Normal: keeps the polarity (+/-) of the Sub the same relative to the rest of your speakers. In two-channel, almost no preamps or integrated amps have built-in subwoofer crossovers. 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. Reverse: flips the polarity (-/+) of the Sub relative to the rest of your speakers. The phase control operates over a range of 0 to 180 degrees. Phase cancellation can also create depth. The phase control in a powered subwoofer allows the user to add electrical delay to the incoming signal. THe front soundstage via the two front speakers wont be centred correctly. So what is phase? Out of phase speakers lack bass and audio tends to lack body when played out of phase. 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. This affects the "phase" of the sound wave. Set phase of the subwoofer to make the sound have the widest audible range of frequencies. This can help the kit blend better and sink back into the mix, instead of sitting right on the front plane of the speakers. 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.. It is impossible to do this alone. 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. A passive subwoofer is just a woofer or woofers in an enclosure that must be driven by an external amplifier. This essentially puts the sub 180 degrees out of phase. 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. So the phase switch determines whether it moves in first or out first. 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. 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. Listen For Thin Bass: Firstly, phase cancellation is most apparent in low-frequency sounds, especially at or below the crossover frequency. You want to know the exact measurements… Setting the phase control to 180 degrees reverses the polarity of the subwoofer. When a sound starts to come out of the speaker, it moves in first or out first. 1. Active vs. 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. So how do you tell if your subwoofer is out of phase? Adding delay to the subwoofer signal can sometimes help the subwoofer to integrate better with the loudspeakers in the room. 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. Speakers are out of phase if the wires for one of your speakers are connected the wrong way around. Read on to find out about different types of subwoofers—and their pros and cons—as well as their setup, placement, and integration. When it comes to phase, a blanket fix-all approach isn’t always appropriate. For example, complex phase relationships between mics on a drum kit can smear transients. The tl;dr version. Subwoofer Phase Switch: Normal vs Reverse. So your current subwoofer went out or you’re planning to upgrade to a new model? Passive Subwoofers Subwoofers come in two varieties: passive and active.