SA-SERIES V.3 8" 500W Subwoofer2 Ohm Dual Voice Coil The SA-8 v.3 represents the pinnacle of low distortion, ported box 8 inch subwoofer technology. We built on our experience with the SA-8 series dating back to the original model which launched in 2010 to create something completely unique to the market. Every piece of the SA-8 v.3 has been custom tooled with the utmost performance and lowest distortion in mind. We started with a proprietary FEA optimized motor design engineered just for the SA-8 v.3 which features a large aluminum faraday right for low magnetic and inductive distortion levels. This motor is mated to a custom tooled and patented (US Patent D691595) frame which allows for a larger spider and superior clearances to nearly any other 8" woofer on the market today. The spider itself was custom tooled to achieve a very even compliance curve over its entire range of stroke and also features large tied down “XL” tinsel leads to handle incredible amounts of power and abuse. The SA-8 v.3 features a full 16mm of Klippel verified one-way linear excursion and mechanical capacity in excess of double the linear limits (around 2.5” peak-to-peak) to ensure that mechanical failures are nearly impossible. We also tooled an all new surround for the v.3 update with the same incredibly linear geometry as the Mega-Roll v.2 surrounds found on our larger woofers (X v.2 series and larger). The SA-8 v.3 takes a departure from its larger cone diameter siblings in terms of the voice coil ventilation. Just like its predecessor, the SA-8 v.2, we employed a solid pole-piece to maximum magnetic flux in the motor – but in order to reduce mounting depth we did not use a vented frame spacer and, instead, drilled vent holes around the basket base. In order to exceed the thermal performance of the v.2 model we added sixteen chamfered gap vents to the back plate to keep the high-velocity air flowing over the voice coil. In other words – the SA-8 v.3 will give you everything that you loved about the v.2 but with even more durability & even lower distortion.The standard SA-8 v.3 features a 4-layer copper voice coil wound on a black anodized aluminum former for the most possible low-end extension. We do offer SPL models with lighter coils and even "extreme SPL" models with harder spider packs and other impedance configurations (these must be custom built). We can use anywhere from 2 to 6 spider layers on SPL versions to tailor the FS where it needs to be for a given SPL application.Xmax = 16mm one-way by 70% BLRMS Power = 500-wattsVented magnetic gap featuring sixteen chamfered gap ventsSolid Pole piece with chamfered edges for increased air powered voice coil coolingHigh velocity under-spider frame ventsBlack Aluminum 2” voice coil former for superior heat dissipationHigh Temperature copper voice coil wireLarge Magnet ID aluminum faraday ringSpring Loaded TerminalsStitched-On “XL” Tinsel Leads to prevent fatigue and failureHigh strength & patented cast aluminum frameOptimized for small, ported enclosuresSA V.3 8"T/S SPECSSAV3 8″ D2SAV3 8″ D4RE (Ohms)3.366.0FS (Hz)38.2940.0VAS (L)6.887.17Qes0.3240.392Qms6.314.31Qts0.3090.36Le (mH)2.083.32BL (NA)18.9422.06Mms (Grams)144126.6Cms (uM/N)120125Sens (dB @ 1w/1m)82.7982.71 SA V.3 8"Sealed Enclosure0.3 cu ftPorted Enclosure0.65 cu ftRecommended Tuning35HzRecommended Port Area9 sq inDisplacement0.08 cu ftDepth6.625″Outside Diameter8.375″Cut-Out7.375″