Explore FI Car Audio for high-performance subwoofers made in the USA, designed to deliver exceptional sound quality and durability. Discover our expertly handcrafted products, perfect for audiophiles and car enthusiasts alike. Upgrade your in …

The SP4 PLUS Series is the latest in the progression of Fi SP4 series of subwoofers geared towards thundering daily drivers. Adding a second 10″ high grade magnet provides the increased Gauss over the standard SP4 while 4 Fi designed 10″ heavy progressive spiders keep things under mechanical control.

The SP4 v2 Series is the latest in the progression of Fi subwoofers geared towards thundering daily drivers. Starting with a monster 4″ voicecoil for increase thermal capacity, we built the rest of the sub around that.

SP4 Subwoofer Neo4.7:The SP4 PLUS Series is the latest in the progression of Fi SP4 series of subwoofers geared towards thundering daily drivers. Adding a second 10″ high grade magnet provides the increased Gauss over the standard SP4 while 4 Fi designed 10″ heavy progressive spiders keep things under mechanical control.

The SP4 is listed as having an Xmax of 34mm and it does indeed have a ton of mechanical stroke with the maximum deep bass output being among the top handful of 18 inch drivers that have been tested.

Technical parameters and comparison of the Fi Car Audio SP418D1 18″ Subwoofer 2x1Ω · Resonance frequency 24Hz · Power handling 6000W · Sensitivity 88dB · Xmax 33mm

2016年3月4日 · I am curious to know why you are wanting to build a Ported Enclosure for the SP4 when you are more concerned with SQ? Plus you are placing it in a car that really doesn't allow for a lot trunk space and you want to cram a 3cube enclosure into it.

Technical parameters and comparison of the Fi Car Audio SP418v2+D2 18″ Subwoofer 2x2Ω · Resonance frequency 24Hz · Power handling 7000W · Sensitivity 89dB · Xmax 33mm

Subwoofer Fi Car Audio SP4 V2 18 D1. Diameter 18 inches, Power 3500 W. Thiele-Small parameters: frequency of self resonance Fs=24.7 Hz, equivalent compliance volume Vas=153.7 l...

2013年3月27日 · Looking to build a custom box for my fi sp4 18. Any suggestions for a good box or even specs for that matter? Ported, 4th order, 6th order, etc? What are your thoughts on tuning as well? Was thinking of 31 or 32ish hz.