balanced vs. unbalanced sound quality

I know this is an old thread but it seems like it was made for my questions. I use a Rotel rb991 and an older pioneer elite vsx45tx as my pre on a two channel setup.

When I use rca connections I get substantial hum, my avr does not have balanced outs so to get rid of all the noise from the RCA’s I purchased an rca to xlr adapters and that took care of the hum but my volume decreased by half.

I do however have a stronger and tighter bass, actually the whole sound is now very uncolored, I have been told if I go to a pre that has balanced out to the amps balanced I will get some of my volume back because the adapters mute the signal in some way? Where I was listening at a pretty loud -30db is now at reference to come close to the old unbalanced connection.

Im a musician and I compare the difference in sound from unbalanced to balanced like playing my guitar through a high gain amp head without any processor, it’s dry and precise, the unbalanced sounds louder but like I added some delay and reverb, a very manufactured sound.

You guys seem very educated in all this and I’ve enjoyed reading what has been discussed so far,just trying to further my understanding by picking your brains.

I do however have a stronger and tighter bass, actually the whole sound is now very uncolored, I have been told if I go to a pre that has balanced out to the amps balanced I will get some of my volume back because the adapters mute the signal in some way?

The reason this is happening is because the Rotel employs two sets of inputs that are independent of each other. The balanced input converts its output to single-ended; that signal is then applied to the single-ended input.
The balanced input needs two inputs- non-inverted and inverted; if it only gets one (which is what happens when you use an adapter) then the gain is reduced by 6db which is pretty audible.

A balanced preamp would solve this.

Thank you atmashpere!