Using both balanced and single ended outputs at the same time?

I have a BHK pre with both balanced & RCA out. The BHK instructions state one of the uses for the RCA’s out we’re Subs. The only issue is the balanced out was +6db, as @cleeds said over the RCA out so had to adjust the sub volume up to compensate. 

Well you always have to adjust the sub (s) volume.  This is not a negative nor an issue.

On my Krell Illusion and Krell 300xd they both have Balanced outputs and Rca outputs along with inputs So I use high quality locking xlr connection between units.

@cleeds the noise in the listening room with swamp that difference.

Some visitors to this thread might not understand that there are two types of circuits in stereo audio components: ’single-ended’ and ’balanced’. Single-ended is also known as as SE.

An RCA connector is used on a ’single-ended’ circuit. An RCA connector cannot be used on a ’balanced’ circuit. An XLR connector is only used on a ’balanced’ circuit. BUT, an XLR connector can be used on a ’single-ended’ circuit. It is simply piggy-backed on to the RCA wiring. Several manufacturers provide both RCA & XLR connectors on a ’single-ended’ circuit simply for convenience. (No need to buy new cables.)

A truly-balanced differential circuit is considerably more expensive to implement. A manufacturer will feature this design in their marketing. The benefit of balanced is best realized if all the components in a chain are also balanced. As with everything else in audio, ’single-ended’ vs ’balanced’ is subjective. They each of their advantages & disadvantages.

Having XLR connectors on a component, does not automatically mean that the circuit is balanced. And there’s the option of converting a single-ended circuit to balanced by installing a transformer. This would be for a different discussion.