Bass Peaks and Dips

[MajorMajorMajorMajor]

Hi All,

If you look at the attached, you’ll see a frequency sweep I ran up to about 3k on my system, listening form the listening position.

You’ll see that there is a dip around 75hz (anticipated, I can correct,I think), and a peak at around 200hz.

Does anyone else have this problem of a certain frequency being much higher than others, consistently?

It’s also there when playing music, of course.

It’s a small room without bass traps. Can I buy a bass trap specifically to treat this?

Would it make sense to EQ this out or is this the result of the bass bouncing around? (I have the Audyssey App for my DENON Receiver, it does allow for EQing the speakers and sub.)

thanks

 

[staticV3]

Does anyone else have this problem of a certain frequency being much higher than others, consistently?

They're called room modes.
Everyone with speakers in 'a room' will encounter room modes.

It’s a small room without bass traps. Can I buy a bass trap specifically to treat this?

Yes.

Would it make sense to EQ this out or is this the result of the bass bouncing around?

Destructive interference, so nulls or dips can hardly be EQed out. You can reduce peaks with EQ though.

 

[LTig]

If you look at the attached, you’ll see a frequency sweep I ran up to about 3k on my system, listening form the listening position.

You’ll see that there is a dip around 75hz (anticipated, I can correct,I think), and a peak at around 200hz.

You can correct (dampen) peaks with EQ. Dips cannot be corrected by EQ since these are cancellations.

Does anyone else have this problem of a certain frequency being much higher than others, consistently?

Everybody with speakers in a room sees those.

It’s a small room without bass traps. Can I buy a bass trap specifically to treat this?

Yes.

Would it make sense to EQ this out or is this the result of the bass bouncing around? (I have the Audyssey App for my DENON Receiver, it does allow for EQing the speakers and sub.)

It's worth a try.

 

[DVDdoug]

Can I buy a bass trap specifically to treat this?

Possibly not "a" bass trap... It might take more than one... I'm not an acoustics expert and I don't know anything about your room. Even an expert might have to use some trial-and-error.

Since bass traps absorb the reflected bass, they can help with both the peaks and dips.

 

[MajorMajorMajorMajor]

They're called room modes.
Everyone with speakers in 'a room' will encounter room modes.


Yes.


Destructive interference, so nulls or dips can hardly be EQed out. You can reduce peaks with EQ though.

Great, thank you

 

[dominikz]

View attachment 337485
Hi All,

If you look at the attached, you’ll see a frequency sweep I ran up to about 3k on my system, listening form the listening position.

You’ll see that there is a dip around 75hz (anticipated, I can correct,I think), and a peak at around 200hz.

Does anyone else have this problem of a certain frequency being much higher than others, consistently?

It’s also there when playing music, of course.

It’s a small room without bass traps. Can I buy a bass trap specifically to treat this?

Would it make sense to EQ this out or is this the result of the bass bouncing around? (I have the Audyssey App for my DENON Receiver, it does allow for EQing the speakers and sub.)

thanks

Response dips are often caused by speaker-boundary interference (SBIR), which is influenced by how far loudspeakers are from adjecant walls. E.g. a 75Hz dip would happen if the front of the speaker is placed 1,15m from the wall behind it.
I wrote a bit more about the effect recently here, in case it helps.

 

[DonH56]

A quick overview can be seen in a couple of articles I wrote some time ago:
Room Modes: https://www.audiosciencereview.com/forum/index.php?threads/room-modes.25433/
Comb Filter Effects: https://www.audiosciencereview.com/forum/index.php?threads/comb-filter-effects.25432/

Lots of good information and a decent room mode calculator can be found on the Harman site: https://www.harman.com/audio-innovations

HTH - Don

 

[MajorMajorMajorMajor]

A quick overview can be seen in a couple of articles I wrote some time ago:
Room Modes: https://www.audiosciencereview.com/forum/index.php?threads/room-modes.25433/
Comb Filter Effects: https://www.audiosciencereview.com/forum/index.php?threads/comb-filter-effects.25432/

Lots of good information and a decent room mode calculator can be found on the Harman site: https://www.harman.com/audio-innovations

HTH - Don

Those Harman resources are awesome! Thank you!!

 

[MajorMajorMajorMajor]

A quick overview can be seen in a couple of articles I wrote some time ago:
Room Modes: https://www.audiosciencereview.com/forum/index.php?threads/room-modes.25433/
Comb Filter Effects: https://www.audiosciencereview.com/forum/index.php?threads/comb-filter-effects.25432/

Lots of good information and a decent room mode calculator can be found on the Harman site: https://www.harman.com/audio-innovations

HTH - Don

I looked into the posts you wrote as well. Very helpful, thank you.

 

[DanielT]

Sure bass trap, but how many? In a small room, with lots of traps, how will it look? Like a recording studio?
Cost?

Isn't it better to just EQ and take it from there?

 

[DonH56]

Sure bass trap, but how many? In a small room, with lots of traps, how will it look? Like a recording studio?
Cost?

Isn't it better to just EQ and take it from there?

EQ will usually bring down a peak but is ineffective for true nulls. For the latter, treatment doesn't usually help unless you have a lot of it, so the usual solutions are to move the listening position and/or add subs to compensate the room modes.

 

[KEM]

View attachment 337485
Hi All,

If you look at the attached, you’ll see a frequency sweep I ran up to about 3k on my system, listening form the listening position.

You’ll see that there is a dip around 75hz (anticipated, I can correct,I think), and a peak at around 200hz.

Does anyone else have this problem of a certain frequency being much higher than others, consistently?

It’s also there when playing music, of course.

It’s a small room without bass traps. Can I buy a bass trap specifically to treat this?

Would it make sense to EQ this out or is this the result of the bass bouncing around? (I have the Audyssey App for my DENON Receiver, it does allow for EQing the speakers and sub.)

thanks

Corner traps will help with the sub 200Hz peaks and dips. Wall traps will help reduce the 200 Hz peak somewhat. There's great info about the different kinds of traps and effectiveness on Ethan Winer's Real Traps website.