1point21gigawatts Posted June 14, 2020 Report Share Posted June 14, 2020 2 hours ago, Triticum Agricolam said: Holy hell you guys, I go to bed and wake up to three pages of back and forth between you two. 1point21gigawatts, the reason my port calculator didn't work well with the OP 2,000 watt system is because he was putting that 2000 watts into a 1.75 cu ft box. Its the relationship between power and enclosure size that matters. 2,000 watts may not sounds like a lot, but 2000 watts into a 1.75 cu ft enclosure is over a 1,000 watts per cube, and that's the point where things get very difficult. Its not the calculators fault, its the physics. Plug that amount of power into any box simulation software of your choice and try to get the port velocity below 30 m/sec and see what you get. You will find its just a very difficult problem to solve. As far as that making may calculator "useless", is a 9/16" end wrench useless because it can't tighten a 3/4" bolt? Is a hammer useless because you can't remove a screw with it? No, just about everything on this planet is designed for a specific job and to work within a given set of parameters, I made it very clear on my calculator when you went outside the parameters that it is designed to work within. It seems to me like you are really looking for something to prove here and you WANT to find flaws in my calculator so you can discredit it instead of just accepting it for what it is. I'm going to get on my soapbox for a minute, it's a bit unfortunate that amp power has gotten so cheap these days. The reason I say that is that it makes it easy for people to attempt things that are going to be very difficult to get to work well. Systems with more than 1,000 watts per cube are what I'm talking about. Once you get to that level of power you are well into the point of diminished returns and mostly what you are doing is wasting a lot of money IMHO (certain competition systems are the exception to this, but those people know who they are). I've never done this particular test, but I bet if you had a 2,000 watt per cube system, you optimized it as much as you could and then put it on an amp half the size (or turned the gain down), so 1000 watts per cube, in most cases you wouldn't even lose 1 db of output. Nobody wants to think about this though since they spent all that money on the big amp and all the power upgrades to support it. As far as the end correction stuff goes, I do have my own way of determining it. I've found the usual method of adding half the port width to give inconsistent results. If you want to talk about end correction please PM me or start a new thread so we don't further clutter up akuma4u's thread. That’s what I was kinda thinking that it wasn’t calculating correctly because the enclosure was too small. I told him to make the enclosure bigger but he said a sundown tech told him that 1.75 cubic foot would be the way to go on the subwoofers he wanted to run in that enclosure. And I never wanted to discredit you or hate on you or anything like that when it comes to your formulas or that port area calculator. I was just let down so hard about that calculator because I had followed your posts and work for so long and to be let down like that was a big deal so I lashed out because to me, I believe your calculator should work on any subwoofer enclosure, no matter the size or rms rating. That’s just what I expected out of it. But I understand and I guess I was looking at the whole ordeal in the wrong way. Because a calculator is there to reference for help, not do the job for you and nothing but God can be perfect. Then to see something foreign when it come to end correction made me question even more. You have to understand, because for years I would follow your work and I would say to myself, “that dude has got to be one of the best subwoofers enclosure guys that’s ever been.” So seeing what appears to be flaw or something out of the norm from your end when it comes to subwoofer enclosures was not something that sit well with me. Then I didn’t see you post new things in a long time and that was a bummer too. I was wrong for that. So I do apologize and hope we can clear things up and move past this. “How can we help you?” “And don’t forget to tell them that the customer isn’t always right.” Link to comment Share on other sites More sharing options...
