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Message: <blockquote data-quote="sundownz" data-source="post: 8324708" data-attributes="member: 549523">Got my first prototypes in for the v.3 revision of the SA-8 -- it took quite a bit of consideration to figure out how to make some improvements to the design but I think we are on the right track :<img src="http://www.sundownaudio.com/misc/protos/SA-8/v3_Version/1st_Protos/IMAG1176.jpg" alt="" class="fr-fic fr-dii fr-draggable " style="" />* Newly tooled surround with an improved shape / slightly bigger overall size... this is a new shape I have been testing with for a while that is a bit more linear than the old shape. It allows a small but noticeable amount of extra throw.<img src="http://www.sundownaudio.com/misc/protos/SA-8/v3_Version/1st_Protos/IMAG1177.jpg" alt="" class="fr-fic fr-dii fr-draggable " style="" />* We removed the vent ring to reduce the total depth by 10mm -- since this reduces the cooling capability a bit we added gap vents (next photo). I did use appropriately sized drilled vent holes to maintain a degree of pressure in the under-spider cavity to help push air to the gap vents and keep velocity high. I tweaked and tuned the vent hole size on the SD-2 8" model already.* A second but major benefit is this will help improve QC pass rates by reduced spider to top plate distance; thus reducing the chance for coil tick (fewer yard sale units thus steadier inventory).* The magnet stack increased to 50mm from 40mm -- and we reduced the back plate from 25mm to 15mm (removed the 10mm bump) to keep overall motor depth the same. A marginal increase in BL will be seen.* New magnet boot isn't tooled yet but will be for production.<img src="http://www.sundownaudio.com/misc/protos/SA-8/v3_Version/1st_Protos/IMAG1178.jpg" alt="" class="fr-fic fr-dii fr-draggable " style="" />* It's a tight fit in this motor due to the thick shorting ring... to get the surface area I wanted I used 16 gap vents @ 2.5mm each as wider vents wouldn't fit between the pole and shorting ring. Also each vent is flared to keep the flow quieter.----------There are a few other tweaks to the way the suspension goes together, standard XL leads, and a few other little tricks in the motor that you cannot see -- all in all should be a nice little upgrade to the SA-8 driver.I still need to tweak the stiffness a bit as it ended up a bit too stiff on the first two prototypes... so that is still under-way. I expect them to come out some time around the end of the 1st quarter next year (so end of March or so). Until then the v.2 will be in full stock and shipping as normal.</blockquote>

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