

I'd guarantee you that no one on this thread will be anything but immensely thankful.

James

Ok, before this goes too much further...

You shouldn't have to alter ANYTHING...at least as far as the 18" goes. Ricci has already insisted that all the 18" will work with the same cutout...if it's going to be in-set, simply make sure the outer baffle is large enough to accommodate the driver with the widest mounting flange. I'd bet the WIDEST is no more than 1/16" wider than the narrowest.

From THERE, people can modify if they choose. Perhaps offer a larger cab if there's that much of a demand for it. Again, it should be drop and screw for all of the 18" drivers.

"I did read Ricci's post and he's right. That's why the 18" LMS box is getting done That method will be fine on some models, but the driver will be sitting on the outside sub flange, which some people would rather not have with the smaller sizes.

I just want to make sure that the original design for each box size has a specific driver that it will fit. That way people will see a complete kit they can order. Then if it happens to also work for some different woofer with a different outer baffle, that's fine too."

I will admit that I'm simply not following a bit of this.

the "outside sub flange" has me a bit puzzled. Do you mean it would be very near the inner diameter of the first baffle cut out or that it (the mounting flange) would rest above the inner baffle, on top of the outer baffle? The latter doesn't make sense to me as there would be no reason to make the outer baffle that small.

Onward, ALL of 18" drivers should fit the same cut out, so why would there be a need to make any "driver specific"? Simply list the cab and the 18" drivers that it can accommodate right with it. Offer a second size (cabinet) if doable.

James
Edited by mastermaybe - 11/14/12 at 11:38am

"my design" lol?

I'd offer a 3.5 and 4.0 cube and be done. All I need to know is that the 18" drivers are nearly interchangeable. Again, account for the difference (if any) in mounting flange diameters and ensure the outer baffle can accommodate them.

done!

James

Good deal. I'm a fan of arc type bracing, when pillars in the panel centers are not an option due to the driver motor.


I think maximizing the size of the enclosure out of that single sheet is a good idea for the dual 12". For a single 15" cab the best choice would probably be to maximize what you can get out of one sheet as well.


I gotta admit I'm confused Erich.

I think you are approaching the designs the wrong way and trying to make things FAR too specific. There should be a couple generic designs and that is it. Not 5 different 15" and 18" baffles and different sizes that vary by 0.5cu ft. This unnecessarily complicates things.

The difference between a 3.5 cu ft and a 4 cu ft sealed box for an 18" driver is negligible in the scheme of things. It certainly does not warrant a completely different kit and cnc program IMHO. The LMS works great in 4 cubes. So does the RS18 HO and the UXL and... What I'm saying is make the 18" sealed cab fit however it does best from a cutting and materials perspective. If it ends up at 3.5 cubes fine, if it ends up at 4.5 cubes great...It will work for the majority of HT drivers people use. You don't need 3 different cabinet volumes for 15's just 1 that works for most.

Why are there going to be specific baffle cut-outs for each individual driver? You aren't pre-drilling mounting holes are you? (Do not.) If it is just the cutout on the inner panel and the frame cutout on the outer baltic mdf carbon fiber glass composite concrete panel, then you really only need 1 universal cut out for 15", 1 18" and 1 12". These should be used on all of the boxes. Option 2 should be blank baffles for each box. If MaxxBassThunder150 joins AVS next month and wants to use your kit with his off size JL 13W7 or XXX 15 he can order the blank baffle and cut it his self. I don't see the problem there. You can't cover every driver with 1 cutout size but you can get most of what's popular. Again not to sound like a broken record here, but you can cover every 15" from: Fi, TC, AE, Mach5, Dayton RS, Dayton Titanic, Stereo Integrity, 90% of Sundown, SSA, Ascendant Audio, Adire discontinued stuff, RE Audio subs except for current XXX, Exodus drivers...etc...With one cutout size. Get the dimensions for the 5 most common driver frames add 1/16th to the dimensions of the largest one and use that as your cut-out. For the frame cutout do the same thing with the rubber gasket on the biggest frame. the smallest ones might have a little play but they will work fine. The flanges on these are typically around 3/4". a 1/8th inch of play is not the end of the world and not worth complicating things with multiple kits and programs and complexity.

I understand this is more complicated than it seems. Truly I do. This is what I think makes most sense and keeps things the simplest. It's what I would do if I were calling the shots in your position. It's your show though I'm just offering my opinion. Eventually you have to decide and move forward on something. If you are looking for specific suggestions on drivers, cabs etc...what are they? You seem to want something involving the LMS and the Dayton RS 18. Here are my cabinet suggestions for these two. I would suggest the exact same 21" cube cabinet for both at right about 4 cubes after bracing and driver. Same baffles too.



