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Subwoofer didn't help fixing null. What do? (not buying 2+ subs) (presonus sub8 vs kali lp6)

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Slyman

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Thanks for the overwhelming amount of help. It's getting late and the bed is calling anyhow tomorrow I'll:

1) Move the sub along the wall with the driver facing 1/3 and 2/3 width directions.
2) Move the sub to a corner and try to see what happens. Hopefully less null and more eq cutting.
3) Investigate that 500hz dip (and perhaps the 4k/10k hz mess depending on measurement).

... And post the proces. Maybe someone will get the same problems as i face with subs and nulls in the future.

However even though its low cut its quite easy to hear its direction including it being just beside the table (instead of under). Phase switch (to 180hz) didn't work. It moved the null up a bit.

Again thanks for all the help and lovely to see the community alive against which i presume to be a common enemy: Nulls :)
 

Avp1

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First - remove HPF from speaker. Run them full range. Subwoofer still needs LPF. I hope your sub has variable phase - you will need it when it is far from speakers. You may try to move sub to back wall and play with phase adjustment. With 8" you only can go down to 40Hz or close. Do not expect any useful output lower than that.
 

YSC

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From my exp. the 90hz is likely caused by roof reflection (1/4 wavelength ~3.8m), whereas the 55 and 70hz ones I guess is the back wall reflection,these won't change when moving left to right, but maybe you can try moving it up/down and fron and back it could change location, with a single sub though it will always be at least 1-2 nulls as it's impossible to move to a position where no boundary reflection is present IRL
 
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Ellebob

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There might be a simple answer for this, but it might not be practical. If you are having a null because of a room mode, then it is happening at certain locations in your room. Using two subs well placed can reduce problem, but you can also correct it with one sub and moving the seating location.
Room modes happen at certain locations in your room and if you happen to be sitting in that null no amount of moving your subs/speakers around is going to change that. Sometimes it can lessen it where the peaks and nulls are not as pronounced but it won't eliminate it entirely.
So if it all possible, move your seating. Sometimes less than a foot can make a difference.
 
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pdfield34

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whereas the 55 and 70hz ones I guess is the back wall reflection,these won't change when moving left to right, but maybe you can try moving it up/down and fron and back it could change location,
Yes! This! This was my situation with speakers alone and then with speakers and subs placed beside each speaker. I noticed these nulls seemed to be quite common in other folks' measurements. HP my mains at 100 hz and moved the subs out in front of the speakers and that took care of the nulls. This image helped me out.
(total novice, but at least I think that is what was happening).

speaker-boundary-interference-response.jpg
 

dfuller

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The only thing that can really fix nulls like that is adequate room treatment. For low frequency (sub-schroeder) stuff, you either need hugely thick velocity absorbers (think feet thick of the pink fluffy stuff) or pressure traps (membrane traps, generally).

That, on top of placing speakers and subs correctly, will get you where you need to be.
 

YSC

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Yes! This! This was my situation with speakers alone and then with speakers and subs placed beside each speaker. I noticed these nulls seemed to be quite common in other folks' measurements. HP my mains at 100 hz and moved the subs out in front of the speakers and that took care of the nulls. This image helped me out.
(total novice, but at least I think that is what was happening).

speaker-boundary-interference-response.jpg
good that you managed to fix some of the nulls, the usual blind spot of sub placement is these image only shows the front wall (the wall you are facing, near the back of the speaker), but not taken care of the other surfaces in the room. in my tiny room all the walls are too close for the bass to be affected but I get a constant null caused by the roof, moving it under the desk helped a bit and that's where I left that in
 
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Slyman

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The large dip is shared by the speakers so try to move the sub out of line with the speakers, so don't align them. Move it closer to you or further away, or into a corner.
while you are at it, try with the subwoofer facing the frontwall (in the middle).
also try moving it up
I'd move the filter to 100Hz or 120 Hz. You likely need to move the sub around the room to find the spot that works best for your MLP.

A 80 Hz half wavelength is about 7' or 2.1m. So try moving the sub left/right by up to that amount, or putting it on a different wall, even if you have to temporarily run the cable across the floor. once you find a good spot, you can use a wireless transceiver if needed. You might also try the 0* vs 180* setting, to see if that helps.
Okay so after experimentation i had very positive results. Specially with this advice. Check this out:

When in corner, driver facing the corner, with 180* phase:
Corner.jpg


When in the middle of the speakers, drivers facing the front wall (so subwoofer is reverse to me), with 180* phase on:
Wall.jpg


To sum it up: I'm very happy for your advice and these results. My null when in corner is completely gone, and only a bit present when facing front wall. That is simply fantastic what some knowledge can do.

