rca and xlr inputs connected simultaneously?


I have a Krell KSA 200S amp with both balanced and single-ended inputs. Due to long runs, I use balanced interconnects from my Krell HTS2 home theater processor's front channel outputs to the Krell amp.

I also have a Supratek phono preamp for listening to analog on 2 channels. I have single-ended interconnects between it and the Krell amp.

I have never connected both at the same time. If I'm watching a movie, I disconnect the RCA's and plug in the XLR's; if I'm listening to vinyl, I do the opposite.

I have no idea what would happen if I connected both at the same time. I can't imagine that it would damage the amp but since I don't know, I haven't tried it.

I know there are shorting pins that came with the amp which I insert into the XLR inputs when the RCA inputs are being used, but there are no RCA "shorting pins". Does that mean that if both inputs are connected, the XLR's take priority and the single-ended signal is ignored?

Any help would be greatly appreciated.

-Kyle
west99

Showing 2 responses by kr4

No. The shorting pin shunts one side of the balanced input, converting (crudely) the input stage to single-ended. Consequently, I doubt (without actual experience) that you can connect both at the same time.

But I would consult Krell.

Kal
"I don't understand Kal's description of this setup as "crude". It's just not balanced."

Agreed. The described method simply does not make use of the other side of the balanced input and, as you know, is pretty standard. This reduces the input gain but keeps the higher input noise of the balanced input. A switch to disconnect the other side of the input stage would be more elegant although more expensive. In practice, probably little or no subjective difference.

Kal