Guess: Shenzhen Concert Hall is state-owned, and now it is contracted to a private company and operated by the company. You can probably guess a thing or two by looking at their website.
As for the "Philharmonic Club" you mentioned, it is a club of Huading Culture Development Co., Ltd., which specializes in booking activities and renting venues. They charge drinks service fees and venue fees, and sometimes they often don't pay the final fee.
Philharmonic Club is located on the first floor of Shenzhen Concert Hall. Go straight for 20 meters on the right side of the door, and you will reach the door.
Bottom line: The public property of the concert hall is privately operated. The Philharmonic Club is a Philharmonic Club and the Concert Hall is a Concert Hall. Just the same house.
Disclaimer: Don't blame me for the above questions about whether the concert hall is private or not.