However, when it is in corner i can hear (i have a good ear) slight directivity from bass. Unless you guys think the frequency response is way worse, i think I'm chosing to face it against the wall and accept a small null... The dip at 500 hz is my next target though. Very strange. Table reflections?

As a final question i might ask about full range vs up to 300hz eq. As i understand it it only makes sense to adjust for room in lower frequencies (longer wavelengths). How far up the frequency spectrum should i EQ this? According to Dr. Toole up to 300hz is best (i'm using pro q3 in Ableton so limited bands too).

You guys are the best!
 
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Dj7675

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According to Dr. Toole up to 300hz is best (i'm using pro q3 in Ableton so limited bands too).
I would expand on that, in that if full Spinorama speaker measurements are available, he does not seem at all against speaker correction above 300hz. Basically you are correcting the speaker where it can be fixed/improved.
 

radix

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However, when it is in corner i can hear (i have a good ear) slight directivity from bass. Unless you guys think the frequency response is way worse, i think I'm chosing to face it against the wall and accept a small null... The dip at 500 hz is my next target though. Very strange.

As a final question i might ask about full range vs up to 300hz eq. As i understand it it only makes sense to adjust for room in lower frequencies (longer wavelengths). How far up the frequency spectrum should i EQ this? According to Dr. Toole up to 300hz is best (i'm using pro q3 in Ableton so limited bands too).

You guys are the best!
I'n glad you found a position that works.

You can still correct room modes with position and room treatments above 300 Hz. For example, I had a bad dip in a center speaker from 1 kHz - 1.5 kHz. I lifted it up about 4" and fixed most of it, at least in the MLP. The higher frequencies, the shorter the wave length, so the interference patterns repeat in shorter spacing, so it becomes harder to find a sweet spot. But you can use absorbers or other things to dampen reflections, or use EQ to bring down peaks.
 

sigbergaudio

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The dip at 500hz is too narrow to worry about. But the area 400-800hz could possibly be lifted a couple of db with a low q eq.
 
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Slyman

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I would expand on that, in that if full Spinorama speaker measurements are available, he does not seem at all against speaker correction above 300hz. Basically you are correcting the speaker where it can be fixed/improved.
Understood. Amir (blessed be his name) only did the Eris 5 XT tho. But you are right!

I'n glad you found a position that works.

You can still correct room modes with position and room treatments above 300 Hz. For example, I had a bad dip in a center speaker from 1 kHz - 1.5 kHz. I lifted it up about 4" and fixed most of it, at least in the MLP. The higher frequencies, the shorter the wave length, so the interference patterns repeat in shorter spacing, so it becomes harder to find a sweet spot. But you can use absorbers or other things to dampen reflections, or use EQ to bring down peaks.
Indeed. Also i mean at 500hz+ the wavelengths are below 80cm/listening distance and if something happens near my table or i move around its just variability. Room treatment for this for sure.

What crossover frequency are you using now?
The dip at 500hz is too narrow to worry about. But the area 400-800hz could possibly be lifted a couple of db with a low q eq.
Still 80hz HPF and 80hz low cut both set on subwoofer. The eris e5 and the eris sub8 are made to integrate so i'm trusting the manual. Its very nice they have the exact same volume setting tho at same spl. I'll experiment with 400-800hz but macs are annoying since you gotta pay for a system wide EQ. I'll update this post if that happens.

Anyways EQ settings are this:
EQ.jpg


Predicted target:
Predicted.jpg


And while listening to tunes in Ableton tho things are noticeble:

1) My monitors seems clearer now and less boxy... Too bright perhaps?
2) Bass is very thight and controlled.

I'm a bit afraid i eq'ed the bass away too much (theres some drastic cuts including -17.2db) and theres too much brightness. But maybe this is just what a semi-flat properly eq'ed setup sounds like. :~)
 

levimax

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Understood. Amir (blessed be his name) only did the Eris 5 XT tho. But you are right!


