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Do I really need a sub? (including REW measurements)

radix

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Ok, I did room sim. I didn't have all your measurements, so I ballparked it. If I slide the MLP and speaker close to the right wall, I get a response somewhat like yours. I truncated the room at 4.75 m to account for the wardrobe.

Screen Shot 2024-01-31 at 2.07.53 PM.png


If I move the speakers and MLP to the left a little, it goes away.

Screen Shot 2024-01-31 at 2.08.16 PM.png
 
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ninetylol

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When you point a sub at a wall and keep it close to the wall, it begins to use the wall like a drum membrane, and it can help spread and improve the bass response, not cancel it.

I saw. your room drawing. You likely need to delay the mains a fair bit. The way its laid out right now I could see it might have a lot of canceling, though it would be good to run the numbers.

You could likely use REW room calculator. Just make it a rectangle along the closet wall and ignore the weird shape by the bed. The cancellations are likely from the bottom wall by wardrobe, if not just directly from the distance between the sub and the mains. 24 Hz is 12.5m wavelength. The sub to wardrobe to couch is maybe 6m, so close to a 1/2 wavelength. I'm clearly ball-parking those numbers, but like I said try the REW calculator pretending it's a rectangular room.

Does the wardrobe have sliding doors or something? You could try hanging a thick blanket in front of it (or have someone hold it) and see how that affects the response.

Personally, I'd try to put the sub behind the couch, or as @sigbergaudio suggested in line with the mains.

When playing around with a sub placement, I like to get a long (5-10m) RCA cable and just string over the floor to experiment with position. The wireless sub transceivers are also great, but you need something to delay the mains.
Thanks i will try putting the sub directly besides the right speaker at the wall tomorrow. May also try the sub behind the couch. (felt a bit irritated last time it was so close to the MLP)

Ive also read some rule of thirds which should reduce cancelations at the MLP most, so in the end i would put the speakers a bit more down into the room (1,67m from wall) and the couch like a fair bit more up into the room (also 1,67 from wall) . This should also improve the stereo triangle. I will play around and post measurements tomorrow night.

Thanks a lot for all the input so far!
 

radix

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Thanks i will try putting the sub directly besides the right speaker at the wall tomorrow. May also try the sub behind the couch. (felt a bit irritated last time it was so close to the MLP)

Ive also read some rule of thirds which should reduce cancelations at the MLP most, so in the end i would put the speakers a bit more down into the room (1,67m from wall) and the couch like a fair bit more up into the room (also 1,67 from wall) . This should also improve the stereo triangle. I will play around and post measurements tomorrow night.

Thanks a lot for all the input so far!

Based on the room sim, if you can move your speakers and couch a bit to the left, maybe even as little as 1m, it might help a lot. Maybe even just measuring the MLP 0.5m to the left.
 

Pareto Pragmatic

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Told you my room is complicated and challenging :p
What makes it very challenging is the restrictions on placement. The room has issues, for sure, but lack of options is always tough. When in doubt, experiment! So here are some things to try.

So pretty much all of my suggestions here are "screw it up in a different way and see what happens!" You might like it better, you might be able to correct it better. Emphasis on might.

Ok, if I were setting things up in this room, I would angle the speakers towards the bed area and angle the MLP as well. Pretty much a corner set up, which would also separate the bed more from the rest of the living space. You MIGHT be able to do this a little. Move the left speaker back 5-10cm/2-4 inches, move the right forward an equal amount. Slide the MLP slightly left and angle it to match. Consider it for a trial, if you think you can live with the asymmetry.

Without that...

My guess is that the bottom right to upper left corner is your main issue. Those are actually double corners, which I have never dealt with, but must be worse than single corners! Given this, I would suggest avoiding pointing any speakers to the right side of the room as best you are able.

Those are for the main speakers, but let me try just focusing on the sub.

For the sub, are you using the "corner" setting? That will roll off the most low bass, wall will do a little less of that, and the third option (in room, center, whatever can't remember but I believe that sub has three setting) will roll off the least bass. So first try at the side wall, try pointing it at the opposite wall then the near wall. Try corner setting and the in room setting for both.

Then try this. Set sub to in room/center. Leave it where it is. Point it to the left side of the wardrobe near your bed. Try to line up the first reflections so they go into the bed nook.

After that, point the sub at the left wall at a slight angle, with the second bounce off the right wall directed towards the bed nook.

Straight at side wall, one bounce to the bed, two bounces to the bed. You should see some variation in measurements. I think that will bracket your options with this position and sub, and if one of those does better than the others, you can dial it in a bit with some minor angle shifts.

For me, I would go with the sub and current set up and enjoy more texture and detail on drums and bass, because that dip at 60 would annoy me greatly. But for Deadmaus? I doubt I would notice a difference that mattered to me, and so would likely use that sub money on something else.

Good luck, and remember that the only thing that matters is that you like the sound in the end.
 
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ninetylol

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Ok so tldr I ditched the sub

I tried a lot of stuff and got more and more frustrated with the sub. Most of the times i had phase issues and big resonances. On the bright side I found a MLP (not so different to before) which has -3db at 25Hz with speakers only. Did some heavy EQ to remove resonances and it sounds like a night and day difference now.

Thanks for all your thoughts and impressions, but seems in this room sub is not for me.

Here are my final results with speaker only NO EQ vs PEQ
Screenshot 2024-02-01 202416.png
 

radix

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Ok so tldr I ditched the sub

I tried a lot of stuff and got more and more frustrated with the sub. Most of the times i had phase issues and big resonances. On the bright side I found a MLP (not so different to before) which has -3db at 25Hz with speakers only. Did some heavy EQ to remove resonances and it sounds like a night and day difference now.

Thanks for all your thoughts and impressions, but seems in this room sub is not for me.

Here are my final results with speaker only NO EQ vs PEQ
Not too bad. Glad you were able to find a configuration that works for you. 3 cheers for a measurement mic and rew.
 

ooheadsoo

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Well, it sounds fine, but at my listening volumes at around 60db theres really like no difference at all with sub or without for most (99%) songs. So its really more a problem if its worth the bucks. If i turn up the music to 80db, theres more of a difference but 1. I cant listen so loud with neighbours around and 2. I would do so very rarely.

I think a lot of songs go down to like 50-40 Hz, where a sub totally makes sense but seems my speakers already go down as low.

So in the end its probably a philosophical and financial question, if I want to keep the sub or not. I think in another room it would make a bigger difference.
Sad to say, but at 60db, even if you had subwoofers that went down to 10hz, you probably couldn't hear it much. I don't know the exact research on it, but this graph suggests that you need to get to about 80db to hear 20hz.
1706897396943.png
 
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