• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

Bass Peaks and Dips

Joined
Dec 19, 2020
Messages
71
Likes
19
Location
Pacific Northwest, U.S.A.
8F6969EB-0EAC-4D4A-9A64-D9BF16AF1872.jpeg

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
 
Last edited:

staticV3

Master Contributor
Joined
Aug 29, 2019
Messages
8,013
Likes
12,852
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

Master Contributor
Forum Donor
Joined
Feb 27, 2019
Messages
5,835
Likes
9,577
Location
Europe
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.
 
Last edited:

DVDdoug

Major Contributor
Joined
May 27, 2021
Messages
3,033
Likes
3,995
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.
 
OP
MajorMajorMajorMajor
Joined
Dec 19, 2020
Messages
71
Likes
19
Location
Pacific Northwest, U.S.A.
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

Addicted to Fun and Learning
Forum Donor
Joined
Oct 10, 2020
Messages
806
Likes
2,638
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

Master Contributor
Technical Expert
Forum Donor
Joined
Mar 15, 2016
Messages
7,906
Likes
16,731
Location
Monument, CO
OP
MajorMajorMajorMajor
Joined
Dec 19, 2020
Messages
71
Likes
19
Location
Pacific Northwest, U.S.A.
OP
MajorMajorMajorMajor
Joined
Dec 19, 2020
Messages
71
Likes
19
Location
Pacific Northwest, U.S.A.
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.
 

DonH56

Master Contributor
Technical Expert
Forum Donor
Joined
Mar 15, 2016
Messages
7,906
Likes
16,731
Location
Monument, CO
Sure bass trap, but how many? In a small room, with lots of traps, how will it look? Like a recording studio?:oops:
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.
 
Top Bottom