Using Bose L1 Compact with HD500

[stevecu]

I just picked up a Bose L1 Compact PA to use with my HD500. 

 

I initially ran a TRS cable from one of the 1/4" out jacks to Channel 2 on the L1 (with the switch set to Line Level). It worked okay, but I got a lot of noise at modest volume settings (approaching 12 o'clock) on the L1. I've tried a couple of cables and the noise persists. I've seen posts indicating others have had similar experience, and resolved it by using a TRS to RCA Y cable. I've cobbled together such a cable using a TRS extension, a 1/4" to 1/8" converter and 1/8" to RCA Y cable and it works great. 

 

I want to replace this cobbled together mess with a proper cable, but I wonder if I'd be better off a dual TS to dual RCA cable. The PA is mono, but it seems like grabbing both left and right would avoid issues having to adjust the pan settings on the mixer. The TRS to RCA setup works great using the headphone jack also, but I'd kind of like to keep that open for ... headphones. 

 

Any advice appreciated.