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can someone verify if this design works and is accurate?


akuma4u

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1 hour ago, akuma4u said:

ah man you are a lifesaver seriously. thank you so much!

i will get this over to my builder. what is the tuning of this box and net airspace?

Its 1.78 cu ft and should be tuned to about 37 Hz. 

"Nothing prevents people from knowing the truth more than the belief they already know it."
"Making bass is easy, making music is the hard part."

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so.. a follow up to this.. i received my reconed zv3 with zv4 parts and an spl cone.. i put it in a box im using for a sa 12 and it doesnt sound too good (but it should have as a zv3 in a sa 12 box will sound decent). I called sundown to ask and confirm if the upgraded zv3 i built upon their recommendation would work in an enclosure for a zv3 OR if it would work for an enclosure for a zv4.. the technician told me its a little of both so to use nothing less than 2 cubes.. i told him i cant really do that because i dont have the space after the port. He asked me about the design. I told him the details of the labrynth design with 39 sq in of port 1.75 cubes.. he stopped me and said its way way too much port area and that it would become a 1 note box good for competition use only and not for music. He then told me about the 12 to 16 sq in formula.. i then told him i know of it and there is a user on smd forum that has a more precise way to calculate the port area and it takes into consideration the port velocity. He told me people will always say different things and he has more experience and he said that i need to stay as close to 2 cubes net and 30 sq inches of port as possible especially since its now a zv3/zv4 and not just a zv3 which if it was i couldve gotten away with less than 2 cubes but now i cant. he said and 2cubes 30sq in of port will sound great on music and not be a 1 note wonder box.

i did explain to him that im overpowering and he still said 30 sq inches is ample and what always works out for him

im a little confused now.. on one hand your calculator suggests more port area.. on the other hand.. the 1.75 net is working against me cuz the upgraded parts have changed the enclosure requirements..

on the other hand he is saying less port area but with less port area i can now give the sub the 2 cubes it wants..

which way should i go?

 

 

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Well you already built a box that is undersized with the recommended port area on here. I would suggest go by what Sundown tells you and see what it sounds like. 

 

I'm by no means an expert but tests have shown how port area can affect output. Triticum has performed tests himself.

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On 1/8/2018 at 9:04 PM, Triticum Agricolam said:

Its 1.78 cu ft and should be tuned to about 37 Hz. 

hey .. if i reduce the port from 3.25 to 3 inches  .. what would the tuning become and the net airspace? aiming to keep the tuning around 35 hz -36hz .. pretty sure the physical port length would change.

i learned that the reconed zv3 with zv4 parts needs as close to 2 to 2.5net as possible as the sub is basically a zv4 and not a zv3 as i thought it was before..so only way to achieve this is the make the port smaller so i can increase net airspace. so i am hoping that by keeping the same labrynth design u made and just decreasing the port width to 3 inches may be able to achieve that.. i just dont know what the tuning and net airspace will become.

sub displacement is .24

aiming for 2 net  36 sq in of port area, and 35-37hz tuning

sorry for the hassles.. this is first time i re-coned using upgraded parts, i didnt know it would change everything so much .. i learned my lesson for next time.

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On 1/15/2018 at 1:59 PM, akuma4u said:

so.. a follow up to this.. i received my reconed zv3 with zv4 parts and an spl cone.. i put it in a box im using for a sa 12 and it doesnt sound too good (but it should have as a zv3 in a sa 12 box will sound decent). I called sundown to ask and confirm if the upgraded zv3 i built upon their recommendation would work in an enclosure for a zv3 OR if it would work for an enclosure for a zv4.. the technician told me its a little of both so to use nothing less than 2 cubes.. i told him i cant really do that because i dont have the space after the port. He asked me about the design. I told him the details of the labrynth design with 39 sq in of port 1.75 cubes.. he stopped me and said its way way too much port area and that it would become a 1 note box good for competition use only and not for music. He then told me about the 12 to 16 sq in formula.. i then told him i know of it and there is a user on smd forum that has a more precise way to calculate the port area and it takes into consideration the port velocity. He told me people will always say different things and he has more experience and he said that i need to stay as close to 2 cubes net and 30 sq inches of port as possible especially since its now a zv3/zv4 and not just a zv3 which if it was i couldve gotten away with less than 2 cubes but now i cant. he said and 2cubes 30sq in of port will sound great on music and not be a 1 note wonder box.

i did explain to him that im overpowering and he still said 30 sq inches is ample and what always works out for him

im a little confused now.. on one hand your calculator suggests more port area.. on the other hand.. the 1.75 net is working against me cuz the upgraded parts have changed the enclosure requirements..

on the other hand he is saying less port area but with less port area i can now give the sub the 2 cubes it wants..

which way should i go?

