Subwoofer Phase and Polarity | When & Why to Adjust

[@m.m.3753]

Really your are the best. Sad i am So far away from you. Please make more Videos. Its So easy to understand your explenation. THX

[@HomeTheaterGamer]

Thank you! I really appreciate that!

[@tallpaull9367]

try this Manual Phase Setup Method: - let your speakers play full range (ie: mine play down to 50Hz) - set crossover on sub to 10Hz above (ie: mine 60Hz) - Play some music with bass, adjust volume so Sub is noticeable but not too loud - play the lowest frequency of your speakers (ie: mine 50Hz tone). can download a free tone generator app for phone or computer…) - use SPL meter ( or smartphone with SPL meter app works). I use settings C-Weighted, Fast, Low on SPL meter) - cycle through Phase settings (typical 0, 45, 90, 135, 180, 225, 270, 315) and look for the lowest SPL level = Null Point - if Null Point is 0-180 then add 180 = your Phase setting. if Null Point is 181-359 then subtract 180 = your Phase Setting. - now you can play with your Crossover settings (ie: Speakers set to 70 Hz, Subwoofer to 80 Hz. etc…) If Dual subs are both in front like in this video, use this method to setup each subwoofer individually (or just use the same setting). If running one sub on front wall and one sub on rear wall then flip phase 180 degrees from the setting you determined on front sub. (ie: if front sub 135, then rear sub 315) It would be interesting to to see what would happen if you did this setup then ran your Room Correction. But I would assume setting Phase to 0 would be best.

[@tonytramonti5828]

I’m polish and I design speaker, I designed the phaseless Kurvatech 7600 using biliach amps, best sub goofer in world , like betman

[@ptipete]

With a two subwoofers system, do both subs need to have the phase set to normal, or could one be set to reverse? An audio signal is alternating current so I'm wondering if a 2 sub system can cover the entire sine wave of a signal and get a bigger punch!

[@dottorfoggy]

Must be the mini DSP the hd version? Or will work the base 2x4 as well?

[@davethestalker]

Very informative, I’m constantly playing with my phase switch, and distance and sun volume levels. I’m never satisfied. Are you obeying Audyssey telling us to set the subs at -75? Den-in x7200wa owner.

[@mskmsk7174]

Excellent practical channel

[@TyGamer125]

I did go miniDSP route with my x1400h, still in the process getting them perfected. Also going to try using Multi sub optimiser.

[@HomeTheaterGamer]

Yeah. There is a definite learning curve and since I’m one who likes to experiment and tweak, it would be a 2-3 day process for me haha. I’d enjoy every minute of it though, I’m sure!

[@radar895]

Is there an app you can use to do what you are doing ?

[@welderfixer]

A time alignment DIY how-to video that is an accurate step by step using REW and a Dayton Audio DSP-LF like I am using. PLEASE! I'll make the popcorn.

[@HomeTheaterGamer]

I'll have to look into the Dayton Audio DSP-LF. I've heard of it before but have never really considered it or looked at the features.

[@welderfixer]

@@HomeTheaterGamer Brad, take a look at our friend 123Toid's review of it. Especially, before ordering. Gotta get extra parts with it.

[@davethestalker]

I had asked this in a different video. When using mixed subs, does Audyssey EQ the weaker of the two subs? I’m talking about native Audyssey on the AVR, not the app.

[@HomeTheaterGamer]

I believe on systems with Audyssey’s MultiEQ XT, it will just EQ the summed response of both subs, not the lesser of the two. That’s due to MultiEQ XT receivers way it handles dual subwoofer outputs (it’s basically a Y-splitter inside the receiver, and you only have a single subwoofer trim level and distance setting). However, if the receiver has MultiEQ XT32, it will EQ each sub individually and try to achieve a flat response when both subs are playing. In that instance, it may actually cause some issues if you have a weaker sub, but I can’t be sure as I don’t currently have a receiver with XT32 on it (working on getting one from my contact at Sound United). I may have the Director of Software Engineering from Audyssey in a video at some point in the future and I think this would be a fantastic question to have him answer as well, since he literally knows the ins and outs of Audyssey itself.

[@davethestalker]

@@HomeTheaterGamer I agree with this because the sweeps are using both subs together. The only time the subs are separated is the first sweep in the main listening position to establish distance. I have thought this for years that I’ve had dual sub AVRs. The reason I’m asking is because I posted a question on AVSForum recently about dealing with my 5 sub system in the Denon AVR-x7200wa thread. One of the more knowledgeable people answered with the idea of Audyssey only EQ’ing the lesser of the two subs. I have a very complicated system using a PB1000 Pro, Polk PSW-505, two Def Tech Pro Cinema 60 subs, and each of my Paradigm Monitor 90p has two 8” powered subs. I have my system in a basement that ideally needs a pair of PB3000 or 4000 lol. I can’t afford that, so I’m using what I have. Currently, only Sub 1 is being used for LFE from the SVS. The Paradigms are getting L/R pre-out so I can utilize the gain and frequency controls. The Def Techs are tapping into the speaker terminals of the respective L/R. The Polk is tapped into the bottom set of each L/R for signal. When I run Audyssey, I have to turn off the subs in the front, otherwise Audyssey will kill the bass to the mains. I have the frequencies set at 60 for the front. The SVS is behind me, basically in the middle of the room. When I first got the SVS, I tried it in the front and it just isn’t strong enough to pressurize the room. Until I get some heavy curtains to divide the room, this is the best I can do with my space. I have a laptop coming soon, so I’ll be able to use REW and the PEQ in the SVS app.

[@sbonamo]

The reality is - most low frequencies are mono so each individual sub's output is somewhat irrelevant, it's the combination of the mains + your subs that needs to be optimized. Secondly - I would be cautious of tools like Audyssey because a) boosting nulls is virtually impossible (you're dumping more and more energy into a dip in the wave irrespective of amplitude) and b) the human ear doesn't hear the way REW or any tool. As such, we don't hear the intricasies being shown to be corrected in the video. Net - you may do more damage than good.

[@davethestalker]

@@sbonamo timing with multiple isn’t irrelevant. It’s crucial to get it correct.

[@sbonamo]

@@davethestalker where did I say timing is irrelevant? I said each sub's mono output is less relevant due to low frequencies that humans cannot localize. Of course, timing (phase) is relevant.

[@uceddiemo]

The obvious next step would get the Mini DSP and share what you’ve learned

[@bpali2001]

Hey! Whats the outro song?

[@michaelmilkovich4120]

how you able to tell what channel your making worse?

[@trishpipkins]

I think we're keeping the subwoofer. I don't need to save for a new car right now anyway. 😂

[@HomeTheaterGamer]

Wait a second... You drive? 😀