Set Phase 0 or 180 on the sub?

Gizmo99

Not sure what setting to set on my sub. 0 or 180? Both sound about the same. But I was reading a customer review on LSI15 from polkaudio.com that I should set the phase on my sub to 180 if I am paring it up with the LSI15

Any advice is appreciated.

Thanks

Face

Whatever sounds better. The only way to know for sure is with test tones and a SPL meter.

dustradio

Tried Them Both With The Results You Descrbed. I Cant Tell Any Differance! 30.30 Standing By

Erik Tracy

Hmm - not sure what else to suggest here.

When I first set up my sub, I tried both 0 and 180 as well.

At first I had to listen carefully - because I could "hear" the bass in either position, but ended up going 0 as I noticed that the overall sound was "full" from top to bottom.

Hard to describe - but with the 180 setting - there seemed to be a hole in the sound spectrum. Sure, the bass seemed there, but it just felt like there was a full wall of sound feeling from top to bottom when set at 180.

Have another try at a listening test.

Cheers

wingnut4772

Erik Tracy wrote: »

Hmm - not sure what else to suggest here.

When I first set up my sub, I tried both 0 and 180 as well.

At first I had to listen carefully - because I could "hear" the bass in either position, but ended up going 0 as I noticed that the overall sound was "full" from top to bottom.

Hard to describe - but with the 180 setting - there seemed to be a hole in the sound spectrum. Sure, the bass seemed there, but it just felt like there was a full wall of sound feeling from top to bottom when set at 180.

Have another try at a listening test.

Cheers

Trying the sub alone will not give you the same results as trying the phase as it plays with your other speakers. Its all about the timing and cancellations with the other speakers...


Get some bass heavy movies and replay scenes while adjusting the phase and see which sounds better. It's preferable to have another turn the knob while you are in the sweet spot if you can find a volunteer.

ShinAce

Take a "AA" battery and connect the positive to the positive on the subwoofer terminals(I assume you can get between the sub amp and speaker wires), then do the same test on the mains. If both woofers 'pop' outwards, the set the phase to 0. If one pops out and the other pops in, then set the phase to 180.

Otherwise, find some material that's mostly bass around the crossover frequency and use the phase setting that gives you the loudest overall response.

Face

ShinAce wrote: »

Take a "AA" battery and connect the positive to the positive on the subwoofer terminals(I assume you can get between the sub amp and speaker wires), then do the same test on the mains. If both woofers 'pop' outwards, the set the phase to 0. If one pops out and the other pops in, then set the phase to 180.

That isn't always true. Placement can affect this.

Erik Tracy

wingnut4772 wrote: »

Trying the sub alone will not give you the same results as trying the phase as it plays with your other speakers. Its all about the timing and cancellations with the other speakers...


Get some bass heavy movies and replay scenes while adjusting the phase and see which sounds better. It's preferable to have another turn the knob while you are in the sweet spot if you can find a volunteer.

Never said just the sub alone - sorry my bad if that's the way it came across.

I meant to say WITH your fronts

wingnut4772

Erik Tracy wrote: »

Never said just the sub alone - sorry my bad if that's the way it came across.

I meant to say WITH your fronts

Oh OK. Well carry on....:)

Ron Temple

Generally, if the sub is in the front soundstage, 0 will put you in phase with your speakers. If the sub is located elsewhere, then adjusting the phase might be beneficial.

organ

Erik Tracy wrote: »

Hmm - not sure what else to suggest here.

When I first set up my sub, I tried both 0 and 180 as well.

At first I had to listen carefully - because I could "hear" the bass in either position, but ended up going 0 as I noticed that the overall sound was "full" from top to bottom.

Hard to describe - but with the 180 setting - there seemed to be a hole in the sound spectrum. Sure, the bass seemed there, but it just felt like there was a full wall of sound feeling from top to bottom when set at 180.

Have another try at a listening test.

