simple 2 channel setup - how to treat boomy bass

[audfrknaveen]

hey guys,

please see the attached image.

I kept my bookshelfs in left and right corners of the front wall.
I know corner placement is very bad. But I can't move them away from walls by more than 1/2 ft.

What other things can be done to reduce boomy bass?
Any suggestions are greatly appreciated.

Thanks & Regards,
Audfrknaveen

 

[Bigun]

If your speakers are bass reflex, i.e. they have ports in them, try stuffing the port holes with some pillow fibres or similar to reduce bass output or stuff them with something more solid such as some foam, or plugs made from rubber. You'll find somewhere along the way you'll hit on the right amount of stuffing.

 

[audfrknaveen]

Well ...I already closed the ports. So there is slight improvement.

In terms of treatment, I'm checking what all can be done.

 

[audfrknaveen]

Irony is, we don't want to reduce bass. We need it more, but we need it clean ...ha ha

 

[rayma]

If you can't move them towards each other, move each of them forward.

 

[audfrknaveen]

In both directions only 1/2 ft I can move. Not more than that. It's unfortunate, but I don't have an option there.

So assuming placement as a compromise, what other things we can try, I'm wondering.

Or let us assume they are sealed on wall speakers, obviously we keep it on the wall. So in such cases what to do to get best transient bass

 

[Pano]

You might try putting them right into the corners with a baffle that goes wall to wall across the corner. I've had good success with that using large speakers.

 

[krivium]

If put into a corner your loudspeakers will see boundary reinforcement in the bass area: +3db for each close walls.

So if you have a bit of ceiling height assuming a net gain of +9db should be more or less within the ballpark.

So if you have access to a low sheving eq you already have one of the parameter (almost) defined (~ -9db). The one remaining is the frequency at which this should be located.

If you have a microphone and an rta you can approximate it. If not then headphone and comparison experiment could land you in the ballpark.

For better transient response i agree with bigun: make them sealed.

Then as you already have an eq engaged why not go a step further and include a Linkwitz Transform to make the QTC of your loudspeakers close to 0,577 (or 'complement' your room)?

There you'll need a mic and a software like REW.

 

[audfrknaveen]

You might try putting them right into the corners with a baffle that goes wall to wall across the corner. I've had good success with that using large speakers.[/QUOTE
You kept The rear side of the baffle empty? Or you filled with any bass traps

 

[audfrknaveen]

You might try putting them right into the corners with a baffle that goes wall to wall across the corner. I've had good success with that using large speakers.

If put into a corner your loudspeakers will see boundary reinforcement in the bass area: +3db for each close walls.

So if you have a bit of ceiling height assuming a net gain of +9db should be more or less within the ballpark.

So if you have access to a low sheving eq you already have one of the parameter (almost) defined (~ -9db). The one remaining is the frequency at which this should be located.

If you have a microphone and an rta you can approximate it. If not then headphone and comparison experiment could land you in the ballpark.

For better transient response i agree with bigun: make them sealed.

Then as you already have an eq engaged why not go a step further and include a Linkwitz Transform to make the QTC of your loudspeakers close to 0,577 (or 'complement' your room)?

There you'll need a mic and a software like REW.

My speakers are JBL A130. The speakers are giving better transient bass in a larger hall and placed away from walls.

In this particular room I'm guessing the room is making some frequencies reverb for longer durations.

So I'm looking in the direction which room treatment may solve the issue. I can't make chenges within the speakers.

 

[academia50]

Irony is, we don't want to reduce bass. We need it more, but we need it clean ...ha ha

And why don't you treat the room? Aside from the measurements, we don't know much about the content within it.
I wouldn't be surprised if there aren't any rugs, cushions, curtains, or anything else that helps absorb resonances within the room.
If you can have the three mentioned, all the better.
What speakers are they?
Does the amp have a tone control? Of Loudness?

 

[audfrknaveen]

JBL A130 and Yamaha stereo amp.
Well I'm ready to treat the room.

I'm wondering where to start, what to treat, which locations in room etc etc.

I don't have any issue with mids and highs.
Only target is to increase accuracy of bass.

 

[academia50]

What model of Yamaha?
What has been mentioned to you before about the bass gain by placing the speakers in the corners is valid, so, does not it improve something when using bass and loudness controls on the Yamaha?
Likewise, the most efficient solution will be acoustic treatment.

