There is no balance pot in TU-8600
2CP601 is a volume pot.
http://www.tkd-corp.com/products/pot/pdf/cp600ps-e.pdf
2CP-601S (mechanical stepped version)
2CP601 is a volume pot.
http://www.tkd-corp.com/products/pot/pdf/cp600ps-e.pdf
2CP-601S (mechanical stepped version)