Time and Phase alignment of SPEAKER and SUBWOOFER using REW

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[kapooranuj]

Hey Dr Sound!
Besides the long pending sub integration... A detailed REW video is really really needed.. Please.

[adrianadrianp]

Be amazing to see a video walking through alignment using REW with a more detailed explanation as you look at graphs etc

[Zachary_Setzer]

I'll keep saying it until you do it: a lot of us would be willing to pay a pretty penny for a full-blown audio calibration course. Just write and record it during your ample free time. 😂

[MrBonger]

Yes, please do a video on proper subwoofer integration 😊

[pulDag]

I was asking that myself for years. Thank you Matt

[jglaserbot]

Thank you as always for your information. I’ve recently purchased some Rel subs and John Hunter of Rel discusses alot about their Rel 3D system which is supposed to be a take on Ray Dolby’s vision of having full range speakers 20-20K Hz for theater. Rel’s basic concept is using three subs minimum, which consists of 1 sub for the mains and 1 sub for the rears using their high level connection along with the LFE connection and then the third sub would be located near the center speaker hooked up high level only. I’m curious to your thoughts on this as I understand the concept they’re trying to do but the implementation of getting it all to work seamlessly seems daunting.

[mikeortiz]

Being a visual learner, are there any example videos you could point me to or would a part II with screenshots be possible? Thanks.

[nowayman]

On fire with your post consistency!!! Super appreciated as always learn something new 🤘

[TheLkdude]

Given your expertise and the need to be mindful of time, I encourage you to provide explanations that are both useful and valuable. This isn't a criticism—just a request! As you can see below, there is a strong demand for this content. It could be helpful to consider a demonstration or, at the very least, a visual explanation to enhance understanding.

[BobFrostV]

This is the best content 😆
But, I know everyone can't handle it lol

[shaneb]

Have you investigated or tested A1 Evo with Audessey yet?

[ChadAV]

I have never used the spectrogram in REW but I'll check it out. Thanks. I have been just using the alignment tool to impulse align the sub to my center and then I use AP filter to fix around the xover point.

[davidjalsoviczky]

Thanks again for this great video. When you mention the Alignment tool in REW, there are 2 options, Phase alignment and Impulse alignment. You are talking about the Phase alignment, right?

[steakhoux]

I also had those problems. My MSO optimized array has different group delay than my mains below 70Hz. My solution was to raise the XO frequency to circumvent this area and have the XO where GD was more similar. If possible it can also be helpful to use 48 db per octave filters so that proper phase alignment only has to be +- 0.5 octaves around the XO. All pass filters are really helpful especially because you can use them for each channel. It would be nice if Trinnov would add them in the PEW section. :)

[kewlbug]

The processor in my car uses an All Pass with a Q of 1 for the adjustable phase, the 180 point on the adjustment centered at the crossover point. moves the Allpass up and down to correlate with the indication, and moves with the crossover if you change that. I would assume these home units are doing similar.

That said, I almost never ever touch it. I will time align the slopes using both the 0 and the 180. whichever one makes the most sense for the distances and response is what I go with. And usually matches slope over the longest bandwidth. (Level phase at cursor button extremely helpful) I DO need to utilize the spectogram more. Just to check my work really.

The allpass/active phase adkustment, might be more helpful if you have Smaart or similar to watch the changes live. Otherwise its a guess and check process...

[welderfixer]

Anyone else also think "The more I learn about home theater setup, the less I want to do it."? Just run Room Correction, open a beer and try to enjoy a movie. The more you drink the better the system sounds. HAHAHA!
Anyway - Thanks Matt!

[simpsonbergman]

Thanks! Thanks for your input on my question!
I have another one:)
What I'm finding is that no single time delay gives a great match between the two impulse responses. Due to the duration of the impulse response, I can set the relative delay so that the first half of the impulse responses match very well, but the second half of the impulse responses are then out of phase. (I'm looking at the impulse responses at particular frequencies.) I understand that this implies a need for a more involved filter, e.g., allpass filtering. Do you have an opinion about Dirac bass control for this? [I am using a minidsp flex for stereo with 2 subwoofers. Dirac bass control is not available for Minidsp. I'm thinking of bringing a computer into the system to run Dirac with bass control, and getting a four channel DAC to then feed the 2 speakers and 2 subwoofers. I originally wanted to avoid using a computer, but I'm now considering it. I don't really want to get an AVR since I already have a hypex stereo amplifier and an AVR with Dirac license is quite expensive and I guess overkill for a stereo-only audio system.] (Sorry for the lengthy question!)
By the way, REW lists 3 different wavelets. I try teach one, they give quite similar results, but do you have a preferred wavelet?

[gbye]

Where's the wavelet feature in REW? I found it - it's a mode within the Spectrogram tool. It would be sueful to have a talk on what this tool is showing us.

[tomashelland]

At least show us on your pc how you get this right🤣 some of us need to see it, to get it🙈 sadly😂

[MilGrip]

Details, shmetails... just use the "squat and nod" method as a certain alphabet company uses, they sell really expensive stuff... so it must be right, right?😅