Subwoofer setup is really not a difficult task. You just need to see the big picture. This article will show you how.
So you’ve got a couple of rooms where you think you might want to “crank it up”. During the design phase of your whole house audio project, you might want to wire for a subwoofer setup in those rooms. It’s simple if you think about it now but if you put it off for later, it can be very cumbersome.
First, some background on the how. These days, most subwoofers (you still need to check for this feature) will have both low level (RCA style connectors) and high level (speaker wire) inputs. Most of the time we use a subwoofer setup in a “theater”. Most of our receivers that we use have a subwoofer “pre-out” that is an RCA style connector.
In our case with a remote room needing a subwoofer setup, it isn’t practical to wire an RCA line all the way. This gives you some bad side effects. First, low level signals are very prone to picking up the 60Hz sound from our high voltage electrical wires…so we get that hum at the subwoofer. Second, the volume of the subwoofer won’t go up and down with the volume control on the wall in that remote room, as it is getting its signal from the receiver’s sub out…the main volume knob on the receiver is what will make the sub’s level adjust with the overall output.
So we use the speaker level inputs instead. The subwoofers that have the speaker level inputs take the speaker wires from the receiver first, extract the low frequencies needed by the subwoofer, then pass the rest to the output side of the subwoofer that goes up to the inwall/ceiling speakers.
Here’s how we do it.
When you wire your typical system, you’ll take the speaker wires from your speaker selector first to your remote volume control location, then on up to the speakers in that room.
When you want a subwoofer setup in that room (or just wire in case you want a sub in that room), start at the speaker selector to the volume control in the remote room, THEN to a location at floor level, THEN on up to the speakers in that room.
You’ll wire into a single gang low voltage ring or J-box. If you’re sure you’ll be wiring the subwoofer for use in that room, you can cut the wires for hookup later with a speaker wall plate. If you’re not sure and are just wiring for the future, you can just leave the wire uncut and loop a little in there leaving the whole line intact and put a blank cover plate over the opening.