Soundqubed

Pretty vague on the vehicle or space, inverted is your choice. I've found thru testing it can affect output. Its a show your magnets thing imo... not cooling. 3-18s is a big mamajama, my thinking is it should be 16.5ft3 net minimum or so /w/300in2 of port. I'm talking about 25ft3 external /w/ single ply 3/4" double baffled braced heavily. Inverted or normal mount is 6/5 and pick em' im my exp
Its going in a 2004 yukon denali
 
Thanks buck for your feedback. Its going in a 2004 yukon denali...def will probably have them mounted regular firing up. Do you have any ideas on the port.
I'm not exactly which version of the sub you have, but usually something like 6 cubes per woofer would work well, So maybe 18 cubes net airspace at idk 32 hz with like 14-16 in^2 per cube of port area, like 250-290 in^2 total, depends on how you tune it, exactly.
 
I'm not exactly which version of the sub you have, but usually something like 6 cubes per woofer would work well, So maybe 18 cubes net airspace at idk 32 hz with like 14-16 in^2 per cube of port area, like 250-290 in^2 total, depends on how you tune it, exactly.
Yes sir its the hdx3 version not the 3.2 yea was thinking about tune at 32hz as well. was thinking of putting the port facing out towards the rear cargo door at bottom of box
 
Yes sir its the hdx3 version not the 3.2 yea was thinking about tune at 32hz as well. was thinking of putting the port facing out towards the rear cargo door at bottom of box
If you can fit it, yes. Make sure to leave enough room for port to breathe, sometimes big boxes, the edges of the box can limit airflow. If you run out of room and need the extra depth you can up fire the port up at the back near the hatch/cargo door, that def works too.
 
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If you can fit it, yes. Make sure to leave enough room for port to breathe, sometimes big boxes, the edges of the box can limit airflow. If you run out of room and need the extra depth you can up fire the port up at the back near the hatch/cargo door, that def works too.
Good idea I didnt think of firing the port up....
 
Good idea I didnt think of firing the port up....
I've done it in many vehicles. I have pics too, idk if you have instagram but I designed for people here and there over time, did 2 Fi 18 woofers like 9000w rms total had port at rear firing up, many broken windshields still. Done the same thing for 4 15's, 4 lower powered 18's, works well in smaller cabin cars too, hatchbacks, wagons, etc.

You have so much freaking cone area with 3 18's that it's going to pressurize whatever you put it in well, you just want to put your port in the vehicle like your vehicle is another box itself, as in put the port at the back of the vehicle to let the wave flow from front to back smoothly, like a transmission line type enclosure, if you can visualize that. Smaller enclosures maybe firing port back or all back would be advantageous to help loading around the radiating surfaces, but 3 18's is so much radiating area plus the port, I've seen firing up work very well, if you have to. Sometimes the extra space you can get for firing up is worth it. But idk, that's so much bass no telling what it'll do to the vehicle. Your hatch and whole vehicle is going to take an absolute beating if you do this right.
 
I've done it in many vehicles. I have pics too, idk if you have instagram but I designed for people here and there over time, did 2 Fi 18 woofers like 9000w rms total had port at rear firing up, many broken windshields still. Done the same thing for 4 15's, 4 lower powered 18's, works well in smaller cabin cars too, hatchbacks, wagons, etc.

You have so much freaking cone area with 3 18's that it's going to pressurize whatever you put it in well, you just want to put your port in the vehicle like your vehicle is another box itself, as in put the port at the back of the vehicle to let the wave flow from front to back smoothly, like a transmission line type enclosure, if you can visualize that. Smaller enclosures maybe firing port back or all back would be advantageous to help loading around the radiating surfaces, but 3 18's is so much radiating area plus the port, I've seen firing up work very well, if you have to. Sometimes the extra space you can get for firing up is worth it. But idk, that's so much bass no telling what it'll do to the vehicle. Your hatch and whole vehicle is going to take an absolute beating if you do this right.
Thats what I like to hear i am an old school bass head lol. Me and my dad use to do the db drag racing back in the day and I was a die hard rockford guy back in the mid 90's so getting back into it and wanted one more big build. This is my old build we ran was an 8 cubic ft box with 21 Inch port...had 2 t2 rockford 15 dual 2ohm on 2 bd t500.2 and 160.4 channel rockford running my component system. Was hitting in the 144 because is in a 95 nissan extended cab.... so I really wanted this build to definitely slam harder than that which it should lol blow it out of the water.....
 

