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

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ninetylol

ninetylol

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Have you tried adjusting the sub phase or inverting it? You can also try elevating the sub or pointing it towards a wall or sideways. It's all geometry at those frequencies.

The sub is doing it's job for the 60 Hz null. It's the 24 Hz one to tackle.
Yeah I tried. Inverting the phase made everything worse. I think i need some delay settings for the sub/speakers, but its not included in WiiM Software yet.

Can i really point a sub at a wall without a lot of distance (say 5cm)? Is there enough space so freuqncies spread and doesnt cancel itself back from wall reflection? Seems like the intuitive thought.
 

sigbergaudio

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I see some people suggesting you should let the mains run full range. Based on the graphs I see no reason to do so. The sub fills out your dip at 60hz, and you have a more even response. You now also have more headroom / less distortion in the bass range since you've high passed the mains.

Due to the null at the very low end you don't have much more bass extension than you used to have, but since you already had extension to 30hz, you wouldn't have noticed much difference either way.

As you pointed out yourself, you won't really get more bass without turning up the volume, which isn't necessarily desirable if you want a neutral sound.

So what exactly were you expecting to achieve beyond this when you purchased the subwoofer / what problem were you trying to solve?
 
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Sancus

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I see some people suggesting you should let the mains run full range.
People parrot this because Geddes said it in a pdf or maybe in a video, I can never remember. The documentation of his advice is terrible. It makes more sense when you understand he was talking about specific setups with truly gigantic sealed woofers(15", as I recall).

It's a pretty bad idea with little ported bookshelves.
 

Sokel

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People parrot this because Geddes said it in a pdf or maybe in a video, I can never remember. The documentation of his advice is terrible. It makes more sense when you understand he was talking about specific setups with truly gigantic sealed woofers(15", as I recall).

It's a pretty bad idea with little ported bookshelves.
Kef repeated that to a user's question in another thread couple of months ago,it's not only Geddes.
It seems like a popular advice even amongst the ones that know stuff :confused:
 

Pareto Pragmatic

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Can i really point a sub at a wall without a lot of distance (say 5cm)? Is there enough space so freuqncies spread and doesnt cancel itself back from wall reflection? Seems like the intuitive thought.
I'm no expert, but I have faced a similar issue.

Think pointing at the other wall. I've had improvement on a similar bad node by going with a sub between my speakers (not centered but between), and pointing it at the far side wall. In your case, with an almost square room, probably won't help as much as it did for me. But give sideways a try.

Also, you can try different angles on the sub between 0 (straight out) and 90 degrees (side wall). That MIGHT shift your problems to give you more at 20hz. But other problems will happen if that works for 20. Try 75 degrees then 45 to start, see how those changes affect things. Free and fast to check.

My guess is that your corners are the problem, so making sure speakers/sub are not pointed directly at ANY corners will be worth trying. To make things not as bad, not to fix the problem.

I do think getting 60hz up is worth the sub, there are a lot of bass notes there. Listen for a while and you'll notice it more and more.
 
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ninetylol

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I see some people suggesting you should let the mains run full range. Based on the graphs I see no reason to do so. The sub fills out your dip at 60hz, and you have a more even response. You now also have more headroom / less distortion in the bass range since you've high passed the mains.

Due to the null at the very low end you don't have much more bass extension than you used to have, but since you already had extension to 30hz, you wouldn't have noticed much difference either way.

As you pointed out yourself, you won't really get more bass without turning up the volume, which isn't necessarily desirable if you want a neutral sound.

So what exactly were you expecting to achieve beyond this when you purchased the subwoofer / what problem were you trying to solve?
I ordered a umik 1 with the sub, so i didnt know my Bass extension was already this low. From DBR62 measurements it seems the rolloff is at about 65 Hz, but seems my room extends this quite a lot. As I said its not really a big (to none) difference when you actually listen to music.
 

Pareto Pragmatic

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People parrot this because Geddes said it in a pdf or maybe in a video, I can never remember. The documentation of his advice is terrible. It makes more sense when you understand he was talking about specific setups with truly gigantic sealed woofers(15", as I recall).

It's a pretty bad idea with little ported bookshelves.
It's a pain to do for any speakers. At least compared to dialing in with a crossover.

And done right, the room is still the room, and those DBRs are going to be struggling with the lows and give more distortion in the bass. So best case, worse sound.
 

Willem

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The sub is doing very well to smoothen the response down to your big null around 24 Hz. With a null there is no point in raising the level, either with more amplifier power/equalization, or by adding a single sub. The problem is the room, and the only option is an (additional?) subwoofer in a radically different location that you have not yet tested. Of itself, this subwoofer should be more than enough to produce pretty deep bass. In fact, it does, below the null.
 
