So your current subwoofer went out or you’re planning to upgrade to a new model? The chart included here shows the phase responses of the Hsu VTF-15H subwoofer in sealed mode (green trace) and the Sunfire CRM-2 speaker (blue trace) in the crossover range, between 60 and 200 Hz.. Subwoofer Phase Switch: Normal vs Reverse. 1. Home theater enthusiasts have it easy because every A/V receiver or surround processor made since about 1996 has a built-in subwoofer crossover that filters the bass out of the main speakers and the mids and treble out of the sub. This affects the "phase" of the sound wave. For example, complex phase relationships between mics on a drum kit can smear transients. Active vs. THe front soundstage via the two front speakers wont be centred correctly. Listen For Thin Bass: Firstly, phase cancellation is most apparent in low-frequency sounds, especially at or below the crossover frequency. So what is phase? This can help the kit blend better and sink back into the mix, instead of sitting right on the front plane of the speakers. You can also access more phase tests here: Online Stereo Polarity (Phase) Sound Test Note that out of phase wiring cannot damage either the speakers or the amplifier. The tl;dr version. Set phase of the subwoofer to make the sound have the widest audible range of frequencies. Note how even within this narrow range of less than 2 octaves, the phase of each one changes a lot: 154° for the Hsu and 114° for the Sunfire. Normal: keeps the polarity (+/-) of the Sub the same relative to the rest of your speakers. Passive Subwoofers Subwoofers come in two varieties: passive and active. This essentially puts the sub 180 degrees out of phase. If the subwoofer is out of phase with the speaker channel being tested, partial cancellation of some frequencies will occur and the sound will tend to de-emphasize some frequencies in the test tone. When it comes to phase, a blanket fix-all approach isn’t always appropriate. Read on to find out about different types of subwoofers—and their pros and cons—as well as their setup, placement, and integration. So how do you tell if your subwoofer is out of phase? You want to know the exact measurements… It is impossible to do this alone. In that case, you’d want to save some cash by using the existing enclosure instead of buying a new one.This brings in the need to measure the subwoofer. A passive subwoofer is just a woofer or woofers in an enclosure that must be driven by an external amplifier. Adding delay to the subwoofer signal can sometimes help the subwoofer to integrate better with the loudspeakers in the room. Did you know that if your speakers are out of phase the sound quality is affected massively - bass is reduced significantly and stereo imaging is lost. You want to set the phase so that the sounds coming out of your sub don't cancel out the sound coming out of your other speakers. So the phase switch determines whether it moves in first or out first. The phase control in a powered subwoofer allows the user to add electrical delay to the incoming signal. To check your sub's phase, play music with lots of bass, listen for a minute or so, and have a friend sitting by the sub flip the sub's 0/180-degree phase switch slowly back and forth. Speakers are out of phase if the wires for one of your speakers are connected the wrong way around. When a sound starts to come out of the speaker, it moves in first or out first. Phase cancellation can also create depth. Out of phase speakers lack bass and audio tends to lack body when played out of phase. Setting the phase control to 180 degrees reverses the polarity of the subwoofer. In two-channel, almost no preamps or integrated amps have built-in subwoofer crossovers. The phase control operates over a range of 0 to 180 degrees. Reverse: flips the polarity (-/+) of the Sub relative to the rest of your speakers.