This is the same baffle arrangement you are thinking of using one inner layer the driver screws to and one outer. These 4 drivers all have different frames. i know of at least 2 others that drop in as well. I have done nothing to change this box. It has had I don't know how many 18's mounted in it.

Dayton RS18-Ho


LMS Ultra


Sundown Zv3


RE Audio SX18

Edited by Ricci - 11/14/12 at 12:08pm

I totally agree with Josh. Keep it as simple as possible and avoid a lot of headaches.

^ yep to what josh just said.

I don't ever do this, but I will...

+ 1000 Josh.

As I mentioned, I thought things were getting needlessly complex on Erich and this pretty much lays it down from a bit of an authority.

James

I'm certain this is directed at me which is unfortunate because I'm looking to do anything of the sort. Neither is Josh with his essential "re-post" above detailing how what you're anticipating to be a problem should not be at all (thanks for the detail Josh, that I didn't take the time to get into).

I'll step away now.

Best of luck.


James

Ok...Erich,

I think what you are saying is concerning the outer baffle for the most part correct? In my opinion the recess for the drivers should always be the entire material thickness of the outer baffle. Always. There is no reason to do otherwise other than cosmetically as the surrounds on these protrude a large amount as seen in my pics. Now if you are concerned about the wood edge ring seen around the flange on the drivers like in my pics and want a truly flush finish from the frame edge to the baffle that is a whole other deal. (excuse the cab it has been in a few battles and was never meant to be pretty. ) You made a comment that seems to indicate this is the case and that is probably the cause of most of the confusion. I didn't know you were concerned with this and I'm sure a lot of others didn't pick up on that. I would personally not be concerned with having the flange thickness perfectly flush with the baffle but that is just me. Some guys have much higher visual standards than I.

Also you are correct, there is the large rubber trim ring used on a lot of subs and this adds a lot to both the thickness and the diameter of the frame. Mounting a driver without it such as the Dayton RS into a cutout for this rubber gasket it will be quite a bit smaller and look funny. Yes. Gotcha there. Note that I did not use the rubber trim ring on the drivers in my pics for exactly this reason.

Now we are getting somewhere. If guys want to use the rubber gaskets then this will not work with drivers not having it as far as for the outer baffle cut out. If you decide not to support use of this rubber gasket and just go by the true frame diameter then we are back to many many drivers being able to use the same outer baffle, provided that the thickness of the frame isn't an issue and true flush mounting with the outer baffle isn't required. I don't use the rubber gaskets with recessed drivers typically, for the exact reason above. I don't really care about true flush mounting of the frame lip either but that is just me.

It looks like at this point you should decide one way or the other whether ...A. recess mounting of drivers with rubber gaskets will be supported or not. And B. Whether you will attempt to make the outer baffle a flush mount rather than just a recess. I vote full 1 panel thickness recess regardless of actual frame thickness and NO to the rubber gasket in order to streamline and keep the boxes as simple as possible.

Oh and the random driver method should still use a full recess panel of the outer frame OD either with or without the rubber gasket whichever way you decide. No need to have it be a double thick baffle if not for a recess. If the outer baffle isn't a recess just save the extra wood and weight and go with a single layer and mount directly to that. Nothing else would be needed.
Edited by Ricci - 11/14/12 at 12:52pm

Now if you are concerned about the wood edge ring seen around the flange on the drivers like in my pics and want a truly flush finish from the frame edge to the baffle that is a whole other deal. (excuse the cab it has been in a few battles and was never meant to be pretty. redface.gif ) You made a comment that seems to indicate this is the case and that is probably the cause of most of the confusion. I didn't know you were concerned with this and I'm sure a lot of others didn't pick up on that. I would personally not be concerned with having the flange thickness perfectly flush with the baffle but that is just me. Some guys have much higher visual standards than I.

Well- without beating thy chest- I knew that was precisely what h was talking about but- personally- find it fantastically trivial, and I for one care a great deal about how things "look". I don't pull this opinion out of the air, but rather after considering how small the difference is likely to be and more importantly how that difference will appear on a finished cabinet.

But I'm a bit in the dark regarding the gasket on other baskets...adding thickness is one thing..."width" though??? Does the gasket actually protrude beyond the mounting flange??? If so, that's dreadful...and prolly unnecessary if I'm picturing it correctly.

Then, even if you had a "custom" baffle for those kinds of drivers, would not the "tightness" of the baffle up against the gasket have its own problems, potentially?

James

Yes , the rubber gasket used on a lot of drivers add width and thickness around the mounting flange. They are also a pain in the a$$ when installing in a close tolerance recess cutout. I personally dont use the gaskets anymore because of these reasons.