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sigbergaudio

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Can i really point a sub at a wall without a lot of distance (say 5cm)? Is there enough space so freuqncies spread and doesnt cancel itself back from wall reflection? Seems like the intuitive thought.

Yes and yes.
 

sigbergaudio

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I ordered a umik 1 with the sub, so i didnt know my Bass extension was already this low. From DBR62 measurements it seems the rolloff is at about 65 Hz, but seems my room extends this quite a lot. As I said its not really a big (to none) difference when you actually listen to music.

So are you now currently happy with the bass performance of your system? Or not? What is perceived as the problem?
 
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ninetylol

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So are you now currently happy with the bass performance of your system? Or not? What is perceived as the problem?
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.
 

Willem

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The room is your problem. It is almost square, and the horizontal dimensions are almost exactly twice the height. However, even so the sub does a pretty good job improving the 30-90 Hz response.
 

Digital_Thor

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People parrot this because Geddes said it in a pdf or maybe in a video, I can never remember. The documentation of his advice is terrible. It makes more sense when you understand he was talking about specific setups with truly gigantic sealed woofers(15", as I recall).

It's a pretty bad idea with little ported bookshelves.
Yeah... but he also clearly state, that closed woofer constructions is optimal for his version of blending the mains with the woofers, since you get minimum phase issues and 2 extra bass sources, leaving you with a larger area to have smooth even bass - in typical "small" living quarters.
If you just want to sit one place, then we can be a bit more flexible - again a compromise - which you may or may not like or even hear.

The reason he uses 15" drivers is simply to make it work with his waveguides and to have a driver capable of playing with no high pass filter at his wished SPL, which ease up integration - IF - you do not have a specific placement of your subwoofers right next to your mains. Because then we are talking about something that resemblance a 3 way of some sort. One of the main points of having the sub and mains separate, is to take advantage of the physical placement optimal for subwoofers, and then keep the mains optimal placed for stereo - exploiting room acoustics for even and smooth bass.

Of course there are compromises, but I've tried them all, and there is actually no real wrong here, rather than the importance of the individual to face the compromises that we are willing and unwilling to make.

Sorry for not seeing that the mains were ported - my mistake. Nevertheless, I did make a sub integrate pretty well with a small set of ported B&W speakers once, so even though a compromise, there should be a chance of an ok result anyway IMO.

To the OP:
1. What is your amplification for the ELAC? Any DSP there?
2. Could you draw your setup/room? - just sketch in hand and take a picture with rough measurements of placement. also the materials the room is made of.
3. Do you have any specific requirement when it comes to the look and placement of any of your speakers/subwoofer - aesthetics?
 
OP
ninetylol

ninetylol

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Yeah... but he also clearly state, that closed woofer constructions is optimal for his version of blending the mains with the woofers, since you get minimum phase issues and 2 extra bass sources, leaving you with a larger area to have smooth even bass - in typical "small" living quarters.
If you just want to sit one place, then we can be a bit more flexible - again a compromise - which you may or may not like or even hear.

The reason he uses 15" drivers is simply to make it work with his waveguides and to have a driver capable of playing with no high pass filter at his wished SPL, which ease up integration - IF - you do not have a specific placement of your subwoofers right next to your mains. Because then we are talking about something that resemblance a 3 way of some sort. One of the main points of having the sub and mains separate, is to take advantage of the physical placement optimal for subwoofers, and then keep the mains optimal placed for stereo - exploiting room acoustics for even and smooth bass.

Of course there are compromises, but I've tried them all, and there is actually no real wrong here, rather than the importance of the individual to face the compromises that we are willing and unwilling to make.

Sorry for not seeing that the mains were ported - my mistake. Nevertheless, I did make a sub integrate pretty well with a small set of ported B&W speakers once, so even though a compromise, there should be a chance of an ok result anyway IMO.

To the OP:
1. What is your amplification for the ELAC? Any DSP there?
2. Could you draw your setup/room? - just sketch in hand and take a picture with rough measurements of placement. also the materials the room is made of.
3. Do you have any specific requirement when it comes to the look and placement of any of your speakers/subwoofer - aesthetics?
1. WiiM Amp with PEQ but no delay settings

2. Walls are pretty thin to the right, but massive to the left.
Unbenannt.jpg


Told you my room is complicated and challenging :p

3. I cant change the orientation, i can just set the couch and/or TV Board with speakers lower/higher and more left/right. (which both didnt change the response a lot)

Btw closing the door doesnt make a lot of difference. I also had the sub at the bottom right corner, but it felt a bit too close to the MLP with similar response.

Thanks!
 
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LSPhil

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You take your subwoofer and place one or both satellites on it. You close the port in both satellites. Then you increase the crossover frequency of the subwoofer from minimum until you find a nice effect. Once you're happy with that, counter-phase and listen for cancellation.

