I also have the JBL 530 speakers in my current setup. While I don't have a Denon AVR, I do have the Pioneer SC.81. I've used a separate power amp to drive the 530s for the past month since I received them. One night with a few hours to spare, I re-worked my setup thinking that I could possibly remove the power amp from my equation since I live in a condominium. On my Pioneer, I set up the 2 SB channels for bi-amp mode. Ran appropriate cables to the 530s. Thinking that something would be gained in applying a 105 watts or so to each of the binding terminals. The result? For me, using the amps in the Pioneer left the JBLs sounding a bit anemic. I then stayed up a bit later to reverse this change and put the amplifier back into the picture. At this time, I'm just using the Pioneer as my pre-amp and for the ESS Sabre32 DAC that it has. Otherwise, the rest of the chain is a MiniDSP that splits off into 4 outputs. 2 going to my amplifier inputs, and 2 going to my 2 10" Monolith subwoofers. With this configuration, I can keep the Pioneer in Pure Direct mode and still have the subwoofers utilized.
Over the past few months, I've been playing around with several amps. The Crown XLS 1502 came to mind, but then I was reading up on the Behringer A800. I ended up getting the previous model, the A500, locally and tried that for a week before opting for the A800. There was a negligible change in the sound, if any between the two amplifiers. Then, a Behringer NX6000D popped up locally that was available, so I sprung for it. Granted, it has fans, but the A500 and A800 didn't. So, I purchased 2 80mm 22dB 5V computer fans and was able to eliminate 98% of the fan noise. I'm quite content keeping a separate power amp to drive my JBL 530s as the Pioneer provided amplification just didn't cut it for me.
