Understanding subwoofer phase

It seems one of the great mysteries in subwoofer setup has to do with subwoofer phase. Chris helps us understand.

[KingOath]

Q: Where should you set your phase?
A: To where it sounds best

Q: Where should you set your cutoff?
A: To where it sounds best

Q: Whats the best position for my sub?
A: Where it sounds best

Q: Should I buy a ported or sealed sub?
A: Buy the one that sounds best

Q: What frequency should I high pass my main speakers?
A: The one that sounds best

Q: Should I plug my ports when adding a sub?
A: If it sounds best

Q: How should I position my main speakers?
A: Put them where they sound best

Q: How do I know if my system is setup properly?
A: It will sound good

Q: When should I consider upgrading?
A: When it stops sounding good

Peace out folks ✌🏻

[keithbertschin]

Paul’s a legend but it’s good to hear others impart their expertise too

[johnnorris]

Hi Chris I’ve really enjoyed you videos they’re always packed with information and you put your message across very clearly. Great work I’m looking forward to your next contribution 👍

[raphaelmeillat]

Thank you Chris for joining the PS Audio YouTube video family! Very much enjoying the way you go about sharing your wisdom! Would love to get a "cross-over walk-through" from you. I'm sure it would be super insightful!

[bryanjones]

Thanks for explaining why the sub would sound louder due to the sum of the frequency response. Could not find an article or forum that explained why, just stated to choose the one that was the best/louder.

[Maschinenzimmer]

Them curtains on 4K quality are both tripping me out and killing my eyes lol

[ApEsXiT]

Keep up the great content Chris! Lovin it.

[michaelangeloh.]

It's great that you're doubling up on the responses to people's questions. Paul is great to listen to, but we can't let the man do everything. XD
Maybe he should do the more "mythical" questions, as opposed to the more straight-up technical or scientific questions. - Just an idea...

[nb]

Thanks for this great explanation! Could you teach us how to set the sub cutoff frequency accurately (guess it depends on the system also), but generally speaking?

[edgar]

Thanks! A couple of links in the description to the described microphones and software would be very helpful.

[bobnot]

I DSP the heck out of it. I run a MiniDSP 2x4 HD for the subs, two instances of HQPlayer for phase linearization (16k taps each) of both mains and subs, and MiniDSP SHD for PEQ and Dirac Live. A single sub process with a measurement mike and REW: Simulate for the best place for sub, pick a crossover, flatten sub gain with HD, flatten both gains (<300hz) with SHD, flatten both phases with Rephase and HQPlayer, run Dirac Live for stereo with couple of profiles, pick what sounds the best. You will have to take care of delays every step of the way to align the sub with the speakers. Correcting with a FIR filter can present a 80-160ms delay.

[royrice]

You can hear out of phase vs in phase. Your volume and bass will be good in phase and flat out of phase. Positive (red) out of amp to positive on back of speakers. Same with negative. (black). Subwoofer same rules. This has always been the rule that works for me. 👍👍👍

[nononsenseBennett]

I figure an out of phase sub might counteract standing waves leading to a smoother bass note in smaller spaces? Also, out of phase is a type of 'noise cancelling' system

[GoodVibesOnly]

My technique was to walk across the room 400 times trying random combos between my two subs. Landed on each one being almost in opposite phase, 20 and 160 🤷

I did not like where it was loudest, made it boomy and muddy. I went to where they were most quiet, then adjusted gain and low pass from there, then slope. Got me clean bass that hits hard instead of loud bass

[dougbrook]

I need an answer to a question. Hopefully I'll get one. I have an infinite baffle setup on a boat. It uses the engine room as "the box" which is fairly well sealed. If I added a subwoofer in the engine room would it suffer from sound cancelation? Effectively I would be putting a subwoofer in a sealed, or ported box inside of a much bigger subwoofer box. Any thoughts would be appreciated.

[gormyoder]

Jim Smith had a great series of articles on subwoofer setup/optimization (and getting good sound) in your own Copper Magazine:

Look at 14, 15, 16, 17, 18, 19, 20.

Copper 12 The ACK Attack and Un-common Knowledge

Copper 14 Subwoofery: Trick or Treat?

Copper 15 Subwoofery: Trick or Treat? - part 2

Copper 16 Wait A Minute!

Copper 17 Subwoofery: Smooth Operator?

Copper 18 Subwoofery: Location, Location, Location

Copper 19 Subwoofery: The Basics

Copper 20 Subwoofery: The Finale

Copper 22 DPT: Three Critical Steps To Maximize Musical Engagement

Copper 23 ACK Attack is BACK!!

Copper 24 Science vs. Soul

Copper 26 Something to Talk About

Copper 28 The Answer Man

Copper 29 The Answer Man Part 2

Copper 31 More Q & A on Getting Better Sound

Copper 32 Audiophile Therapy

Copper 34 A Dedicated Listening Room

Copper 35 Most Important Component?

Copper 36 EQ, DSP, & You: A Cautionary Tale

Regards,
Gorm

[dnlpnd]

Lovin the speaker-related videos Mr. Brunhaver! Looking for the nugget of knowledge that might make my SPL car louder. :)

[stseely]

Chris you use the term phase. On my SVS SB3000 it has a polarity setting and a phase setting. I can easily see the correct setting for the polarity between the sub and my Buchardt S400 speakers using my omnimic but not sure where to set the phase. I can see the phase setting making a difference in the curve but don't know what is correct.

[Another_Audiophile]

You are becoming a natural mate! Keep it up and your videos rock

[johannjohann]

I always thought you always wanted the correct polarity and everything "In-Phase". Now I'm kinda confused. Unless you have an Isobaric Subwoofer.