Yeah I agree about tweaking. I modified my 500i amps by changing the speaker binding posts to proper larger gold-plated ones, and in so doing, removed the Zobel-network-like circuits that were on the tiny micro-PCBs that the original binding posts were connected to. Mechanically an unusual arrangement. So now, that intervening circuitry is no longer in the signal path.
There was a risk that by removing them, I'd allow the amps to become high-frequency, high-power oscillators and destroy my tweeters, but the gamble paid off, and everything *is* stable.
I also modified my Dynaudio Audience 52SE speakers; they were supplied NOT bi-wirable. I'm into early middle-age now, and I spent 16 years nightclubbing an *average* of about twice per week. So age and noise exposure have taken a bit of a toll on my treble hearing (not dreadful, but it's there). So I had to take the speakers apart (my expensive babies!) and open up the crossover PCB by cutting 2 tracks on each, and lead out to a new pair of binding posts on the back of each speaker, so that the woofer circuit could be driven separately from the tweeter network.
Then I could use one of the 500i amps to drive the L & R woofers, and the other to drive the tweeters. Then I could set them at different volumes, without having to add any nasty tone controls to the system. I use the amps with the "CD Direct" enabled, to defeat the amps' built-in tone controls.
Finally, after a lot of work, it all worked, and it sounded very nice indeed!
The photo is a bit grainy, because it was a 30-second exposure at very high ISO, in a room that was in fact pitch black apart from the things that were glowing. I couldn't see the camera on its tripod!