If you are happy, place the subwoofer on your chair where you listen to music. Have music playing and walk around your room and listen to where you like the bass best. There is space for your subwoofer.
 
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DJBonoBobo

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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.
You are the only one who can answer the question if the sub is worth it and if you want it.
But personally i think your room and your example is more or less a best case scenario: The sub seems to works very well, not in the inaudible (with 60-65dB) super low area, but in the much more important 60Hz area. It frees the speakers from low frequencies where they have a lot of problems in your room anyway. In the end you have a pretty good bass FR overall.
If this is still not really audible i don't think a different room or different positions change this. I don't know, but i think it doesn't get much better for your use case. Maybe your expectations are too high?

I don't really understand most of the suggestions here. What is their goal?
 

Digital_Thor

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1. WiiM Amp with PEQ but no delay settings

2. Walls are pretty thin to the right, but massive to the left.
View attachment 346448

Told you my room is complicated and challenging :p

3. I cant change the orientation, i can just set the couch and/or TV Board with speakers lower/higher and more left/right. (which both didnt change the response a lot)

Btw closing the door doesnt make a lot of difference. I also had the sub at the bottom right corner, but it felt a bit too close to the MLP with similar response.

Thanks!
First off, if you actually like your setup, then enjoy it and use some time to fiddle with the last details if there is something that truly annoys you.
If you still want to try different things, then read on. But as others pointed out, maybe you already have close to what you can achieve with the current setup.

Great drawing :) Just to try, you could put the subwoofer way in the left corner.... even though I know the signal wire would be quite long.
I can't make out the filter settings of your amp from the manual. It mentions a built-in EQ on both the input and output. Because what I do, is to do EQ on the mains, the subs, and then on the input, so that the final EQ after the mains and subwoofers work optimal together I then use the input EQ to make it a global EQ that is independent of the cross-over of both the mains and the subs, because some corrections are often needed right in the middle of a cross-over area.

In your case, with only one sub. I would measure the speakers alone in the MLP, within a half a meter around that too... to kinda get an average, so that it is just a bit smooth, even though you move your head a bit or slouch during listening... you know... sometimes we are tired :D
In doing so, I would apply a low order high-pass filter to them, if your mains are not already falling with a second order slope downwards. This gives you a good starting point to mate the subwoofers with them, since you now know what to aim for.
Then you add the subwoofer, trying to fiddle both with placement and phase, cross-over ( the sub may easily cross higher than your mains do ), so that you end up with a response that have as few or very narrow suck-outs. And then you EQ ( on the input of the amp ) down the excess FR until the total response is smooth and even.

Sub frequencies are long and bounce quite a bit around the room before we "identify" them as bass. So that is one of the reasons you can't cross between mains and subwoofers like it was a cross-over between a midrange and tweeter.

Another approach, since you only have one sub, is to move the sub closer to the mains and treat it like an extension, kinda like having 3 way speakers. Then you can more easily use a bit more traditional approach with cross-over and EQ, since the system is now acting more like an all-in-one speaker - so to speak.

If you really want to make it better, and you find all approaches fruitless, then maybe the following story is the way to go - even though it might require extra fiddle.
I helped one of my friends who have a set of Focal Alto Utopia BE, where the bass was just wrong in his also very square room. A 4 channel DSP and rather cheap SVS and Klipsch subwoofer, one on the far rear left corner and one on the far right middle, cleared it all up with WAY smoother and controlled response all over the room. So maybe you need 2 cheaper subwoofers, rather than one "expensive". Maybe the built-in DSP is fine, or else a mini-dsp is quite cheap, especially for sub-use.
One of the reasons I love multiple subwoofers, is because even if I just EQ'd the mains, two people can't even enjoy the same level of quality bass, just sitting next to each other.

Please turn all nobs and push all buttons, and do not avoid overlapping the response between subs and mains. Your equipment won't break, and it's a huge learning experience that I would not personally have been without, since I also still learn, even though the people I've already helped are satisfied :)
 

Digital_Thor

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I don't really understand most of the suggestions here. What is their goal?
Sometimes it seems that, if you help people philosophy about their own decisions, they will come up with their own most satisfactory solution.
For me personally, I often drain out all possibilities fully, to end up accepting the best one left - like canceling out, until my mind is at peace, even though it can be less logical for some, that already made up their mind long time ago.
 

radix

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Can i really point a sub at a wall without a lot of distance (say 5cm)? Is there enough space so freuqncies spread and doesnt cancel itself back from wall reflection? Seems like the intuitive thought

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.
 

Koeitje

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Thanks, Yeah in really heavy Bass content (deadmau5, Skeler)
Are you sure that bass goes low enough? Can just be punchy bass in the 45-70hz range.
 
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