Hi all...
Would really appreciate any comments/help I could get...
Need help with a enclosure build I've just done...
So... I had the Orion HCCA 12.2 in a 1.6cuft after displacement tuned to 40/41hz, with about 29sq inches of port running of a Soundstream TX2600.1 @1ohms giving around 2000w...
It obviously lacked low extension Which I Really WANT!!!
So I made a box just over 3cuft after displacement and bracing tuned it to 30 Hz with 43.75 port area, giving around 14sq inches per cube...
Now the first box sounded good with a lot,a lot of SPL at around tuned frequency really hitting hard (midbass).
The box that I built, (won't let me attach pics) low bass sounds really hollow, and at times sounds if the sub is bottoming out... Not playing below tuned frequency. It drops well but lacks the deepness in sound and have lost upper bass noticeably which is accepted tuning at lower freq. But still plays mid bass well...
So after reading some threads I polyfilled the box adding polyfill roll to the inside walls keeping well clear of the port...
Result: It killed of the output, I would say about 15 to 20% @ lower freq...
I used 3/4 inch MDF as that is the thickest I could get from the local DIY but well braced...
Now I believe the Only thing causing this MUST be the port area which I should have gone by around 9 sq inches per cube!!! But according to Winisd the air velocity rocketed resulting in port noise...
SO WHERE HAVE I GONE WRONG.....HELP!!!
THANKS*
Would really appreciate any comments/help I could get...
Need help with a enclosure build I've just done...
So... I had the Orion HCCA 12.2 in a 1.6cuft after displacement tuned to 40/41hz, with about 29sq inches of port running of a Soundstream TX2600.1 @1ohms giving around 2000w...
It obviously lacked low extension Which I Really WANT!!!
So I made a box just over 3cuft after displacement and bracing tuned it to 30 Hz with 43.75 port area, giving around 14sq inches per cube...
Now the first box sounded good with a lot,a lot of SPL at around tuned frequency really hitting hard (midbass).
The box that I built, (won't let me attach pics) low bass sounds really hollow, and at times sounds if the sub is bottoming out... Not playing below tuned frequency. It drops well but lacks the deepness in sound and have lost upper bass noticeably which is accepted tuning at lower freq. But still plays mid bass well...
So after reading some threads I polyfilled the box adding polyfill roll to the inside walls keeping well clear of the port...
Result: It killed of the output, I would say about 15 to 20% @ lower freq...
I used 3/4 inch MDF as that is the thickest I could get from the local DIY but well braced...
Now I believe the Only thing causing this MUST be the port area which I should have gone by around 9 sq inches per cube!!! But according to Winisd the air velocity rocketed resulting in port noise...
SO WHERE HAVE I GONE WRONG.....HELP!!!
THANKS*
Cheers mate...
I have downloaded a few pics but they not displaying for some reason...
The port is 12.5 x 3.5 inches and 38 inch long, which tunes at 30hz...
Port area is 43.75 sq in. Giving about 14 sq in per cubic...
I mentioned air velocity about having around 9 sq inches per cube which is going to make it sky high...
I have downloaded a few pics but they not displaying for some reason...
The port is 12.5 x 3.5 inches and 38 inch long, which tunes at 30hz...
Port area is 43.75 sq in. Giving about 14 sq in per cubic...
I mentioned air velocity about having around 9 sq inches per cube which is going to make it sky high...
ok ... From WINISD your simulated box what is the peak air velocity? I suggest that the port Velocity to stay below 13ms to prevent chuffing and compression issues. If possible try to go for larger port (5inches) as chances you will get lower chuffing with larger diameter ports ... My subs were using 4inch port and still there is port noise ...
The fact that in order for a subwoofer to perform well, the lower you go you will actually need more port area as the compression and chuffing is much more audible and noticeable on lower frequencies. Therefore it will starts to call for Larger diameter and Longer Ports for subwoofers that tuned low.
There is a nice website i linked below regarding all the information you need for building a subwoofer box ... hope it helps
Collo's DIY Subwoofer Enclosures
There is a nice website i linked below regarding all the information you need for building a subwoofer box ... hope it helps
Collo's DIY Subwoofer Enclosures
So here are a couple things to think about.
At 3 cu ft net, your enclosure is way too big. On over 2000 watts Orion recommends a 1.5 cu ft enclosure, you can probably get away with a little bigger than that, but no too much. As you make a ported enclosure larger cone excursion increases and at some point you can damage your sub. Output around tuning also increases with enclosure size and you will end up with really peaky output as well.
Forget everything you have heard about "port area per cube". That guideline doesn't factor in how much input power you will be running or what frequency you are tuned to. It will give you a wrong answer just as often as it will give you a correct one. You already have the right tool for port sizing, WinISD. Based on your 2600 watts of input power you want to keep your port velocity low. Just how low is a matter of opinion. I try to keep it in the 22-24 m/sec range for car audio subwoofers. You can often get away with as high as 30 m/sec, but you will lose some output to port compression.