 

[krivium]

My speakers are JBL A130. The speakers are giving better transient bass in a larger hall and placed away from walls.

In this particular room I'm guessing the room is making some frequencies reverb for longer durations.

So I'm looking in the direction which room treatment may solve the issue. I can't make chenges within the speakers.

Pano's answer ( and Bigun's as well as mine) are answer to your issue ime.

I don't know of acoustical treatments which will makes disappear 9db of gain in the low end without fullfill entirely your room with rockwool.

We don't suggest to makes change to your loudspeakers ( except plug the ports to make them sealed with... some sockets or other fabric), rather put them in a location where their behavior can be predicted approximately and then use an eq on your source to counteract the acoustic behavior ( which is minimum phase so can be corrected by eq).

My suggestion about a Linkwitz Transform is the same: some eq to adapt the behavior of your loudspeakers to your room ( as you insist on transient you won't find anything better than closed with 0,577/0,6 qtc).

What is/are your source(s)?

 

[academia50]

There is a problem there, that speaker has the tuning tube in the back ..... It will not be the total solution, but you should move it as far as possible from the wall.
Have you thought of some nice feet to place away from the walls?

JBL Stage A130 Review (speaker) | Audio Science Review (ASR) Forum

 

[academia50]

https://www.amazon.com/Atlantic-77335799-Speaker-Bookshelf-Speakers/dp/B007P8DKDE

 

[Bigun]

There is a problem there, that speaker has the tuning tube in the back .....

He said he has plugged the ports, so it matters not which face of the box they are in ?

 

[academia50]

Pano's answer ( and Bigun's as well as mine) are answer to your issue ime.

I don't know of acoustical treatments which will makes disappear 9db of gain in the low end without fullfill entirely your room with rockwool.

We don't suggest to makes change to your loudspeakers ( except plug the ports to make them sealed with... some sockets or other fabric), rather put them in a location where their behavior can be predicted approximately and then use an eq on your source to counteract the acoustic behavior ( which is minimum phase so can be corrected by eq).

My suggestion about a Linkwitz Transform is the same: some eq to adapt the behavior of your loudspeakers to your room ( as you insist on transient you won't find anything better than closed with 0,577/0,6 qtc).

What is/are your source(s)?

Don't look to others for support as if you were a gang member here ...

All your explanations are very theoretical, they involve extra money and a lot of time to experiment.
It's not the OP's situation.
It won't do you much good to know that you earn 9 DB for corner placement.
This is a forum to help, to collaborate within the possibilities and knowledge of those who come to us.
You are mistaking the course due to your uncontrollable desire to show your knowledge, which on the other hand, is nothing new or something that most of us here do not know, but unlike you, I and a few others try to provide solutions within the reach of the OP, don't give him an advanced acoustics class.
Have you thought about entering AES?

 

[academia50]

He said he has plugged the ports, so it matters not which face of the box they are in ?

Keep your socks that winter is coming, they will be more useful than plugging the tuning tube.

 

[krivium]

Academia,
I was member of AES as an audio engineer and was a teacher in a school of audio engineering in a previous life yes.

I thought sharing knowledge and experience was the point of being a member here, but maybe i didn't understood the point and we had to reinvent the wheel or being creative in presenting 'new idea'.

Please point me to your revolutionary approach to anything you presented here, i'm eager to learn new things.

One thing i learned when i was teaching was that explaining the theory behind something is usually easier to understand what have to be done in practice.

Please tell me too in what i suggested to spend money? The eq?

Well my friend it is time to leave the 19 century and take a look at what a plug in is ( and the plethorical offer of free ones availlable) and consider many people use computer as source this days.

And it is a joke as you pointed to an Amazon products which cost money. 😀

I don't consider to be part of a gang or either because i interacted with someone in the last 24hours the individual to be part of my family.

But hey, you didn't seems to understand what Pano and Bigun were implying in their answers, neither you had read the OP first post as he can't move his loudspeakers more than 1 foot away in each directions...

I bother you Academia? ...that's fine. You don't have to read what i write, neither to interact with me too. And i'm really sorry to share on things i know of ( as it was my job) and not on things i don't. 😀

With love. 😀

Ps: keep on with your own view of the issue, it is always fine to have multiple different view for someone asking about a problem. 😛