▁to ▁produce ▁the ▁sound ▁of ▁a ▁full ▁concert ▁grand . ▁The ▁Stra ube ▁Ar tr on ome ▁player ▁piano ▁had ▁many ▁pat ented ▁innov ations , ▁including ▁one ▁that ▁improved ▁p ump ing ▁power ▁from ▁the ▁foot ▁ped als . ▁▁ ▁Roy ▁Hil mer ▁O ls en : ▁▁ ▁Pat ents ▁▁ 1 9 1 6 : ▁US ▁ 1 2 0 5 5 6 1 ▁A ▁– ▁" T one ▁Mod ulating ▁Device " ▁▁ ▁Ass ign ments ▁to ▁Stra ube ▁▁ 1 9 1 6 : ▁US ▁ 1 2 0 5 5 6 1 ▁A ▁– ▁assigned ▁to ▁Stra ube ▁P iano ▁Company ▁ ▁William ▁G . ▁Bet z ▁during ▁his ▁ten ure ▁with ▁Ste ger ▁& ▁S ons ▁P iano ▁Man ufact uring ▁Company : ▁▁ ▁Pat ents ▁▁ 1 9 0 7 : ▁US ▁ 8 6 7 0 0 2 ▁A ▁– ▁" P iano " ▁( str ength ening ▁how ▁an ▁ag ra ffe ▁is ▁mounted ) ▁▁ 1 9 1 1 : ▁US ▁ 1 0 2 4 1 7 4 ▁A ▁– ▁" Track ing ▁Device ▁for ▁P neum atic ▁Action " ▁▁ 1 9 1 1 : ▁US ▁ 1 0 3 7 5 8 4 ▁A ▁– ▁" H ammer - R ail ▁Const ruction ▁for ▁P neum atic ▁P ian os " ▁▁ 1 9 1 2 : ▁US ▁ 1 0 2 3 6 1 3 ▁A ▁– ▁" P neum atic ▁Action " ▁▁ 1 9 1 2 :