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Doesn't it freaking kill you guys when manufacturers don't list this number ???
Urgggghhh !

I get that it will be different depending on how the sub is mounted, face mounted, back mounted, etc, but this info is SO important, they need to tell me the displacement mounted 9 different freaking ways, and let me take my pick !

I know their are those who will say it doesn't make that big a difference.... But when I calculate everything else in my enclosures to the third decimal point.... Then get to sub displacement, what, I'm just supposed to toss that out the window ? Kind of makes the rest of my precise calculations pointless.

I have even called a few manufacturers who don't seem to be 100% sure of their own products ? Seriously ? Those freaking guys need to get a job at Home Depot ! At least their, nobody expects you to know anything.

Freaking kills me. How do you guys deal with this ?
Saw this posted in another thread, maybe it will satisfy your OCD.
 

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I'd sure like to know more about running two of these isobarically, also. Thinking more towards 4 cubes... which is still pretty small for two 18"s
Do you have any pics or info on your 15" isobaric test box? I'm very interested in this configuration and your results. What subs, power, & vehicle type are you using?
 

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Discussion Starter #24
Do you have any pics or info on your 15" isobaric test box? I'm very interested in this configuration and your results. What subs, power, & vehicle type are you using?
Hey someguy, well yes....
But let me preface this by saying, I've been kind of all over the place with my experiments, and now I'm feeling like one of my 15" subs might have an issue, causing what I "thought" was overexcursion :(
As it turns out, regardardless of the size of the enclosure, both the first 2.7 cube shot I will post, or the last version, of only 1.5 cubes, I'm still getting some funky voice coil sounds when cranked up close to full, whether it's bottoming out, or just hitting on one side or the other, I'm not sure ?
All of this said, the larger, 2.7 cube box here sounded the best... While the smaller 1.5 reduced that voice coil problem "a little".

Now trying to figure what I'm going to do with this monster 18" Skar sitting behind me 🙂 Order another and go for it ? Probably just order the amp first, if my money is burning a hole in my pocket 🙂
260481

Hmmm.
260482
 

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Perhaps you can clarify, but it appears the power wire for the externally mounted sub was sent thru the box. Is this correct? How did you seal that wire from airspace leakage?

If this is the case, I would suggest using a silicone bronze bolt with washers, or binding posts as an alternative. In both of these cases, the bolt or post is the conductive "wire" and you attach your sheathed wire with lugs to it. This method prevents any air leakage. It's not especially critical for a vented enclosure, but if sealed, it's better than simply running a power wire through a box.
 

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Discussion Starter #26
Well as I have said, this ended up only being a test box anyway, but the wire coming in the back of the box was sealed with silicone. The wire coming out the top was so tight I had to use pliars to pull it through. In a finished product, I'd make sure it was 100%.... But not my primary concern at this point.
In fact, I'm trying to decide if I'm going to rebuild this box with a passive radiator, or just go straight to two 18"s ?
 

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Discussion Starter #28
Well, it's going be one or the other... I just wish I wasn't having issues with one of the 15"s....

However, if I go straight to the two 18"s, I still need another sub, another PR, and an amp that can handle 1 ohm. Depending on what amp I go with, these 3 things could cost me $650 to $800.....Granted, I just made $800 yesterday for one 30 hr round trip of ride share 😉 Of course I have other things to pay for too...
 

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Doesn't it freaking kill you guys when manufacturers don't list this number ???
Urgggghhh !

I get that it will be different depending on how the sub is mounted, face mounted, back mounted, etc, but this info is SO important, they need to tell me the displacement mounted 9 different freaking ways, and let me take my pick !

I know their are those who will say it doesn't make that big a difference.... But when I calculate everything else in my enclosures to the third decimal point.... Then get to sub displacement, what, I'm just supposed to toss that out the window ? Kind of makes the rest of my precise calculations pointless.

I have even called a few manufacturers who don't seem to be 100% sure of their own products ? Seriously ? Those freaking guys need to get a job at Home Depot ! At least their, nobody expects you to know anything.

Freaking kills me. How do you guys deal with this ?
You waste time calculating everything on third decimal,.... have you asked yourself how much posted TS parameters vary from reality... they may be - 5-10%off or even more
Im pretty sure you will not hear difference in sound of your SW if you change enclosure volume up to 10%
Maybe you will be able to observe difference in result in peak SPL if you compete in SPL/dBDrag....
You probably dont have the exact measured transfer function of vehicleon which you are working on....
...
 