 

 

Unfortunately just because someone works for a sub manufacturer doesn't guarantee they know what they are talking about.  I don't know who you talked to, but I'm going to disagree with them and here is why.  First off the numbers that person gave you aren't consistent with other information Sundown has put out.  They recommend 32 sq in for Zv3 on rated power and 40 sq in for Zv4s.  If you sub is more like a Zv4 now it would be reasonable to assume it should be closer to 40 sq in, and that assuming rated power.  You are exceeding rated power so that should further increase your port area.  

The second reason I think that guy is wrong is he pulled out the "I have more experience" line.  The fact is he has absolutely no idea how much experience the other person giving you advice has and to just arbitrarily claim he knows more is pompous and is generally used by people who can't back up their "knowledge" with any kind of measurable data.  In case its not obvious, it drives me nuts when people blindly make the "I have more experience" claim.  He may very well have a lot more experience than I do and most people in general, but that alone doesn't make him right.   

The fact that the guy talks about how high port area makes for a one-note-wonder and he recommends you use the 12-16 sq in formula indicates to me that he is just regurgitating the normal car audio design myths that I have proven to often be incorrect.  Ok, I'm getting off my soapbox now.  

 

On 1/22/2018 at 9:32 AM, akuma4u said:

hey .. if i reduce the port from 3.25 to 3 inches  .. what would the tuning become and the net airspace? aiming to keep the tuning around 35 hz -36hz .. pretty sure the physical port length would change.

i learned that the reconed zv3 with zv4 parts needs as close to 2 to 2.5net as possible as the sub is basically a zv4 and not a zv3 as i thought it was before..so only way to achieve this is the make the port smaller so i can increase net airspace. so i am hoping that by keeping the same labrynth design u made and just decreasing the port width to 3 inches may be able to achieve that.. i just dont know what the tuning and net airspace will become.

sub displacement is .24

aiming for 2 net  36 sq in of port area, and 35-37hz tuning

sorry for the hassles.. this is first time i re-coned using upgraded parts, i didnt know it would change everything so much .. i learned my lesson for next time.

So if you reduced the port width from 3.25" to 3" it will increase your net volume by about .05 cu ft and decrease your tuning by about 1.5 Hz.  

My personal opinion is that's not enough of an increase in net volume to be worth it.  Furthermore, increasing net volume without a corresponding increase in port area to support it is going to be counterproductive.  Really though the change is pretty small so its probably not going to make much difference in performance either way.  

"Nothing prevents people from knowing the truth more than the belief they already know it."
"Making bass is easy, making music is the hard part."

Builds:

U7qkMTL.jpg  LgPgE9w.jpg  Od2G3u1.jpg  xMyLoO1.jpg  9pAlXUK.jpg

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48 minutes ago, Triticum Agricolam said:

Unfortunately just because someone works for a sub manufacturer doesn't guarantee they know what they are talking about.  I don't know who you talked to, but I'm going to disagree with them and here is why.  First off the numbers that person gave you aren't consistent with other information Sundown has put out.  They recommend 32 sq in for Zv3 on rated power and 40 sq in for Zv4s.  If you sub is more like a Zv4 now it would be reasonable to assume it should be closer to 40 sq in, and that assuming rated power.  You are exceeding rated power so that should further increase your port area.  

The second reason I think that guy is wrong is he pulled out the "I have more experience" line.  The fact is he has absolutely no idea how much experience the other person giving you advice has and to just arbitrarily claim he knows more is pompous and is generally used by people who can't back up their "knowledge" with any kind of measurable data.  In case its not obvious, it drives me nuts when people blindly make the "I have more experience" claim.  He may very well have a lot more experience than I do and most people in general, but that alone doesn't make him right.   

The fact that the guy talks about how high port area makes for a one-note-wonder and he recommends you use the 12-16 sq in formula indicates to me that he is just regurgitating the normal car audio design myths that I have proven to often be incorrect.  Ok, I'm getting off my soapbox now.  

 

So if you reduced the port width from 3.25" to 3" it will increase your net volume by about .05 cu ft and decrease your tuning by about 1.5 Hz.  

My personal opinion is that's not enough of an increase in net volume to be worth it.  Furthermore, increasing net volume without a corresponding increase in port area to support it is going to be counterproductive.  Really though the change is pretty small so its probably not going to make much difference in performance either way.  

