ncc74656

how long does it take to machine a sub from the time the CNC starts? i assume blocks of aluminum are ordered and the machine is right there to accept them and bore/lath them out? once the hard parts are built it takes time to glue it all together but from what ive seen thats only a 20 min processes or is it more work that what is done in a recone? does every sub go through any kind of test period such as X amount of time on X hz to test for mechanical failure? im not really sure i even know how a sub magnet is assembled. does anyone have a video of any sub being built from total scratch? id assume the processes is similar weather its a Fi, Kicker, SSA, explode, ect.

i am no box builder but i thew this together in my spare time. does it meet your needs? http://imgur.com/a/j00Gx

i ordered a SP4 on the 11th, it went into awaiting fulfillment on the 16th. order number: 1918. god i want to get that sub!!!! i sold my BL 5 days before i ordered this SP4 so ive been using my computers sub on my ZX2500.1 - a tiny vidsonix 15" i bought back in 2002. when i bought my BL it took 3 months to arrive... i really hope i get the SP4 this week

so the N series subs are gone due to the cost of neo magnets. what are we loosing as consumers? does a neo magnet make a noticeable difference when used in a comparable sub?

ill add a couple more braces to the sides of the port and call it a day. i am thinking of creating slots to hold the port in the walls. i ordered my sub on the 11th and was told 20 days to completion so im eager to receive a shipped email.

I own a BL and am buying an SP4. will this box design work perfectly for the SP4 and well enough for the BL? did i screw up on anything? at the bottom of my port i have bracing crossing it, will this be an issue? should the port be fully open down to the bottom of the box? i could not find any great info on port area for the SP4 so im sitting a bit over the 16 multiplier right now. i was thinking of adding a bit of that fluff to the box to make the sub feel it was in an enclosure closer to 8 cubic; is this a good idea? im going for SQ at high volume, or at least as much SQ as the SP4 can give me. what should i change, all opinions welcome. thank you. http://imgur.com/a/JJ7XV#0 ^ box design and maths most people seem to ask about electric so ill throw it out there. i run a factory alternator with factory battery banks. all 00ga connections between my 2 2600ca semi batteries, 4ga grounds to body and 0 ga to frame and block. the factory alternator puts out 230A @ 2100RPM. currently i have no issue with the ZX1500.1 but dont now what to expect with a BC3500@.5 ohm, guess ill find out.

1" rod i have factored in the sub mount depth

here is a build that i think is my final for my SP4 18" at a 33hz tuning and using single walled 3/4" MDF with a double baffle i dont think i need any more bracing, do i?

so when you add more than one woffer to a box you need to increase the size of the box itself for cubic feet but not the port area? so a sub that needs 5 cubic feet, when putting 2 i a box they would need 10 cubic? but they both would use the same port area for single or dual right? assuming they are sharing a single port. is that right?

im not sure you have the space for a dual setup. a single 18 recommends 7 cubic so you would need 14 with 2. there is room for a sealed enclosure... i dont have any ideas for that space. is there any more room where ever you are trying to fit it? i did a little research into dual subs when i ordered mine. my numbers came to a 31X37X31 box to come just shy of 14 cubic with an octo port.

by that definition it makes me think the SP4 will have more response than the BL i had. id be very surprised if that were the case considering the power difference.

I own a 18" BL fully loaded on a kicker ZX1500.1. this has done me well as a DD setup for a year but now i want more. I am looking for more low end and more volume with out sacrificing much of my high end. my box is currently tuned at 44hz @ 5.4 cubic feet and i was planing to build a new box tuned to 35hz @ 7.99 cubic feet. i have the option to swap my 1500.1 with a 2500.1 plus a couple hundred and stick that behind the BL. would i blow it with this setup assuming im not an idiot with gains and the bass blow knob? my second thought was to sell my sub and box to buy a SP4 and stick that on a BC3500.1D crachendo amp. i read that this amp can run .5 stable where as my kicker prefers to sit 1.5-2ohm. my understanding of things is if i change my parallel/series wiring on my current dual 1ohm sub that it will run at .35ohm as each coil is .7. would i blow something up running a SP4 with a BC amp at such an ohm rating? I am currently satisfied with the frequency response of my BL with the exception of low end, which i acknowledge is a box design issue rather than a sub spec issue. i am unsure what route to choose. will the SP4 match the BL in sq? will the kicker be to much or to little for the BL, will the BC melt at .35ohm, am i not understanding anything correctly? The box i was planing to build is .75mdf with a coat of resin and rounded edges. i assume other than changing some bracing for mount depth that a BL and SP4 could run in the same box? this is what i was planing on building: http://imgur.com/a/coFsq

yea ive stepped back on the redesign. i am considering an octo port tho, not sure how that would work out.

