6x8 to 6.5in Speaker Adapters

I designed these to adapt my factory 6x8 speaker mounts to aftermarket 6.5" speakers. These were specifically designed for my 2013 Mazdaspeed3, though they will likely be a drop-in replacement for all Mazda3/Speed3 models for the 2010-2013 model years. 

These were designed to allow the Hertz Cento CK165 woofers to mount in the door without modifying any of the door structure. These speakers have a mounting depth of 131.5mm. According to after the install, this is likely the maximum depth of speaker you would want to mount in this particular arrangement. 

The models are marked ‘front’ and ‘rear’ based on which speaker location they were used in. The geometry is entirely symmetrical, so there is no mounting them upside down. 

I did use two speaker gaskets of 1mm foam sheet; between the door mount and the adapter, and then between the adapter and the speaker. This adds about 1mm overall of depth after the foam compresses. 

I printed the adapters in PETG for it's increased thermal resistance. Infill was set to 25%. They came out very rigid, and so far they sound great. They've been in use for about five months at the time of posting.