New project to keep me busy!!!

[bigred78797 10+ year member]

Well ive been bored lately and decided that i needed something to do.

On my first boredom trip i installed the car amp, battery and, charging system in my house.

Now that that's over with and ive gotten an unwanted break from my box designs i decied to do something fun.

I decided to give making my own sub a shot //content.invisioncic.com/y282845/emoticons/uhoh.gif.c07307dd22ee7e63e22fc8e9c614d1fd.gif

I will put up pics of my progress as it goes on but if you guys have any suggestions on any functions or additions let me know.

Here are some of the things that im looking to do with the sub.

two or four voice coils

adjustable spider compliance

Cone has been made out of fiberglass ( 11.5" of cone diameter 103.817 in squared of cone area )

2 inch to 2.5 inch surround still deciding on fabricating materials ( suggestions needed)

double stacked magnets Will weigh later

Any other suggestions just post here... any real suggestions.

Click to read more...

 

[Bavarian3 10+ year member]

wow that sounds pretty sik, be sure to post pix of ur progress

 

[marleyskater420 5,000+ posts]

I wanted to build my own sub,I still do.But I was going to buy the un assembled pieces from RE but it costs more to make one than to buy one.The glue and coil winding is expensive.

Are you going to make it purely out of things around you?

 

[bigred78797 10+ year member]

Yeah im gonna be making most of it out if 3-4 layers of fiberglass cloth. Ive gotten pretty good at fabricating parts out of this stuff. The cone is made out of 3 layers of fiberglass cloth. I think i made it too heavy i mean i can stand on the cone without it even budging. For most of the glue im gonna be using fiberglass resin ( just because that's all i have other than elmers glue ). Because the cone is soo heavy i might have to increase the voice coils to 4 to 8 to get a Crap load of BL. For the spider suspension i was planning on using some kind of air suspension.

Like a plate between two air bags that are adjustable in air pressure. Im not sure if it would work but that's why im making this so ill know what works and why it wont.

Im not making this sub to be competitive to good subs by any mean, i actually have really really low expectations for it. I mean it's gonna look really nast actually //content.invisioncic.com/y282845/emoticons/sick.gif.b1847c8dabbfeeddbcf1a78052249e10.gif and probably sound that way too.

Just one question it's been a while since ive actually seen a voice coil and i couldn't remember whether or not each turn was touching the previous turn or if there was some kind of film around to keep it from touching each other. Are voice coils made of shorted turns?

 

[bigred78797 10+ year member]

Here are the pics of the basic cone. I just have to add an edge to it so that the surround will be attached easier.

 

[n0ftInc 10+ year member]

Nyce work.. Looks like two old ******* to me.. :hilarious

 

[bigred78797 10+ year member]

Well i got almost halfway into the building process and figured out i needed to do alittle more planning rather than just going out and making parts that don't fit. So i scrapped the old speaker and started over. Everything is the same except for the size, instead of a 12" circular cone, i decided to go with square cone, makes it easier to find a suitible surround. I know the corners will be weak but i don't expect it to last that long, especially after i plug it into the wall. I remade the cone, using only 1 layer of fiberglass matting between 2 layers of fiberglass cloth. needless to say it's much stronger than my last cone. I designed the entire sub using a CAD program and have all the parts desighned except for the magnet structure ( still waiting on that from my cousins blown speakers. They are three 80 oz magnets... im triple stacking them :thumbsup . Oh well any way here are a few pics of the design don't have my cousins camera with me so i can't take the pictures of the sub cone and suspension.

For the suspension i used bike innertubes that are pulled really tight and can be filled with air or air can be released to decrease or increase the tightness of the compliance. For the surround i used some type of water pipe insulator, it's 2.25 inches outer and about 2 inches inner diameter. For the corners i used this really strong sealant that the guys at home depot suggested don't remember the name but after i glued the test surround togeter i couldn't seperate the two pieces by yanking it as hard as i could and it still remained flexible at the glue point.

For the voice coil i used copper wire creating 4 voice coils that are 90mm from top to bottom... alot of wire. The voicecoils are wrapped around a copper former to help get rid of the heat, it also lowers my qms greatly hopefully below 4, which is better for ported enclosures. But i did alot of things to the voice coil former that i really hope will get rid of the heat. I don't remeber the AWG of the copper wire i used but its about 1mm to 1.5 mm thick so im expecting a somewhat low resistance for the Voicecoils. But anywhoo here are the pics of the design. What i made even suprised me on how strong and how well made and how closely they resemble what i designed.

 

[ice00 10+ year member]

how hard is it to make ur own subs???....and steve(n0ftinc) is right...they do look like two old *******

 

[bigred78797 10+ year member]

To me the hardest part is fabricating the parts. Once you get your technique down and become consitent on making the parts it's pretty easy. My sub is basically a trail and error sub while other subs are made using programs like SpeaD and reverse SpeaD. What that means is i have know idea what the Qes, FS, Qms, Vas, etc is gonna be until after i make it.. and i still probably wont know. I can only do things that i know lower or raise those parameters to try and get within a targeted range. To me the designing is pretty easy because ive been enginerring and creating stuff all my life with computers and i do a good job of visualizing what it should look like in my mind. Oh and the two ******* were scrapped. I now have a 18.25" square cone. 18.25" side to side not corner to corner so it's a TRUE 18" subwoofer.