id be curious to know how many SP4's Fi has sold. the ratio of fires to sold product would be a pretty clear and definitive answer to the debate. i get my SP4 perhaps late this month and its going on a ZX2500.1, i think im going to buy a fire extinguisher just in case tho

hell i dont know anymore. that was an old enclosure design i had built up months ago with the help of the12volt.com and SMD forums. im so far from that design now tho... im looking at 7 cubed, 118 squared port area, 33hz tune, 31.5X3.75 slot port. i have a guy who is telling me to go octo port so i might have one more box redesign in my future.

is that enough bracing or should i add more? if i need more what kind should i use?

i just ordered my SP4 18 today, i thought i had a box idea but i was told it was not very good so i need some help. back seat of a dodge ram 2500, i have 30HX36WX31D max space, smaller is better but thats what i have to work with. i intend to mount it on a new tool box im installing in place of the rear seat. if i use 2 .75" MDF sheets to make 1.5" panels and build the entire box of that do i need to double up on baffle? do i need bracing? i currently have a ZX2500.1 to power it (do you think i should upgrade?). i am not sure exactly where to tune it so i planned on starting with a high tune and an extra thick bottom and then extending the port and pulling parts of hte extra bottom panel out to keep the cubic footage the same while tuning. sweeping from 32-34hz is what i was going to try. what are your thoughts? here is a picture and tores of what i think i should have for optimal. i listen to lots of techno, rock, trance, kinda all over the board and i want to be able to kill the lows while still destroying hte highs. i seriously do not want any dead spots. im upgrading from a BL 18 that was just not loud enough. what should i change? thanks. http://imgur.com/a/rl7BU#1

here is my latest build. i believe i have the correct port area, cubic footage, and port size. is anything wrong or incorrect in my box? do i need more bracing? as it stands i will not need to bend my port. http://imgur.com/a/P6goi <---- 3d model

in torres i have a box of 26HX30WX26D port of 28.5W x 3.5H. when i input 21.75 as port length it tells me the physical port is 20.25", i do not understand this. the port from front of box to rear of box (leaving port height to rear of box) is 21.75" so why then does it say the physical piece of wood is 20.25" long? does some of the physical port get subtracted in some kind of equation? if i then change from 21.75 length to 22.75 the stats change to 17.75" physical port length? how can i add wood and yet have a shorter piece of wood?

what is a speed of air that is going to make port noise? ive heard that you want to keep a 9:1 ratio or below on hight X width of port. is that a hard set guide for port noise? will 25m/s air flow give me any different volume or sound quality than 20m/s assuming port noise is equal between the two? how does rounding off the port edges effect things? how much faster can the air flow with a rounded port than a blocked one before port noise will occur?

these are the values Win ISD calculates for the SP4. they are crazy far off from Fi's website. do the small parameters matter?

this is what i get when i use winisd. the graphs are always way off the scales and nothing like what i see others post on here. the specs of hte SP4 do not enter exactly but the tutorials say to just allow the program to fill in the blanks that it can and run with it so thats what i did. the spec that is the most off is BL: listed on Fi website as 13.7 and computed by winISD at 9.6.

ill give winISD another go. what is an example of slowed music? i was originally thinking of tuning to around the 35hz mark to try and get a bit more high end. tuning however is less of an issue than the port area as i intend to build the box with a series of ports to test it from 32-36 hz. a 6.5 cubic box i think is to small, not from a acoustic stand point but for the space in my truck. the box needs to be a minimum of dimensions for my plans back there. am i going to negatively impact my audio quality by building a larger box? if so is it because my amp is only a 2.5?

ok, ive had some suggestions on the 80-90 mark and you with 100 so it seems that the consensus is less than 150 for sure. id still like to have a more narrow window than 80-100. what happens if the port is to small?

from what ive read i want some where from 81 to 152 sq inches. the more port i have the slower the air but i dont really know how that effects the 'musical' side of things. do i want faster air for better notes or do i want it in the middle? im trying to understand the correlation to port air velocity and the frequency response/quality of the notes.