Bass issues in my room

[Mordante]

Last week I did some measurement using REW in my living room. It confirmed my suspicions that I have a bass problem. I already have 2 GIK soft fit bass trap with scatter plates and 4 Daad4 absorbers. I was thinking of buying 4 to 6 more GIK soft fit bass traps. I am in doubt if I should buy these with the scatter plate or with the range limiter.

But before I order anything I would like your opinion. Another option is buying 2 Psi Audio AVAA C214 but that is way more expensive.

The reason I like GIK is because they produce in German so transport costs would be relatively low. My room is about 4*7meters.

 

[Mike]

was the measurement done from your listening chair? If so, move the microphone around the room to find the flattest (below 200hz) listening spot.

PSI AVAA’s work magic. Depending on the size of your room, 2-4 generally do the trick.

 

[Bones13]

Low bass is hard to correct with wall absorbers. Moving the speakers or seating area can help more. My previous room had a 40hz boom. The correct type and number of the GIK 40hz absorbers involved 8-10 of the 2x2 foot tuned absorbers (which were quite thick). I did not use a sub, nor did cover the walls of my 9.5 x 14 room with the tuned bass traps)

The active AVAAs are good. You could also use some form of equalization to lower the bass. REW can make a convolution file to load in Roon, but I have not done that. (I play vinyl, and Roon does not correct that stream) There are many other ways to do equalization. (Room Correction)

 

[Mordante]

was the measurement done from your listening chair? If so, move the microphone around the room to find the flattest (below 200hz) listening spot.

PSI AVAA’s work magic. Depending on the size of your room, 2-4 generally do the trick.

The PSI is 3400euro each the digital version. You can buy a lot of room treatment for that kind of money. Six bass traps is cheaper than 1 PSI,

 

[Mordante]

Low bass is hard to correct with wall absorbers. Moving the speakers or seating area can help more. My previous room had a 40hz boom. The correct type and number of the GIK 40hz absorbers involved 8-10 of the 2x2 foot tuned absorbers (which were quite thick). I did not use a sub, nor did cover the walls of my 9.5 x 14 room with the tuned bass traps)

The active AVAAs are good. You could also use some form of equalization to lower the bass. REW can make a convolution file to load in Roon, but I have not done that. (I play vinyl, and Roon does not correct that stream) There are many other ways to do equalization. (Room Correction)

Indeed I have to move my listening position and test again. I don't have much room to move the speakers atm.

 

[crwilli]

The PSI is 3400euro each the digital version. You can buy a lot of room treatment for that kind of money. Six bass traps is cheaper than 1 PSI,

Yes they are expensive but they are many times more effective than simple bass traps. To impact your low bass area you will need traps meters deep. That is usually not feasible in most rooms.

As Mike suggested earlier, moving your listening position forward or back can pay dividends. If you have more flexibility on your LP, do as Mike suggests and measure different locations around your LP. You might find a location with much smoother bass within a reasonable distance from where you are now.

 

[Mike]

Yes they are expensive but they are many times more effective than simple bass traps. To impact your low bass area you will need traps meters deep. That is usually not feasible in most rooms.

As Mike suggested earlier, moving your listening position forward or back can pay dividends. If you have more flexibility on your LP, do as Mike suggests and measure different locations around your LP. You might find a location with much smoother bass within a reasonable distance from where you are now.

Get the room and setup right and everything sounds 10 times better. That’s invaluable.

We are a funny bunch.

 

[mep]

Get the room and setup right and everything sounds 10 times better. That’s invaluable.

We are a funny bunch.

That's true!

 

[Mordante]

Get the room and setup right and everything sounds 10 times better. That’s invaluable.

We are a funny bunch.

A while ago two friends (one is on this forum I think) came over to set-up speakers in the best location. That really helped with the stereo image.

I will do some measurements again testing different listening/speaker locations. Just yesterday I singed to have the window in my living room replaced. for that I will need to remove my whole set while they replace my windows. This will be at the end of April. I think after that I will start play around with speaker placement and listening/measuring.

