Harman Kardon AVR85

Agree with Scottht, that the rear level, is factory preset low and remembered by a battery-driven memory in the AVR85. Find the Rear Level option and increase the volume. The five amplifiers are an identical 85 watts, all channels can play at the same volume, with different surround information.

I had a same problem. My rear channel was never strong. After I changed the dealer, I learned that this particular rear amp is problematic. I still have the amp, but I no longer use it for surround sound, I bought another one and kept harman kardon in my bed room. Sorry.

You can adjust the level up or down. Have you tried that?

I have recently purchased an AVR55 and it has excellent rear channel output. Many sources do not have much rear channel information. Try playing a dolby-encoded music CD and see if the rear output improves. You may also want to borrow a pair of efficient rear-channel speakers made by a quality company. I also recommend inserting a regular CD player into the system to see if the problem can be isolated. If it isn't the source component or the rear speakers, the receiver may need to be checked over by a qualified technician.