http://www.tamadrum.co.jp/anniversary/expansion.php?cat_id=8&now=3
All this time we have been mis-identifying certain Star shells as "3ply". At the bottom right of this page in the Star catalog from 1972 the shell construction of this era of shells is identified as "9 ply compressed with hardwood rings". This is not to be confused with the earlier shells that are clearly thinner. These 9 ply shells are, from the best I can tell, ONLY the Star drums, not any of the stencils. If you have one of these kits, not the earlier kits, please take a moment to look closely at your bass and confirm this.