I am also wondering if changing the glass will have an impact. It is triple glass. The glass + isolation layers will have a total thickness of I think 4cm.

So you have an idea of what it currently looks like.

 

[Mike]

A while ago two friends (one is on this forum I think) came over to set-up speakers in the best location. That really helped with the stereo image.

I will do some measurements again testing different listening/speaker locations. Just yesterday I singed to have the window in my living room replaced. for that I will need to remove my whole set while they replace my windows. This will be at the end of April. I think after that I will start play around with speaker placement and listening/measuring.

I am also wondering if changing the glass will have an impact. It is triple glass. The glass + isolation layers will have a total thickness of I think 4cm.

So you have an idea of what it currently looks like.

View attachment 34213

Play pink noise, use a spectrum analyzer, note 200hz and below. You are looking for the flattest, not highest or lowest, flattest response. Move SLOWLY around the room. Once you see the flattest (it will never be perfectly flat), stop. Mark it. Put your chair there. Then use the 83% rule from there starting with 8-12 feet max from ear to tweeter, then that distance (say 10 feet) x .83 for tweeter to tweeter keeping same distance to side wall.

We do this for our customers.

 

[NewAlkyogre]

 

[Mordante]

Play pink noise, use a spectrum analyzer, note 200hz and below. You are looking for the flattest, not highest or lowest, flattest response. Move SLOWLY around the room. Once you see the flattest (it will never be perfectly flat), stop. Mark it. Put your chair there. Then use the 83% rule from there starting with 8-12 feet max from ear to tweeter, then that distance (say 10 feet) x .83 for tweeter to tweeter keeping same distance to side wall.

We do this for our customers.

Do know free software for this or an phone app I can use for the spectrum analysis.

 

[Mike]

Do know free software for this or a phone app I can use for the spectrum analysis.

No, you’ll have to spend a nickel. I use Spectrum Analyzer RTA for iPhone.

 

[Barry]

Nice thread. Great info and simple to follow.

 

[atmasphere]

Last week I did some measurement using REW in my living room. It confirmed my suspicions that I have a bass problem. I already have 2 GIK soft fit bass trap with scatter plates and 4 Daad4 absorbers. I was thinking of buying 4 to 6 more GIK soft fit bass traps. I am in doubt if I should buy these with the scatter plate or with the range limiter.

But before I order anything I would like your opinion. Another option is buying 2 Psi Audio AVAA C214 but that is way more expensive.

The reason I like GIK is because they produce in German so transport costs would be relatively low. My room is about 4*7meters.

View attachment 34211

Looks like a pretty pronounced cancellation in the bass. In many rooms that is caused by a standing wave. If that is the case room correction and bass traps won't fix it. That is because room correction means amplifier power and that's getting canceled.

To correct this issue you need subwoofer. It might be only a couple (depends on the frequency your main speakers roll off). In my setup my speakers are flat to 20Hz so I only needed a pair of subs to break up the standing wave. I didn't have a lot of room so I used a pair of Swarm subs from Audiokinesis; one of the very few that is designed to be directly against a wall; IOW they are taking advantage of the room boundary effect to extend their low frequency bandwidth while keeping their size down. So they are flat to 20Hz as well.

The nice thing is this approach was also inexpensive and very effective. If you have a standing wave issue (and most do if the room is regular proportions) then room correction won't be effective until after the standing waves are broken up. Put another way using subs to fix this problem is about 95% effective while bass traps and room correction are good for about 5%.

Pro tip: If using only one sub, do not point it at you; instead point it at an angle so the bass wave bounces off a wall before getting to you. In this way you'll get far better bass coverage in the room (less likelihood of standing waves).

Why this works: at 80Hz the waveform is 14 feet long; at 40Hz 28 feet. Your ear needs the entire waveform to pass by you before it can know the note is there; a few more iterations and it can tell what note it is. With waveforms that long by the time you know what note is playing its bounced all over the room and may be canceling itself. This also implies the sub does not have to be time aligned with the main speakers. However, if the sub or subs has output above about 80Hz this may not be so- they might draw the ear's attention.