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Custom Build 21" subs

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Have any of you made your own subs before? I was looking at prices of individual parts and I'm thinking I could make some sick 21" subs for about $500 each. I was wanting to upgrade to FU2000 SPL 18s but after taking the FU750s apart I realized how cheaply made they are. I can get a Quad stack 4" motor for like $250, the TI style 21" baskets with a custom welded 12" spider landing with triple medium linear spiders with dual sowen leads on a 4" 8layer team coil with tall roll surround. I am sure I could put then together if not the guy I met who reconed my subs said he would help me. He is who told me about making custom subs and that it's so much cheaper to make ur own. He said they will be like 2500 to 3000 RMS easy and that they will get super loud and low. Just curious if this is something most of y'all do or is this kinda of like an odd thing to do?


He said if I make these 21"s and do a huge 4th that I could get to 160dB probably with a good enough amp. His single 18" that he made with a 100lbs quad stack motor takes 3000w at .5 ohm full tilt all day. He gave me a lil demo and it was definitely alot louder than my 2 18s. But his was in a 4th

93 Dodge Caravan

Excessive Amperage 300amp Hairpin Alt

JVC KD-X340BTS, 2x FU750v2.0 - 18"

12CFT Net Vol. Ported Box Tuned @ 32hrz

Aphard Sound Machete M2000D

3x 100aH Power Sonic Batteries

Sony 5.25 4ways(Dash)

Kicker 6X9 3ways(Rear Hatch)

2/0g AWG OFC Welding Cable

8G AWG OFC Speaker Wire

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2016 Focus ST3 - Rockford DSR1 / PPI 900.4 / Silverflute 6.5" mids / Massive CT2 tweeters /Sundown Xv2 15"/ Taramps DSP3k / Stinger Roadkill / KNU wiring / Northstar SMSAGM80 /

2010 Focus coupe 157@46hz

Pioneer 80prs /(8) FU Audio 750 12"s / (4) FSD 2600s / (1) FSD 125.4 / (1) FSD 85.4 / (4) Crescendo UN-10" mids / (4) Crescendo FT1 tweeters / Stinger Roadkill / 2/0 EB flex wire / (5) Powerware 90AH batteries / DC 270XP Alt /


too many freq at once, burn the coil, we all know, over 40-50hz, its all coilburning material.

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A motor and coil stronger enough is gonna cost 350+ per motor. You don't need much throw. 15mm overhang is plenty.

Good luck on finding a cone worth using that isn't so heavy you need 5kw.

i told wife guy on here pm'ed me wanting to buy my amp she said tell him it not fs (cause she knows i'll spend more $ on new one) and told her i wanted d2 sub for bday next week she said tell ya'll i'm to old to go down to 1ohm lol..

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