Indeed. Also i mean at 500hz+ the wavelengths are below 80cm/listening distance and if something happens near my table or i move around its just variability. Room treatment for this for sure.



Still 80hz HPF and 80hz low cut both set on subwoofer. The eris e5 and the eris sub8 are made to integrate so i'm trusting the manual. Its very nice they have the exact same volume setting tho at same spl. I'll experiment with 400-800hz but macs are annoying since you gotta pay for a system wide EQ. I'll update this post if that happens.

Anyways EQ settings are this:
View attachment 258320

Predicted target:
View attachment 258321

And while listening to tunes in Ableton tho things are noticeble:

1) My monitors seems clearer now and less boxy... Too bright perhaps?
2) Bass is very thight and controlled.

I'm a bit afraid i eq'ed the bass away too much (theres some drastic cuts including -17.2db) and theres too much brightness. But maybe this is just what a semi-flat properly eq'ed setup sounds like. :~)
I would not trust "predicted target", you need to make actual measurements "after correction", seldom if ever are the predicted target and measured results the same and often time not even close. From the predicted target it does look like the bass is too low... most people like a downward slope from LF to HF.
 

radix

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Understood. Amir (blessed be his name) only did the Eris 5 XT tho. But you are right!


Indeed. Also i mean at 500hz+ the wavelengths are below 80cm/listening distance and if something happens near my table or i move around its just variability. Room treatment for this for sure.



Still 80hz HPF and 80hz low cut both set on subwoofer. The eris e5 and the eris sub8 are made to integrate so i'm trusting the manual. Its very nice they have the exact same volume setting tho at same spl. I'll experiment with 400-800hz but macs are annoying since you gotta pay for a system wide EQ. I'll update this post if that happens.

Anyways EQ settings are this:
View attachment 258320

Predicted target:
View attachment 258321

And while listening to tunes in Ableton tho things are noticeble:

1) My monitors seems clearer now and less boxy... Too bright perhaps?
2) Bass is very thight and controlled.

I'm a bit afraid i eq'ed the bass away too much (theres some drastic cuts including -17.2db) and theres too much brightness. But maybe this is just what a semi-flat properly eq'ed setup sounds like. :~)
Yes, as @levimax said, you want a slope, maybe 10db from low peaks to 12k or so. Most people prefer a bit of a bass hump below 200 hz. If it sounds too bright, use a high shelf, say 8kHz, and bring it down. One you have it more-or-less flatish, you can then EQ to your particular taste.

The solid line in this figure is the "average person" preference. https://www.audiosciencereview.com/...e-why-is-it-represented-as-a-thin-line.19886/
 

sigbergaudio

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The prediction looks a bit optimistic, but assuming it's something like that, you need more level in the bass. It's not supposed to be flat / at the same level as the rest. You likely need at least 5dB more level on your sub, and if your EQ supports tilting the rest of the frequency band too, you should try getting a more even curve in the midbass as well. Something along these lines:

1674152886629.png
 
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Slyman

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I would not trust "predicted target", you need to make actual measurements "after correction", seldom if ever are the predicted target and measured results the same and often time not even close. From the predicted target it does look like the bass is too low... most people like a downward slope from LF to HF.
Yes, as @levimax said, you want a slope, maybe 10db from low peaks to 12k or so. Most people prefer a bit of a bass hump below 200 hz. If it sounds too bright, use a high shelf, say 8kHz, and bring it down. One you have it more-or-less flatish, you can then EQ to your particular taste.

The solid line in this figure is the "average person" preference. https://www.audiosciencereview.com/...e-why-is-it-represented-as-a-thin-line.19886/
Is this the case for studio monitors for mixing purposes (and not general listening). I mean in music mix-mastering isn't ruler flat the goal and not the harman curve?
 

sigbergaudio

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Is this the case for studio monitors for mixing purposes (and not general listening). I mean in music mix-mastering isn't ruler flat the goal and not the harman curve?

You will find people who claim that, but not really. But 10dB is probably too much. I'd try around 5-7dB.
 

radix

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Is this the case for studio monitors for mixing purposes (and not general listening). I mean in music mix-mastering isn't ruler flat the goal and not the harman curve?

The harman curve is what you want your in-room response to be, at least the starting point, and then EQ to your personal taste. A bit of a bass hump, then gradual slope, then a bit of fall off in the high frequency.
 
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