JD1000/1 and impedance rise question!!

[Doxquzme Premium Member]

Put one of these in a 1.5 cu ft box, tuned to 30-33 hz, give it 1000 watts, sit back and enjoy! https://stereointegrity.com/product/sql-12-series-2/ -------------- Here is the perfect box.
33hz

Box External Dimensions Width x Height x Depth	24.00" x 13.00" x 16.92"
Material Thickness	0.75"
Net Internal Volume	1.50 ft3
Tuning Frequency	33 Hz
Port Area	24.00 inch2
Port Inlet Width x Height	2.09" x 11.50"
Port Length	33.57"

Example (not the actual box)

 

[Jimi77 Premium Member]

If you're chasing db's the best solution is more cone area.

 

[1point21gigawatts]

Hi there.

Got my system clamped.
JD1000/1 pushing a 12" CompQ DVC4 wired to 2ohms.

My JD1000/1 is 1000w rms at 2ohm stable. No stability at one ohm.

Clamp reveals 537w at 4.0Xohms.

Since this is contingent off of the box, cabin, car, etc, CAN I replace my DVC4 with a DVC2 to wire it to 1ohm, knowing that it will see a 2x rise and effectively be at 2ohm so the amp can push out it's full 1000w? Would this still be stable for the amp?

Another alternative is switching amps(and likely sub too), but I'd rather just switch out one component if I can.

You are good where you are at. The only thing that you can do is build a better box. Clean up ground too. 2x rise is normal.

 

[1point21gigawatts]

Put one of these in a 1.5 cu ft box, tuned to 30-33 hz, give it 1000 watts, sit back and enjoy! https://stereointegrity.com/product/sql-12-series-2/ -------------- Here is the perfect box.
33hz

Box External Dimensions Width x Height x Depth	24.00" x 13.00" x 16.92"
Material Thickness	0.75"
Net Internal Volume	1.50 ft3
Tuning Frequency	33 Hz
Port Area	24.00 inch2
Port Inlet Width x Height	2.09" x 11.50"
Port Length	33.57"

Example (not the actual box)


View attachment 61286

Good specs, wrong design. Kudos. Hold up.
Port specs- 3”x8”, 14” port length.
Box specs. 9.5” height, 16” width, 14” depth.
Sub up/port back.

 

[1point21gigawatts]

 

[1point21gigawatts]

Good specs, wrong design. Kudos. Hold up.
Port specs- 3”x8”, 14” port length.
Box specs. 9.5” height, 16” width, 14” depth.
Sub up/port back.

Cut sheet

2-16”x14”
2-16”x8”
2-14”x8
1-10.75”x8-port wall #1
1-2.25”x8-port wall #2

 

[1point21gigawatts]

 

[1point21gigawatts]

Cut sheet

2-16”x14”
2-16”x8”
2-14”x8
1-10.75”x8-port wall #1
1-2.25”x8-port wall #2

1-10.25”x8”-port wall #1
1-2.75”x8”-port wall #2
clerical error wasn’t my fault. Fixed. No need for any bracing or 45s.

 

[metalheadjoe 10+ year member]

Yes, but my amp will see the 2ohm load after the rise. That's my question. Your answer was a bit vague regarding amp's stability. How does impedance rise play into this?

Amp is rated down to 2. Wire subs down to 2. There is some wiggle room, but nobody on the internet will buy you new equipment, so play it safe or accept the risk.

Very few people on this site even know the difference between impedance and resistance.

 

[Doxquzme Premium Member]

Good specs, wrong design. Kudos. Hold up.
Port specs- 3”x8”, 14” port length.
Box specs. 9.5” height, 16” width, 14” depth.
Sub up/port back.

??? That box, tuned to 33hz, nothing wrong with that.

You can move the ports around if you want, but generally speaker-ing, when possible, ports are best left exiting the same baffle with the driver so the backwave of the sub couples with the front wave exiting the front. If you want to tune it lower, I get it, but that is just an example as I didn't see anything specific as to the tuning desired. 37-40, for volume reasons, 29 to 35 hz for sound quality reasons. Not a lot to hear below 35 hz and tuning to 25 while doable with that Si sub is doable, lots of wasted effort if tuning is too low.

 

[1point21gigawatts]

??? That box, tuned to 33hz, nothing wrong with that.

You can move the ports around if you want, but generally speaker-ing, when possible, ports are best left exiting the same baffle with the driver so the backwave of the sub couples with the front wave exiting the front. If you want to tune it lower, I get it, but that is just an example as I didn't see anything specific as to the tuning desired. 37-40, for volume reasons, 29 to 35 hz for sound quality reasons. Not a lot to hear below 35 hz and tuning to 25 while doable with that Si sub is doable, lots of wasted effort if tuning is too low.

 

[1point21gigawatts]

It happens. Programs are never spot on. Figuring yourself is the best way. the12volt.com is the best for calculators for figuring. On the port figuring if round, you half to add an inch if the aeros are flared. That’s it.

 

[Doxquzme Premium Member]

Sorry bud, your box is too small. Si calls or a 1.4 cu ft box. With the adderd bracing that I put in and the corners braces too, you get to around 1.4 cu ft net. that port is tuned to 33 hz which you could change if you wanted too. the measurements you provided only give you .83 cu ft net using .75" thick ,aterial.

 

[1point21gigawatts]

Sorry bud, your box is too small. Si calls or a 1.4 cu ft box. With the adderd bracing that I put in and the corners braces too, you get to around 1.4 cu ft net. that port is tuned to 33 hz which you could change if you wanted too. the measurements you provided only give you .83 cu ft net using .75" thick ,aterial.

The one I corrected for you is 1.75 cubes. The one I drew out for him is 1.5 cubes. No program can do this.

 

[Doxquzme Premium Member]

It happens. Programs are never spot on. Figuring yourself is the best way. the12volt.com is the best for calculators for figuring. On the port figuring if round, you half to add an inch if the aeros are flared. That’s it.

I already got the box volume requirements from Si. That box I provided takes into account the driver, port and brace displacements too. It's pretty spot on.