BASSBOSS Questions

Hi, I'm looking into getting one of your DJ118 subs, but am wanting to understand how it would fit in to my stereo signal feed. Since I would only be using one subwoofer, I'm interested in knowing how I could feed both channels into the sub (like below) to be sure I'm not losing any information in the lower frequencies from both channels. Is this doable, and if so how would I go about


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David Lee

Great question, and one there tends to be some confusion about.

There is no appreciable benefit to hooking up two channels to the subwoofer rather than one. If the argument is that you need two channels for the signal level, that can be corrected with the gain

Hooked up as shown in orange in the diagram, you still get stereo tops. You still get the same level of low frequencies.

The benefit to NOT hooking up two channels into one subwoofer is that there is no phase shift between the inputs to reduce impact and detail and lose energy.  (And you save yourself the need
for one XLR cable)

If the low frequency information not in stereo, it makes no difference which channel is hooked into the subwoofer. (Most producers record the low frequency instruments and kick drums in mono. Most live performances are necessarily in mono.)

If the subwoofer (low frequency) information is in stereo you MUST have two subwoofers to take advantage of it. The stereo effect is dependent upon two separate acoustical sources.

If you hook up two different (aka stereo) signals and sum them, you lose energy and detail because the two signals are not identical. The two signals must be in phase for absolute summation. If there is a slight difference in phase (aka time) between the left and right signals, a loss of energy will result. The impact of a drum can be seriously compromised with only a slight offset of phase. There is phase offset in low-quality D-A converters, and there is phase offset in phonograph needle pickups so the problem doesn’t have to be in the recording, it can be in the equipment.

Try hooking up any subwoofer as in the attached diagram above. Adjust the gain to get the right level and listen to the detail. Then hook in the other channel and reduce the level to match the previous level. You either will or will not be able to tell the difference. If you can tell the difference, it will probably be that the single input sounds more detailed. If you can’t tell the difference, then having two inputs makes no difference.

[The following diagram is how we would recommend you hook up your sub. It isn't important which channel you use. That consideration would be more a practical one depending on what makes sense for easier cord placement.]


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