My experience in connecting a Pass preamp to a Pass amp is that balanced is notably superior. Every setup though is unique and my experience is what works for me.
Single Ended or Balanced -- a Difficult Choice
Circumstances recently gave me a chance to really compare the sound of single ended vs balanced connections in my system and the results somewhat surprised me. I've always believed balanced (implemented correctly) to be superior and had been running all balanced cables throughout my system. However with a pending switch to a new phono stage which is single ended only I have been having AudioQuest re-terminate my various WEL Signature/Horizon cables as single ended.
Where I got surprised was between my DCS Vivaldi DAC and my pre-amp (ARC Ref40). Much to my amazement the single ended connection sounds markedly better than the balanced. With the latter there is a definite edge and lack of continuity to the sound. Vocals and leading edges seem forced and you miss a sense of wholeness and seamlessness to the sound -- especially apparent on vocal. It's a difference that you only notice after you hear it, but once you've heard it it's very noticeable. Obviously this is all after adjusting for the different output level between these two connections.
Overall the lesson learned is to take the time to compare the two if you have a choice -- and if you have identical pairs of cables available with each termination. My rule of thumb going forward will be to stick with single ended for single ended circuits, as going balanced is just introducing another active stage with the negative consequences as above (of course I'm assuming the Vivaldi DAC is not a balanced circuit at the output but who knows)
For my big run pre-amp to VTL MB-450III I stick to balanced as for a 10M run single ended is not an option, besides which both of these are balanced circuits as well
Anyway a helpful and surprising lesson and I'm sending my last balanced shorter interconnect back to get it changed!
Where I got surprised was between my DCS Vivaldi DAC and my pre-amp (ARC Ref40). Much to my amazement the single ended connection sounds markedly better than the balanced. With the latter there is a definite edge and lack of continuity to the sound. Vocals and leading edges seem forced and you miss a sense of wholeness and seamlessness to the sound -- especially apparent on vocal. It's a difference that you only notice after you hear it, but once you've heard it it's very noticeable. Obviously this is all after adjusting for the different output level between these two connections.
Overall the lesson learned is to take the time to compare the two if you have a choice -- and if you have identical pairs of cables available with each termination. My rule of thumb going forward will be to stick with single ended for single ended circuits, as going balanced is just introducing another active stage with the negative consequences as above (of course I'm assuming the Vivaldi DAC is not a balanced circuit at the output but who knows)
For my big run pre-amp to VTL MB-450III I stick to balanced as for a 10M run single ended is not an option, besides which both of these are balanced circuits as well
Anyway a helpful and surprising lesson and I'm sending my last balanced shorter interconnect back to get it changed!