akuma4u Posted June 14, 2020 Author Report Share Posted June 14, 2020 1 hour ago, Triticum Agricolam said: Holy hell you guys, I go to bed and wake up to three pages of back and forth between you two. 1point21gigawatts, the reason my port calculator didn't work well with the OP 2,000 watt system is because he was putting that 2000 watts into a 1.75 cu ft box. Its the relationship between power and enclosure size that matters. 2,000 watts may not sounds like a lot, but 2000 watts into a 1.75 cu ft enclosure is over a 1,000 watts per cube, and that's the point where things get very difficult. Its not the calculators fault, its the physics. Plug that amount of power into any box simulation software of your choice and try to get the port velocity below 30 m/sec and see what you get. You will find its just a very difficult problem to solve. As far as that making may calculator "useless", is a 9/16" end wrench useless because it can't tighten a 3/4" bolt? Is a hammer useless because you can't remove a screw with it? No, just about everything on this planet is designed for a specific job and to work within a given set of parameters, I made it very clear on my calculator when you went outside the parameters that it is designed to work within. It seems to me like you are really looking for something to prove here and you WANT to find flaws in my calculator so you can discredit it instead of just accepting it for what it is. I'm going to get on my soapbox for a minute, it's a bit unfortunate that amp power has gotten so cheap these days. The reason I say that is that it makes it easy for people to attempt things that are going to be very difficult to get to work well. Systems with more than 1,000 watts per cube are what I'm talking about. Once you get to that level of power you are well into the point of diminished returns and mostly what you are doing is wasting a lot of money IMHO (certain competition systems are the exception to this, but those people know who they are). I've never done this particular test, but I bet if you had a 2,000 watt per cube system, you optimized it as much as you could and then put it on an amp half the size (or turned the gain down), so 1000 watts per cube, in most cases you wouldn't even lose 1 db of output. Nobody wants to think about this though since they spent all that money on the big amp and all the power upgrades to support it. As far as the end correction stuff goes, I do have my own way of determining it. I've found the usual method of adding half the port width to give inconsistent results. If you want to talk about end correction please PM me or start a new thread so we don't further clutter up akuma4u's thread. I needed a new amp and i got an incredible deal on a wolfram c2400 and the amp is legit. So i got it. It had plenty of power for my current subs and for later builds and did i mention i got it at a great price? So to me it is not money wasted. Power wasted? For now on my 2 cube box...yes as i barely have the amo gain turned up. Hence why i was told to go to a smaller 1.75 box so i can put more power to it and also get more output. So when i tried to design a box using your calculator the port length was like 40 inches or so and i ran out of room. This was with the widest port i could fit in. I have no choice but to reduce the port width so i can fit in a port that ends leaving 2x the port width between the end of port wall and box side wall. I believe this is what you suggested right? So looks like its gonna be 1.75net with a 2.5 to 3 inch wide port tuned to about 36 or 37hz.. if anyone can do a design that would be great.. my max outer dimensions are 13.5 high x 32 wide x 17 deep. Need a double baffle and some 45 pieces in corners. This is for a single 12 sundown u12 d2 running at 1 ohm 2000rms Thanks in advance for anyone who can do a design! Link to comment Share on other sites More sharing options...
akuma4u Posted June 14, 2020 Author Report Share Posted June 14, 2020 Sorry just wanted to add..ive heard this so often..that if you are overpowering a sub which in my case i am. My sub is rated for 1500rms and im giving it 2k or 2k+, that you should make the box smaller. So if i make the box bigger like suggested by 1.21gigawatts , that would bottom the sub out easily no? Over excursion? Link to comment Share on other sites More sharing options...
1point21gigawatts Posted June 14, 2020 Report Share Posted June 14, 2020 9 minutes ago, akuma4u said: Sorry just wanted to add..ive heard this so often..that if you are overpowering a sub which in my case i am. My sub is rated for 1500rms and im giving it 2k or 2k+, that you should make the box smaller. So if i make the box bigger like suggested by 1.21gigawatts , that would bottom the sub out easily no? Over excursion? No. It’s not like that increase is too big and you don’t have it tuned too low. So don’t worry about that. And you’re not overpowering that subwoofer. Don’t sleep on sundown and plus don’t forget to factor in impedance rise and voltage drop. That amp is nice for that subwoofer, it could handle a little more too. So you’re good. Make the enclosure bigger. No worries. “How can we help you?” “And don’t forget to tell them that the customer isn’t always right.” Link to comment Share on other sites More sharing options...
akuma4u Posted June 14, 2020 Author Report Share Posted June 14, 2020 5 minutes ago, 1point21gigawatts said: No. As long as you don’t make that subwoofer enclosure like super crazy big. Don’t worry about that dude. And you’re not overpowering that subwoofer. Don’t sleep on sundown and plus don’t forget to factor in impedance rise and voltage drop. That amp is nice for that subwoofer, it could handle a little more too. So you’re good. Make the enclosure bigger. Any chance u can model 2.20net at 36 to 38hz vs 1.75 at 36 to 38hz off 2krms just so i can see the response and have more insight? Link to comment Share on other sites More sharing options...
