Speaker hum


Would going from a 90db sensitivity to a 98db sensitivity speaker uncover a hum? I've been doing all the plug / unplug / cheater plug moves and haven't found it yet. It started when I swapped in new speakers and it's making me crazy. I have a 2-20 amp duplex receptacles fed directly from the breaker panel, same buss bar and grounds tied together in the 4 x 4 box at receptacles. I have an Odyssey Stratos Plus stereo amp and a NAD - C 658 BluOS Streaming DAC/Preamplifier.
Ag insider logo xs@2xmastercraft1990
With speakers that efficient and an amp with a ton of gain, you’re likely hear the slightest hint of residual noise, coming from anywhere in your system. Why did you mate speakers that sensitive, with an Odyssey Stratos amp?
I cleaned up everything behind my rack and made sure the power and source cables don't intersect at all.  Unplugged everything from the preamp and when I remove just one channel between the preamp and the amp it stops. It seem a little louder now and you can hear it at a 4 or 5 feet.

I have a cable hooked to the cable box to the AV receiver that connects to the preamp for using the mains for the front channels in a HT bypass in a 5.2.

The outlets feeding the system are straight from the breaker panel, nothing else on the circuit, but I have 3 different light switches with dimmers for LED lights in the room on their own circuit.

I didn't know that I was shooting myself in the foot by pairing HE speakers with the Odyssey amp.