Need Combo line/speaker level switch for sub

[mgkman]

Just bought a new Subwoofer. I want to use it’s speaker level inputs for 2 channel and line level inputs for HT. The sub manufacturer des not recommend feeding both inputs simultaneously. I need a simple switch that can cut speaker level when line is used and vice versa.

Niles SAS-1 does this automatically but I want a low cost solution with one manual button/switch to change sub inputs. Should be fool proof so I can’t accidentally feed line and speaker level to sub simultaneously.

My electrical wiring knowledge is limited so I need something simple. Any ideas?

FYI sub amp is KG-5230.

[richie00boy]

Are you using two different systems with the sub then? Otherwise I can't see why you would want to do it.

[mgkman]

Yes I have a 2 channel stereo system for CDs and HT receiver for DVD movies and TV.

2channel stereo=Arcam CD, Levingson Pre, Classe Amp, Hales spkrs, custom built sub.
In stereo mode I feed the sub with an extra set of wires coming off the Classe amp speaker connection.

In HT mode the Harmon Kardon AVR500 receiver and stereo system work together. I feed receiver front rh and lh pre-outs to the two channel system in pass thru mode (receiver controls the volume). So the HT receiver amp powers only the rear and center channels. The subwoofer gets its signal from the HT receiver sub out line level.

But with both systems on the sub gets two signals. I want to send it only speaker level signal when using the stereo system and line level signal from HT receiver Sub output for HT.

[richie00boy]

Just use the 2-channel speaker level connections and tell your cinema amp to send the LFE to the front left and right channels. Leave the sub crossover set as you have it for music.

This is what I do and is actually the best way if you have anything better than average front speakers.

[mgkman]

Good idea to run LFE to the mains right left with the Harmon Kardon processor. I have a couple other options of making my own black box with a 4 pole double throw switch, or abandoning speaker level and trying an A/B switch on line level.

I looked at the owner’s manual for my HK receiver and I think your suggestion will work. It’s certainly the easiest and least expensive route and I won't need to defeat the subs cross over every time I want to switch between movies and two channel listening. I'll let you know if I like the way it sounds.