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Thats what I like to hear i am an old school bass head lol. Me and my dad use to do the db drag racing back in the day and I was a die hard rockford guy back in the mid 90's so getting back into it and wanted one more big build. This is my old build we ran was an 8 cubic ft box with 21 Inch port...had 2 t2 rockford 15 dual 2ohm on 2 bd t500.2 and 160.4 channel rockford running my component system. Was hitting in the 144 because is in a 95 nissan extended cab.... so I really wanted this build to definitely slam harder than that which it should lol blow it out of the water.....
My best system was 2 dc xl 18's in 13 cubes at 29 hz, doing 149.3 at 35 hz on 2400-2600w rms total. Subs up port back explorer. To get that though I had my hatch braced and foamed and wood panel bracing on my roof and sun roof sealed up, a lot of sound deadener. It was still ripping my hatch sheet metal, had to have it welded, rear window literally fell out. Been years ago:



But yeah if you have proper power and do a super proper box you should easily be over 150, unless your vehicle just falls apart. I'd also do like I think shredder said and double layer that box up, if you can, or will need quite good bracing, good flow design too. It needs to be a whopper of a box, don't skip on strength. It's so hard to say a score because once you get into super big systems, the vehicle flexing is where you start getting the biggest losses. I mean you could maybe be near 155 or so with this system, but only if the vehicle holds all of it, everything is done right.
 
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My best system was 2 dc xl 18's in 13 cubes at 29 hz, doing 149.3 at 35 hz on 2400-2600w rms total. Subs up port back explorer. To get that though I had my hatch braced and foamed and wood panel bracing on my roof and sun roof sealed up, a lot of sound deadener. It was still ripping my hatch sheet metal, had to have it welded, rear window literally fell out. Been years ago:



But yeah if you have proper power and do a super proper box you should easily be over 150, unless your vehicle just falls apart. I'd also do like I think shredder said and double layer that box up, if you can, or will need quite good bracing, good flow design too. It needs to be a whopper of a box, don't skip on strength. It's so hard to say a score because once you get into super big systems, the vehicle flexing is where you start getting the biggest losses. I mean you could maybe be near 155 or so with this system, but only if the vehicle holds all of it, everything is done right.

Yea I was already contemplating the wood panel bracing in the denali. I def think I will need to get that done. Also later on was thinking about strapping another 4500.1 to these 3 subs because the specs have it rated at 1500rms but burp at 4500peak . Already have ordered a mechman high output alternator will be 400amps. Also plan on doing focal 3 way 165as 2 sets for my highs and mids runn off a focal 4.600v2....
 
Yea I was already contemplating the wood panel bracing in the denali. I def think I will need to get that done. Also later on was thinking about strapping another 4500.1 to these 3 subs because the specs have it rated at 1500rms but burp at 4500peak . Already have ordered a mechman high output alternator will be 400amps. Also plan on doing focal 3 way 165as 2 sets for my highs and mids runn off a focal 4.600v2....
Your vehicle I'm pretty sure is easy to get multiple alt mounting bracket too. You can run factory alt and run 400 on top of it. That's what someone I know did he had Tahoe I designed many boxes for, he had triple alt, 2 for system and left the factory one the way it was.

With strapping you just have to make sure your ohms are right. Strapped will be at 2 ohm final load or so, my 2 18's where powered by 2 ed 9.1's strapped at 1.4 ohms final load. It cut out sometimes on lows or hard punches from combo of box being a little too big and wired at 1.4 instead of 2 ohms.