1point21gigawatts Posted June 14, 2020 Report Share Posted June 14, 2020 6 minutes ago, akuma4u said: Any chance u can model 2.20net at 36 to 38hz vs 1.75 at 36 to 38hz off 2krms just so i can see the response and have more insight? That’s 10% bigger than recommended, that would work good. Most of the time I design enclosures that are 10-20% bigger in volume and port area and tweak the tuning to compensate. It works out better than recommended. You don’t want to go with that 1.75 cubic foot enclosure. “How can we help you?” “And don’t forget to tell them that the customer isn’t always right.” Link to comment Share on other sites More sharing options...
akuma4u Posted June 14, 2020 Author Report Share Posted June 14, 2020 10 minutes ago, 1point21gigawatts said: That’s 10% bigger than recommended, that would work good. Most of the time I design enclosures that are 10-20% bigger in volume and port area and tweak the tuning to compensate. It works out better than recommended. You don’t want to go with that 1.75 cubic foot enclosure. According to sundown, the u sub and the zv3 sub must be used in small enclosure it actually says this on the zv3 12 product page on their site. They also said the u series sub takes the exact same box as the sa12...to my knowledge people usually do 1.75 to 2 cubes on an sa12..never seen anyone go bigger. I did find a few posts about using more than 2 cubes on a zv3 12 and he said he hit the backplate easily on low power when he went up to 2.25net so he suggested what the owner of sundown suggested .. 1.5 to 2 cubes with 1.75 and below being what he prefers. Plus the tech at sundown told me to go 1.75 at 36hz. So u see why im so hesitant to go bigger than 2net..not saying it wont work but...just hesitant.... Also if i go ahead and do it and rip 2k on a oversized box im worried i may damage the sub by over excursion or bottoming it out rapidly and easily.. Sorry for being so hesitant but tryin to be safe.. Link to comment Share on other sites More sharing options...
akuma4u Posted June 14, 2020 Author Report Share Posted June 14, 2020 ok im fooling around with a torres design using a 2.15 to 2.20 met size box and it can be done BUT,. my port area wont even hit triticums minimum port area value.. 42 to 44 sq inches is what it calls for minimum and im getting 36 to 39... Link to comment Share on other sites More sharing options...
1point21gigawatts Posted June 14, 2020 Report Share Posted June 14, 2020 25 minutes ago, akuma4u said: According to sundown, the u sub and the zv3 sub must be used in small enclosure it actually says this on the zv3 12 product page on their site. They also said the u series sub takes the exact same box as the sa12...to my knowledge people usually do 1.75 to 2 cubes on an sa12..never seen anyone go bigger. I did find a few posts about using more than 2 cubes on a zv3 12 and he said he hit the backplate easily on low power when he went up to 2.25net so he suggested what the owner of sundown suggested .. 1.5 to 2 cubes with 1.75 and below being what he prefers. Plus the tech at sundown told me to go 1.75 at 36hz. So u see why im so hesitant to go bigger than 2net..not saying it wont work but...just hesitant.... Also if i go ahead and do it and rip 2k on a oversized box im worried i may damage the sub by over excursion or bottoming it out rapidly and easily.. Sorry for being so hesitant but tryin to be safe.. The sundown u subwoofer and the zv3 are about the same subwoofer. Not like the sa series, not the same enclosure recommendations. The sa call for 1.75 cubic feet and the u series calls for 2 cubic feet and on each of the subwoofers I would go a little bigger than recommended. That 2.2 cubic foot design isn’t too big. Sundown allows for up to a 25% increase. You can do so on more rms than rated too because of impedance rise and plus sundown subwoofers can handle more than than rated even after rise. That tech is just a tech and they are not a designer. They never recommend over manufacturing recommendations for warranty reasons. They are just techs. You see what yielded from that port area calculator when you used such a small enclosure on that much rms. Plus when I ran the numbers, it didn’t yield well. So 2-2.5 cubic feet would be the best bet and that’s what was yielding well. And now look at the sundown u series 12” subwoofer recommendations and the brief description. “How can we help you?” “And don’t forget to tell them that the customer isn’t always right.” Link to comment Share on other sites More sharing options...
1point21gigawatts Posted June 14, 2020 Report Share Posted June 14, 2020 7 minutes ago, akuma4u said: ok im fooling around with a torres design using a 2.15 to 2.20 met size box and it can be done BUT,. my port area wont even hit triticums minimum port area value.. 42 to 44 sq inches is what it calls for minimum and im getting 36 to 39... 36 to 39 would work. 39 would be ideal because the increase of recommended volume is about 10% and 39 is about 10% increase in recommended port area. That would work ideally. “How can we help you?” “And don’t forget to tell them that the customer isn’t always right.” Link to comment Share on other sites More sharing options...
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