I'm not sure about newer Icepower but older modules, including one in my Rowland 102, have this problem. It is because of usage of single supply while reversing direction of the speaker using 4 Mosfet (switches) bridge. That way, half of supply voltage appears on both speaker wires. This supply voltage can be as high as 80V in some modules. There are types of class D modules, like Hypex, that use dual supply with one speaker wire fixed at GND. Channel Island used such modules. If you have any DC voltmeter measure voltage (without the music) from one of speaker wires to chassis or GND of input connector on your sub.
Recent sound deterioration shrillness, ringing
Because of recent speaker changes I've been flooding the forums trying to accommodate these changes and have run into a problem. First, for purposes of this discussion, the chain of components that I'm dealing with is this: Apple TV - Peachtree Audio preamp - RCA TO XLR CABLES - Behringer Ultracurve DEQ2496 EQ - XLR cables to Peachtree 220 power amp - speakers. Using other sources, the problem is the same.
With straightforward RCA connection from preamp to power amp everything sounds great and when I first hooked up everything as described above, it also sounded good. However, that's no longer the case; when hooked up through the EQ the sound turns somewhat shrill with what I would call a somewhat "ringing" effect to it even with the EQ power off which defaults to signal pass through. I've checked all connections for proper polarity and found them all to be properly connected.
Leaving the EQ out of the chain would be the first obvious choice for resolution but using it is the only way I have for connecting a subwoofer. One thing that crossed my mind is that, during setup I accidentally connected the preamp output to line out instead of pre out and thought my walls were going to cave in before I got it shut off.
I hope I've provided enough info for, at least some speculation and will appreciate any ideas that come to mind.
With straightforward RCA connection from preamp to power amp everything sounds great and when I first hooked up everything as described above, it also sounded good. However, that's no longer the case; when hooked up through the EQ the sound turns somewhat shrill with what I would call a somewhat "ringing" effect to it even with the EQ power off which defaults to signal pass through. I've checked all connections for proper polarity and found them all to be properly connected.
Leaving the EQ out of the chain would be the first obvious choice for resolution but using it is the only way I have for connecting a subwoofer. One thing that crossed my mind is that, during setup I accidentally connected the preamp output to line out instead of pre out and thought my walls were going to cave in before I got it shut off.
I hope I've provided enough info for, at least some speculation and will appreciate any ideas that come to mind.