Soundqubed subs seem to be pretty linear, I've worked a ton with SQ/AQ, American Bass and DD, which were all somewhat similar as far as boxes went for many years. It's changed some but I bet most SQ 18's take the same airspace, you'd want to check on that though. So what I mean is that the box if you build it well enough could probably have the 2500w versions of those 18's just dropped in it when you want an upgrade or whatever 18 they have that's bigger. You could design this box to make sure it would work with the extra power as well, probably.
 
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Your vehicle I'm pretty sure is easy to get multiple alt mounting bracket too. You can run factory alt and run 400 on top of it. That's what someone I know did he had Tahoe I designed many boxes for, he had triple alt, 2 for system and left the factory one the way it was.

With strapping you just have to make sure your ohms are right. Strapped will be at 2 ohm final load or so, my 2 18's where powered by 2 ed 9.1's strapped at 1.4 ohms final load. It cut out sometimes on lows or hard punches from combo of box being a little too big and wired at 1.4 instead of 2 ohms.

Soundqubed subs seem to be pretty linear, I've worked a ton with SQ/AQ, American Bass and DD, which were all somewhat similar as far as boxes went for many years. It's changed some but I bet most SQ 18's take the same airspace, you'd want to check on that though. So what I mean is that the box if you build it well enough could probably have the 2500w versions of those 18's just dropped in it when you want an upgrade or whatever 18 they have that's bigger. You could design this box to make sure it would work with the extra power as well, probably.
Yea im running into a problem with my 3rd hdx 18 dual 2ohm. I have 2 already brand new in the box never played and ordered a 3rd December 4th just for the company to contact me yesterday and say that they are out of stock. Company was gately audio. They are refunding my money but here is my dilemma both my subs are dual 2ohms which that 4500.1 is 1 ohm stable and it isn't .5ohm stable and I wanted to get the full power out of my amp. I'm think about getting 2 of the older version hdx4 18 dual 1ohm which they are having a crazy closeout sale on them on sky high audio at 449 a piece. That way could get the full capability of my amp. What are your thoughts. And they call for the same air space as the hdx 3 of 5-7cuft in ported box
 
Yea im running into a problem with my 3rd hdx 18 dual 2ohm. I have 2 already brand new in the box never played and ordered a 3rd December 4th just for the company to contact me yesterday and say that they are out of stock. Company was gately audio. They are refunding my money but here is my dilemma both my subs are dual 2ohms which that 4500.1 is 1 ohm stable and it isn't .5ohm stable and I wanted to get the full power out of my amp. I'm think about getting 2 of the older version hdx4 18 dual 1ohm which they are having a crazy closeout sale on them on sky high audio at 449 a piece. That way could get the full capability of my amp. What are your thoughts. And they call for the same air space as the hdx 3 of 5-7cuft in ported box
I feel like running below what ohm the amp is rated for daily is risky. The hdx4's are good subs too imo, like two of those on 4500w could be very loud.
 
I feel like running below what ohm the amp is rated for daily is risky. The hdx4's are good subs too imo, like two of those on 4500w could be very loud.
Yea I think im going to just get the two 18 hdx4 1ohm and hold on to the hdx3 or try to sell them. Because the rms on the hdx4 are 2000 so they can handle more power and I think will hit hard on my 4500.1
 
Yea I think im going to just get the two 18 hdx4 1ohm and hold on to the hdx3 or try to sell them. Because the rms on the hdx4 are 2000 so they can handle more power and I think will hit hard on my 4500.1
And was thinking about a 14cuft box for the two...
Yeah that amp and those 2 should match up very well, I would think.

From my experience with several 18's, I'm a guy that likes heavy lows, so if I had those I'd probably tune to 28-30 hz in probably 12 cubes. 32 hz maybe more people would find that better, so that's all up to whoever for your tastes, but 7 cubes per woofer seems a little big to me maybe regardless of tuning. I've had several 18 boxes in my daily before, and to me 7 cubes makes the bandwidth fall off too hard, even if the sub handles it fine or is rated a range like yours being 5-7 cubes. 6 cubes is about perfect IMO, but do what you want, it'll be loud as f either way if all else is also proper.
 
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