Cheers

+1 Took me a while and I hear the same thing. I think the "hole" you described is the result of frequency cancellations. The sound wave from the woofer cancel when they meet the opposite wave from the speakers.

zingo

Phase is pretty important when playing with multiple subwoofer that face each other, or any speaker that faces subwoofers because you get canceling effects and other weird things. A good thing to think about is if you have two subs facing each other, the waves would be hitting each other and be destructive. However, if you turned the phase on ONE of the subs, then they would be outputing waves in the same direction.

gtaudio

zingo wrote: »

Phase is pretty important when playing with multiple subwoofer that face each other, or any speaker that faces subwoofers because you get canceling effects and other weird things. A good thing to think about is if you have two subs facing each other, the waves would be hitting each other and be destructive. However, if you turned the phase on ONE of the subs, then they would be outputing waves in the same direction.

I know this is a very old post but I am curious if this is true. Would it be beneficial to have two subs one in phase and one out of phase?

I have two subs both on the front stage in line with RL and C speakers. I am guessing phase at 0 makes sense in this setup.

cristo

gtaudio wrote: »

Would it be beneficial to have two subs one in phase and one out of phase?

definitely NO.

steveinaz

Generally if the subs are on the same wall as the mains, you would want 0 selected; but you should "verify" with bass-heavy material. Whichever setting renders the most bass with your mains is the correct setting. Then re-adjust your level to get the smoothest curve.

unc2701

cristo wrote: »

definitely NO.

Actually, depends on room, placement, frequency and listener position. For example, if the subs were 1/2 wavelength apart in distance, they'd cancel when set to the same phase.

Only way to do this is to listen to the response and choose what sounds best to you.

Syndil

Don't need an SPL meter to test for phase. If you have a DVD with the THX Optimizer on it, it will have a subwoofer tone sweep that you can use to verify the phase on your sub is properly set. If it is out of phase, then there will be a gaping null at the crossover point between your mains and your sub. If the phase is properly set, the sweep should be fairly smooth with no nulls.

Phase is not something that someone can simply tell you what the answer should be--you have to test and find out. And yes, if you have two subs, you need to test each individually to determine the proper phase setting for each. They may not match.

Lietuvis91

steveinaz wrote: »

Generally if the subs are on the same wall as the mains, you would want 0 selected;

I find this to be true from my experience too. I set up subs with first setting phase to zero and slowly increase phase until it sounds blended in right. My current phase setting is close to zero on my HT system. I find it to be the best setting, especially for music.

Erik Tracy

I've got my mains and a single sub on the same wall - after much agonizing experimentation and listening - I've got my sub set on 180 phase.

Lietuvis91

Erik Tracy wrote: »

I've got my mains and a single sub on the same wall - after much agonizing experimentation and listening - I've got my sub set on 180 phase.

Very interesting. I guess it all depends on the sub. What sub(s) are you using?

Erik Tracy

Lietuvis91 wrote: »

Very interesting. I guess it all depends on the sub. What sub(s) are you using?

Epik Valor (sealed)

I'm odd....I know....but imo, its all about ears on for what sounds 'best'...and your ears may be different than mine

Lietuvis91

Erik Tracy wrote: »

Epik Valor (sealed)

I'm odd....I know....but imo, its all about ears on for what sounds 'best'...and your ears may be different than mine

Oh, I'm totally with you, your ears are the ones that matter! I do think it has also a lot to do with the subs design and resulting acoustics due to location in the room. I moved my sub around a lot before i settled on a spot and the volume and phase setting had to be adjusted significantly based on the difference of the subs location. There definitely is no magic setting that is always right.

steveinaz

The problem with using your hearing, is that you may select a setting that isn't properly phased to the mains. It's like calibrating an HDTV, either you do it right or you don't--the choice is yours. The phase dial is for "syncing" the subs woofers with the mains, that's why after you reach the setting that produces the most bass (all woofers "singing" together)--you go back and do your sweeps again to correct your level for a nice waveform. (if needed).

Now, if you happen to "like" slightly out-of-phase bass, then disregard.

My comment about being on the same wall did include the word "generally"; because sometimes phase will need to be tweaked, even in that circumstance, but it's not the norm. As with everything, do your measurements---I know it's a PITA, but you'll be rewarded with a well integrated sub(s) when you're done.

"Graphing" your sub will sometimes expose a blatant phase issue as well.