subwoofer connection quandry

Thanks, Loomis & TLS. There's no technical issue connecting just one output channel, but obviously it won't be sonically optimal with recordings having deep bass content that is not centered (i.e., that is not recorded equally in the two channels, to a close approximation). As Elizabeth indicated in the other thread that probably won't be an issue with many or most recordings, but IME it would definitely be an issue with some.

The resistor-based approach TLS describes amounts to implementing a passive mixer, and can work well. In fact in the other thread I linked to there is a link describing exactly that, although with resistors in the 5K to 10K range. What value is optimal depends on the impedances and other characteristics of the particular components, and also perhaps on the length and characteristics of the cable (although that probably doesn't matter much if at all in an application such as this where effects on high frequencies aren't a concern).

In this case the output impedance of the NAD's sub output and the Hsu's line-level input impedance do not appear to be specified. But my suspicion is that the resistor value that is chosen is probably not very critical. If I were to hazard a guess I would say go with something in the area of 1K to 3K for these particular components, if that approach is pursued.

Best regards,
-- Al

al et. al.: thanks for the input. i should have found the earlier thread, which was expressly in point, but i drank too much cough syrup last night, which is interacting very badly with my pysch meds.

Thanks Al, I just looked at the link in the other post, and that is definitely the adapter I made. I found that using a larger RCA connector like this one, it was fairly easy to secure and conceal the resistors inside the connector, making the adapter cable sturdy and having a very clean appearance.

Al and others ... the OP's Q reminds me of what I had to do to solve my sub-woofer issues. Rather than repeat everything I said before, I'll just put out there that the solution to my sub-woofer problem was picking up a custom made impedance buffer that summed the L/R channels without shorting the linestage's main outputs. In addition, I needed to raise the impedance presented to my linestage. The custom buffer handled all of these issues and one or two other issues as well. Read the link Al provided for more information if interested.