Subwoofer Out to Mains?


Subwoofer has both low-pass in and high-pass out, balanced + RCA option on each.
Preamp has only one set of balanced outputs. Sending balanced out from pre to stereo amp running
the main speakers means either preamp unbalanced out to sub, or amp unbalanced loop out to sub.

But suppose one runs the balanced out from the pre straight to the balanced in of sub,
then runs balanced out from sub to stereo amp using high-pass. Just read a piece by REL which says bad idea,
even if you set it at 30Hz, since the rolloff  then begins at 60Hz, which is a sweet spot in the mains you don't want to lose. Well, this sub can't cross over below 35Hz, low pass or high pass, though it can roll off at -24dB/octave.

Q1. Does it actually matter whether the main amp is taking balanced input while the sub takes unbalanced?
Q.2: Who cares whether you are using the low pass or high pass crossover if both are limited to 35Hz?
Q.3: Anything inherently wrong with wiring sub amp ahead of main amp in the signal path?
Q.4: Any preference between pre out to sub vs. amp loop out to sub?

hickamore
Very bad idea. The sort of subtle degradation that happens with every connection and that is very easy to hear through the mains is all but impossible to hear through subs. Therefore, do everything you can to make the mains as direct and pure as possible, and give whatever is left to the subs, and don't waste a moment worrying about your subs.


+1 to Millercarbon.  Do the shortest and  best possible connection of primary signal to preamp, amp and speakers. Then worry about the subwoofer.