Bass traps? (to solve a suck out)


I have a terrible suck out at 61Hz. What should I do to address, I cannot move my subwoofer or room.
gchuva
Hi Holeneck, you said "bass traps cannot fix a suck out, but you should still treat your room to achieve other benefits."

That is a completly false statement. Bass traps do indeed flatten peaks and raise nulls IE: fix suck outs. They also narrow the width of the peaks and nulls among other benefits.

Bob
A bass trap is a passive device that can only dissipate acoustic energy from a room. As such it can never eliminate a null in room response since it cannot add energy into the room. However, if you have two bass peaks it's possible that room traps can eliminate the peaks to generate smooth bass response. But in that case you didn't really have a bass null, but two bass peaks.

If you measure room response in narrow enough bands you'll typically find any number of very deep and very narrow nulls. As a practical matter they cannot be eliminated. Fortunately, they usually aren't a noticeable problem. Broad band nulls are a major problem. Repositioning the speaker and/or listener is the best way to address that type of problem.
Onhwy61 said "A bass trap is a passive device that can only dissipate acoustic energy from a room. As such it can never eliminate a null in room response since it cannot add energy into the room."

The energy is allready in the room (if your speakers/equipment are capable). The problem is a null is created when the waves come back to you and meet where you are positioned and those freq are cancelled and therefore not heard. Just the opposite of a peak where you are positioned at the peak of the waves coming together to reinfore that freq. A bass trap decreases the wave strength (reflection) and therefore decreases the null and at the same time brings down the peaks.

Onhwy61 said "But in that case you didn't really have a bass null, but two bass peaks."

So, have can you have peaks only and no nulls?

Bob