At 3 cu ft net, your enclosure is way too big. On over 2000 watts Orion recommends a 1.5 cu ft enclosure, you can probably get away with a little bigger than that, but no too much. As you make a ported enclosure larger cone excursion increases and at some point you can damage your sub. Output around tuning also increases with enclosure size and you will end up with really peaky output as well.
Forget everything you have heard about "port area per cube". That guideline doesn't factor in how much input power you will be running or what frequency you are tuned to. It will give you a wrong answer just as often as it will give you a correct one. You already have the right tool for port sizing, WinISD. Based on your 2600 watts of input power you want to keep your port velocity low. Just how low is a matter of opinion. I try to keep it in the 22-24 m/sec range for car audio subwoofers. You can often get away with as high as 30 m/sec, but you will lose some output to port compression.
Is it possible for you to check this out as I may be mistaken...
Would really really appreciate it...
Orion HCCA 12.2 black version...
Box is 3.1ish cuft after all displacement...
12.5x3.5 inches port opening and 38 inches long...
And IF it is the box (port) what would you recommend...
Thanks...
Would really really appreciate it...
Orion HCCA 12.2 black version...
Box is 3.1ish cuft after all displacement...
12.5x3.5 inches port opening and 38 inches long...
And IF it is the box (port) what would you recommend...
Thanks...
With those specs your peak port velocity is still around 34 m/sec, which is high enough its costing you output.
The difficult part about these high power car audio subwoofer enclosures is getting enough port area to keep port velocities reasonable, while keeping tuning where you want it, without the port being so long you have pipe resonance issues (which is what you get if the port is much over 40" long).
Another issue is if your port is a 3 common wall slot port, WinISD doesn't properly calculate end correction for that style of port, so you are probably tuned lower than you intend. With the dimensions you gave you are probably tuned closer to 28 Hz or so.
For the size of box and amount of power you are running you are probably going to want more like 50-55 sq in of port area. If you give me the max dimensions of the space you have to work with I can probably come up with a design for you.
Hi abbss1
I think your box tuning is off. According to the thiele/small parameters, a 1.6cuft tuned to 40Hz looks like the first plot.
For the same volume (1.6cuft), I would tune to 25Hz (second plot).
The optimum volume is 0.86cuft. tuned to 28Hz (RED PLOT).
This is for home use. If you're using it in a car, then the tuning is different.
Hope it helps.
I think your box tuning is off. According to the thiele/small parameters, a 1.6cuft tuned to 40Hz looks like the first plot.
For the same volume (1.6cuft), I would tune to 25Hz (second plot).
The optimum volume is 0.86cuft. tuned to 28Hz (RED PLOT).
This is for home use. If you're using it in a car, then the tuning is different.
Hope it helps.
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Thanks so much thejessman
I've been messing around with ALL my settings...
Regrounded the earth and so on...
Checking all wiring and connections...
For the last week or so lol...
Ok I will be using 3/4 inch MDF as that's all I can get from local DIY...
Max height is 14 inches...
Max length is 36 inches...
And depth is 18/19 inches...
I'm after deep bass if that makes sense lol...
I've been messing around with ALL my settings...
Regrounded the earth and so on...
Checking all wiring and connections...
For the last week or so lol...
Ok I will be using 3/4 inch MDF as that's all I can get from local DIY...
Max height is 14 inches...
Max length is 36 inches...
And depth is 18/19 inches...
I'm after deep bass if that makes sense lol...
For car use, you'll need to tune to something like this. With cabin gain, The low bass on the left of the peak will increase to almost the same level as the peak.
In the first plot, the box volume is 0.53cuft (15 liters) tuned to 45Hz. This is very small for a 12". Obviously, you'll need to tune it with a slot instead of a round tube.
You can also use a slightly larger box of 0.88cuft (25 L). This will be easier to work with. Tuning is 40Hz. The problem with a larger box is the loss of mid-bass.
Ideally, the box volume should be 0.424cuft. This is very small, 10 liters. Tuned to 45Hz, the peak centers at about 70Hz. You'll be able to hear the bass notes with good bass extension.
In the first plot, the box volume is 0.53cuft (15 liters) tuned to 45Hz. This is very small for a 12". Obviously, you'll need to tune it with a slot instead of a round tube.
You can also use a slightly larger box of 0.88cuft (25 L). This will be easier to work with. Tuning is 40Hz. The problem with a larger box is the loss of mid-bass.
Ideally, the box volume should be 0.424cuft. This is very small, 10 liters. Tuned to 45Hz, the peak centers at about 70Hz. You'll be able to hear the bass notes with good bass extension.
Attachments
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