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Discussion Starter #32
You waste time calculating everything on third decimal,.... have you asked yourself how much posted TS parameters vary from reality... they may be - 5-10%off or even more
Im pretty sure you will not hear difference in sound of your SW if you change enclosure volume up to 10%
Maybe you will be able to observe difference in result in peak SPL if you compete in SPL/dBDrag....
You probably dont have the exact measured transfer function of vehicleon which you are working on....
...
Calculating stuff to the third point is not only easy, it's fun ☺ I agree it might not make an audible difference.... but if you are sloppy with multiple aspects, and each of those things add up, it "could" actually make an audible difference too. Your right that I might not know the exact transfer function.... which could also change things, which to me, is all the more reason to try to get everything else as close as I really can.

Anyway, I'm feeling pretty solid on going with .35 cubes for my 18 which will be mounted complete internally.... and only like .10 for both of the 15" passive radiators which not only have no motor, but will be surface mounted on a 1 1/2" baffle.....So I'm going with .45 for the sub and PR's. No braces neccessary, as the entire box will be doubled, and the top needs to be tripled, so their shouldn't be any issues with flex.
 

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Hey someguy, well yes....
But let me preface this by saying, I've been kind of all over the place with my experiments, and now I'm feeling like one of my 15" subs might have an issue, causing what I "thought" was overexcursion :(
As it turns out, regardardless of the size of the enclosure, both the first 2.7 cube shot I will post, or the last version, of only 1.5 cubes, I'm still getting some funky voice coil sounds when cranked up close to full, whether it's bottoming out, or just hitting on one side or the other, I'm not sure ?
All of this said, the larger, 2.7 cube box here sounded the best... While the smaller 1.5 reduced that voice coil problem "a little".

Now trying to figure what I'm going to do with this monster 18" Skar sitting behind me Order another and go for it ? Probably just order the amp first, if my money is burning a hole in my pocket View attachment 260481
Hmmm.
View attachment 260482
OAN... thought I saw two sets of RS225 in another pic a while back, but what are those in use now?

Man & Machine... Power Extreme!
 

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Hey someguy, well yes....
But let me preface this by saying, I've been kind of all over the place with my experiments, and now I'm feeling like one of my 15" subs might have an issue, causing what I "thought" was overexcursion :(
As it turns out, regardardless of the size of the enclosure, both the first 2.7 cube shot I will post, or the last version, of only 1.5 cubes, I'm still getting some funky voice coil sounds when cranked up close to full, whether it's bottoming out, or just hitting on one side or the other, I'm not sure ?
All of this said, the larger, 2.7 cube box here sounded the best... While the smaller 1.5 reduced that voice coil problem "a little".

Now trying to figure what I'm going to do with this monster 18" Skar sitting behind me Order another and go for it ? Probably just order the amp first, if my money is burning a hole in my pocket View attachment 260481
Hmmm.
View attachment 260482
OAN... thought I saw two sets of RS225 in another pic a while back, but what are those in use now?

Man & Machine... Power Extreme!
 

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Discussion Starter #35
OAN... thought I saw two sets of RS225 in another pic a while back, but what are those in use now?

Man & Machine... Power Extreme!
Well, I have them in the truck still, and they sound good... It's just that when I really beat them, I get a little voice coil hitting noise.
I could always throw the 10"s back in temporarily.
Actually, my GF has been driving the truck more than me (her car was in the shop) and she doesn't ever crank it like I do... So for now, it's not a problem.
 

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Well, I have them in the truck still, and they sound good... It's just that when I really beat them, I get a little voice coil hitting noise.
I could always throw the 10"s back in temporarily.
Actually, my GF has been driving the truck more than me (her car was in the shop) and she doesn't ever crank it like I do... So for now, it's not a problem.
Guess I should have specified.... what are these in the this pic:



Man & Machine... Power Extreme!
 

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Discussion Starter #37
Oh
Guess I should have specified.... what are these in the this pic:



Man & Machine... Power Extreme!
Oh.... Those are just some lightweight little 8"s that I'm giving from about 80-400 hz. Really lightens the load on all my mids and highs up front. They help a lot too, if I'm playing some old-school stuff, that doesn't have a lot of deep bass.

Edit, wait... You meant what brand specifically ? Honestly, I don't even remember... But they were like $15 each from Parts Express 😄 lol Sound okay though.
Maybe even better than the RS225's ?
 

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Reason I ask is because they look very familiar. I ran some Titan 8" for midbass I got from a P.E. buyout sale and was tickled with the response and output in my truck doors. They look just like the those. Can't remember what I paid for them but they were very inexpensive as well. I crossed them similarly... 100-400hz with shallow slopes.

Man & Machine... Power Extreme!
 

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Discussion Starter #39
Reason I ask is because they look very familiar. I ran some Titan 8" for midbass I got from a P.E. buyout sale and was tickled with the response and output in my truck doors. They look just like the those. Can't remember what I paid for them but they were very inexpensive as well. I crossed them similarly... 100-400hz with shallow slopes.

Man & Machine... Power Extreme!
It's been a few years, but Titan sounds familiar. And they were on a closeout too 🙂
 
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