The  D10SUB  ceiling  mount  subwoofer  provides  powerful,  high-impact  bass response  intended  to  augment  any combination of Distributed Design Series full-range models.  By including a complement of D10SUBs into a distributed system, musical results that equal or exceed that of much larger and more costly surface-mount systems can readily be  achieved.    The  D10SUBs  clean,  clear  bass  response  provides  a  compelling  attraction  for  shoppers  in  a  retail environment, and a memorable experience for bar, pub and restaurant patrons.      Dependent on program content and the size of the full-range Distributed Design models, the ratio of D10SUBs to full-range models may vary from as few as 1:6 to as many as 1:1.  For example, one D10SUB will provide strong supporting  bass response for six D4s or D5s, while four D10 SUBs will better complement six of the more powerful D8s or D10s.      Like all Distributed Design models, the D10SUB installs quickly and easily.  Exclusive Drop-Stop and Twist-Assist Tabs allow single-handed placement to speed the installation process.  Drop-Stops spring-loaded legs support the back  can on the included tile rails and snap-on C-ring, so that the installer no longer needs to hold the can against the tile  while tightening the clamps.  Twist-Assist performs a similar function for the baffle assembly: when the loudspeaker back  cans are pre-installed into a conduit system for termination at a later date, a simple twist of the baffle into the back can brings the Twist-Assist clips together, supporting the baffle assembly while the installer fastens the screws.    The  front-face  wattage  selector  switch  enables  quick  adjustment  of  levels,  while  the  high-power  internal  autoformer permits full power output with 70V or 100V lines.   A variety  of installation accessories are available to accommodate different ceiling materials.  The D10SUB face-only assembly and D10 back can are also available for separate purchase.   All models in the Distributed Design series comply with ETL standards, including UL1480, UL2043 and CSA60065.