Thanks for helping me out again -

regarding the advice i received.. im a little upset for a couple of reasons with the techs i spoke to at sundown. 1st) when i called for recone parts (i had a damaged foam roll and needed it fixed) the tech i spoke to who is their main tech i wont mention his name tho , he built up a list of upgraded parts that consisted of a zv4, x series and i think even zv5.. he said it would give a warmer sound and sound better but instead of the mage roll he would give me the spl surround cone/roll.. so i asked him if i would need a new box,. he said no i can use the same box i had. THIS is very important because my trunk is small and i can only fit less than 2 cube net boxes in there... and zv3 12 stock version works in those small types of boxes. Anyways he said it would work and i paid and it was a lot of money for shipping close to 200 alone! for such a small lightweight package..

so i get the parts recone it and then i find out the depth has increased almost by 3 inches which now im forced to build a new box.. so then i make this thread and get the design and i didnt know about the depth so then that build went to garbage and i got u to redesign then just before i am about to build it the recone guy tells me that 1.75net is too small i basically have a zv4 now.. so this makes me call sundown again and i get connected to a different tech and he asks me why would i change all the parts and who told me to do that, and i told him the head tech did and he said thats not what he would have done and the sound will change too much and i dont have a zv3 anymore.. so i told him i just followed what he told me. Then he also said the box needs to be bigger. then i tried fooling around to get a bigger box.. which i am trying to do now.. but not sure if it can be done..

i called sundown again and asked to speak to the first main tech who made the order and told him the issues and he now says yes i need a bigger box, i told him he said differently before and he said he was mistaken.. i told him im too far into this and spent too much money already and im possibly screwed now.. he didnt offer anything and told me that i can do 2 net and 30 sq in of port. i told him then about port area not being enough and all that and he told me eveyrone will say something different and he has tried many boxes and if i do 36 or more sq inch of port it will be 1 note box etc... then he hit me with the 12-16 per cube thing and i told him that is too general.. anyways call ended with him telling me to do the 2 cube 30 sq in box..

so that was my experience.. not happy really.. i wish i knew from the start i would require a bigger box and my sub would basically become a zv4.. if i knew that then i would have demanded straight zv3 parts to keep it a zv3 as i wouldnt run into any box size issues plus i like the sound of this sub stock..

now.. as the box design is concerned now.. i am surprised decreasing the port .25 inches would only increase .05net in airspace.. thasts like nothing..

so i guess i should just stick to the original design u made of 1.75net and 39 sq in of port ?  i do have to add yes the zv4 requires 40 sq in of port but thats with a stock zv4 with the mega roll surround.. with mine im using a spl surround and it doesnt require as much port area.. this is exactly what the head tech told me when i asked him and brought up the 40 sq in of port area on a zv4..

what design would you do if u were in my position? if its the same design u made up top a few posts ago, i will just go ahead with that one.

note: funny thing is.. i have a single sa 12 that is in a box that the head tech told me to build, which i had built for the zv3 i bought months ago (he told me to make a 1.85 27sqin box for the zv3 12 when i made the order from them).. it sounded MEH on the zv3.. but once i replaced it with the sa12 (box now becomes around 1.95-2net 27 sq in of port) WOW. sa 12 in that box sounds so much better.. even better than the zv3 did and thats on HALF the rms as well. I guess because the sa12 is better suited in this box than the zv3 was. i guess this goes to show how important a proper box is.

thanks again for spending the time helping me.

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1 hour ago, mathewyocham said:

You could assemble the box in your trunk maybe?

the problem with my trunk is 2 things. 1) the trunk opening or the mouth is so small its hard to get a large piece of wood.. this is the reason only small boxes can fit inside with a max height of 13-13.5 inches 2) its a bass trap style trunk where there is a very little port from trunk to cabin so a lot of bass gets stuck inside the trunk and doesnt freely flow into the cabin.

i did find a guy that was willing to do a trunk build but then when he inspected my trunk he backed out LOL

i may end up selling this sub  and take a HUGE loss.. i dont even know if its worthwhile to build the enclosure for this sub do to my limitations.. i will see if sundown can send me regular zv3 recone parts for a considerable discount then i will just recone it again back to stock and THEN i can run a proper box. Or i may just wait for the new U series OR i may just go 2 12s sealed.. i know boxes for those will work with the exception of the U 12 cuz the specs hasnt been released for those yet but im sure it will work.

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Yeah @akuma4u, I'd be pretty frustrated if I were you.  

If I were in your shoes, I'd build the labyrinth design I first gave you, I feel it's the least compromised based on the space constraints you have to work within.  However, I would try to find someone that can build it for the least amount of money and still do a good job.  I wouldn't bother having them paint it or do any finish work, just basic assembly so you have as little money in to it as possible, and then see how it sounds in your car.  If you like it then you can pull it back out and have the finish work done, if you don't like it you can probably sell it to recoup some of you cost and then you can decide where to go from there should the need arise.  

"Nothing prevents people from knowing the truth more than the belief they already know it."
"Making bass is easy, making music is the hard part."

Builds:

U7qkMTL.jpg  LgPgE9w.jpg  Od2G3u1.jpg  xMyLoO1.jpg  9pAlXUK.jpg

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