The best way to connect a sub

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We touched briefly on subwoofers and speaker setup in yesterday’s post. What I didn’t cover is how best to connect a subwoofer if you choose to go the extra mile and complete your system.

Years ago, there were mostly passive subs, but over time this changed. Modern subwoofers are internally amplified. So it might seem intuitive to connect them as you would any power amplifier, with an interconnect to the preamp or DAC. This works, but would not be my first choice.

The problem with cables and subwoofers is two-fold: double-long interconnects and a missed opportunity and synergy.

Preamplifiers aren’t especially appreciative of the cables that connect them to amplifiers. Shorter is better if you can manage. Worse is when you double up the cables: one to the loudspeaker amplifier, the other to the subwoofer amp. A much cleaner, better sounding way of doing this is with the use of a Y connector at the amp. In this scenario, you have one cable between the preamp and amplifier (with a Y connector at the amp’s input). A short interconnect from the Y connector to the subwoofer completes the circuit. This relaxes the load on the preamp relative to running two parallel interconnect feeds.

My favorite method is to tap the output of the loudspeaker power amplifier instead. Some subwoofers have a high-level input that can accept the main power amp’s speaker outputs. (Check to make sure this feature is available before purchasing a subwoofer) In this configuration, the amp’s power is not being used by the subwoofer, just its signal. Internal to the subwoofer are high-value resistors that neck-down the amp’s big output to something usable to the sub’s internal amplifier.

The advantage of using the second method is maintaining the sound quality of the power amplifier. As we know, each power amplifier has its own sonic signature. If you use the amp’s output to feed the sub amp, you maintain sonic consistency and improve system synergy.

Remember, the goal of a subwoofer is to extend the low-frequency response of the main loudspeakers. We don’t want to hear the subwoofer. We only want to make believe our main speakers have low-frequency extension (which most do not).

If you’d like to learn more on this subject, WATCH THIS VIDEO I prepared for you.