Subwoofer Building basics - Setting Voice coil Height 

You are very welcome!! I’m always glad to help if I can!!

I've got one of those I think they are the perfect size being in between an 18 and a 15 and I love the bolt together way they do things it makes life so much more faster the only problem is their motors are the weak point the glue is crap so they shift easy but this is an easy fix just swapping the motor with a better 4" coil motor like one I did a while back was a 15" hcca with a American bass xmaxxx monster 15 motor so it had 150oz more size and almost 1" inch deeper for more xmech and rated for 1500w rms more and let's just say that thing put the cool kids in the back of the buss lol

Had a hcca 12 from 1999 and had it on 1ohm, 3.5" ported mdf without sub weight was 90lbs. Had it at a 2.75 excursion and put bout 2500watts with a 2100hcca on 1 Guage wire.

Hi Jim, Thanks for checking out Mr M. Dual voice coils can be manufactured in several ways. Typically they are superimposed such that the first set of windings is adhered directly to the voice coil former (Usually aluminum) and the second is wrapped around the outside of the first windings. Depending on the specific coil they can be 4 or 8 layers. In a 4 layer(layers of wire), layers 1 and 2 are one coil and layer 3 and 4 are the second coil. It is also possible to make a bifilar voice coil in which both coils have their windings in every layer... They are not very common and I do not think I have actually ever seen one... I will spare you the explanation on this one because it hurts my brain to think about... Dual voice coils provide more wiring options for different amps, speaker combinations etc... no, they are not really necessary. As for silver... I have contemplated this many times.. But.. I have never tried it and I imagine the cost implications would outweigh the functional benefits.. Cheers, and thanks for you questions!!

You are very welcome! Not sure where you got your replacement parts but I normally order from Lord of bass, if they don’t have what I need PSI (fixmyspeaker) or Springfield speaker repair are other options and if cost isn’t a concern gs audio Italy makes really high quality coils but they are pricey.

@@MrM_Full-Send went through LOB and sadly psi doesn’t have the same coil 😞 so I’m kinda just stuck waiting it seems

@@jeffschultz1190 😒. I just tried to order 4 12” frame gaskets but LOB would only let me order 1 …. So it seems I’m in the same situation 😅🤷‍♂️.

@@MrM_Full-Send ya it sucks, I’m waiting on one D1 8layer 3” fw aluminum coil lol

like for pairing subs or wiring configurations for individual subs?

i love the hose clap!! use couplers they come with rubber 2.5, 3, 4 inch and the claps then just cut a section out to get the correct circumference and adjustability. and always remove before you glue the cone assembly in. Certain baskets would make it hard to get off after

@@MrM_Full-Send most definitely using it for my current build. I’m glad I ran into your channel.

yes this is the 165oz 2” vc motor from lord of bass. you are very welcome!!

I only do car speakers 🤣. yes it is the same method for all speakers however there are some variations for different motor styles. overhung and neodymium are a bit different. same principle but additional items to consider

@@MrM_Full-Send What solution would you suggest to increase the bass of the speaker

@@Saeidcaraudio the enclosure is critical. if not ideal start there. typically Subs are designed to optimize performance within the ability of the parts being used. this means there are limited opportunities to increase their performance. Not always the case but more often than not.

I build lots of custom subs😊

@@MrM_Full-Send how do I get in contact with you? For a quote

i would say the new voice coil is almost definitely aluminum. as far as height of VC goes, there could be two issues. 1 the height was not set correctly and so the Windings are not properly centred on the motor top-plate (this will be unlikely to correct over time) or 2 the wrong voice coil was used and does not have the correct winding height but is centred properly. either way the person who repaired it did it incorrectly🤷‍♂️. it should be built to match original as close as possible IMO

@@MrM_Full-Send thanks for clarifying! Man that sucks.. I've been looking to get these subs for a very long time.. I would love to get these repaired but it's a question of finding the right person to get the job done correctly 😞

yes. the hose clamp would cause serious functional issues if it was left on when you glue the cone assembly into the basket 😳

@@MrM_Full-Send Yeah but you leave the clamp on there until you’ve finished glueing the cone on then pull it off and shim and glue the spider though.

@@edwardmatthews5899 i leave the clamp on for the entire cone assembly process. then pull it off right before i glue it in to the basket

I am in canada so shipping might be prohibitive

this approach works for most motor set ups. it’s a bit more complicated for neo motors because they have a “fake” top plate and overhung motors but generally speaking this is correct

you need to know what basket and cone you are using. and motor to figure out where the coil will be positioned and where the bottom of the cone is. then you can determine how long the former needs to be… basket has two critical heights. surround seat to spider seat and spider seat to mounting flange. add the two basket heights. then subtract cone height. this gives you the distance from the motor top plate to the underside of the cone (provided you are not using spacers). take that number and add x-max and motor top plate thickness. now you have the distance from the bottom of the voice coil to the bottom of the cone. add 3/4” to 1” so your former is long enough to pass through the cone and have enough length to glue the cone to. contact me on FB or Instagram or email and i can send a picture to clarify this explanation

​@MrM_Full-Send Thanks! This helps clarify things a lot for me. If I have any more troubles I will contact you. Again thank you very much!

😊

measure the wires on the voice coil. i normally use digital callipers but you could do it fairly easily with a tape measure.

The question I have is how do you determine which coil (former) to buy because they have different winding height formers

​@@Ljtaz1122measure your motor depth and top plate thickness to determine winding width or height. Also measure your top plate thickness, and from your top plate to spider landing, plus any spacers you will use if you use one. That helps determine overall former height. Make sure to purchase a cone with the proper depth so that the former reaches the cone neck, and will still give you a little former exposed up top as a glue joint. You can buy a coil with too much former length and cut it down. 👍

I wanted to buy two for a pair of subs I’m building but that project is back burner right now 🤣. Last time I looked they were out of stock

coil was originally bought for a custom sub built on an RE destroyer motor but the motor has a tight vc gap so 8layer wouldn’t fit. Orion HCCA uses a similar VC. the Audiobahn AWT15X i built had a 4” VC as-well. i will be putting that particular Coil into one of the GSA Industries 12” Assassin Prototypes