What happened to my room acoustics

I measured the spectrogram for my room at my MLP, and the FFT results are as follows:

- There is a roll-off before 20kHz.

- A dip is present around 12kHz.

- There is a noticeable boost between 50Hz and 1.5kHz.

- The bass rolls off around 33Hz at -3dB, consistent with the factory rating.

Comparing these measurements to the Burchardt measurements, there are some differences:

- It doesn’t exhibit a roll-off before 20kHz.

- The dip is around 15kHz.

- The boost between 50Hz and 1.5kHz is not as pronounced as in my room.

I’m curious about what might be happening with my room acoustics. If a fix is possible, what would it entail?

Spectrogram from my zoom


My room / speakers setup


Measurements from Burchardt


Sorry for having strong feelings on this...but it was what saved my system/and my speakers from the chopping block.I read an article in galen carol website..."everything matters".This was after searching for some answers on setup.Turned out just some loose spikes under sound anchor stands...Tightened them down/re setup speakers....Totally transforming.Sound stage snapped in,had tight bass,ect.I had to redo setup a skosh... but the work was worth the effort.Sorry for add butt...


@digsmithd @mijostyn I found myself repeating an experiment I had conducted before concerning the decoupler/coupler between bookshelves and stands. This might turn into he says she says situation. Among springs, Moon gel, and rubber (by 3M), once again, Moon gel outperforms rubber and springs in terms of bass note weight and articulation. Springs are the least effective yielding soft bass. Rubber does have some degree of coupling effect. I agree with what you and others have mentioned about spikes being couplers. While spikes may tighten up the bass, they can also make it sound lean. I recall Paul McGowan attesting to this before.

Sorry, I just need to trust my ears in this case.


What you are listening to is distortion, bass resonance. Little loudspeakers do this all the time intentionally to give the impression of bass. I can understand wanting more bass power and weight. The best ways to do this are Digital Signal Processing and subwoofers. 


@mijostyn  I cannot speak for Mr. McGowan, but I respectfully disagree with you regarding the distortion you have proclaimed. I believe, as a bass guitar player in a college band, I can discern between distortion and natural bass. Overly tight bass can become unnatural. Two-channel system listening experiences are subjective, and it's essential to learn to agree to disagree.

I am on board with DSP and I hope it works to resolve the issues I was having.

Subwoofer is another contentious topic for tomorrow.  

i own little speakers with a 4 inches woofer which i modified and i had clean bass at 50 hertz no boominess ...😊

How ? saying that we are in the obligation to use dsp and subwoofers as only one solution for little speakers is ignorance ...

I used four solutions :

--One mechanical which is damping with a heavy load on top of speakers when possible ...

--Isolating/decoupling with granite blocs /shungite plate/sorbothane plate /cork plate/bamboo plate sandwich which is very efficient ... ( springs can be effective by the way but ONLY used in a certain way with PRECISE tuning control of the compressive load on the springs but i dont need springs with these light smaller speakers with my other bigger speakers i used two set of springs under and over the speakers under tuned load with a precision around 100 grams this method of using springs though is not practical for all especially in a living room )

--Using my porthole speakers for what they are  acoustically : Helmholtz resonators...Then i put bundle of  straws of dfferent diameter and lenght in the rear porthole, all  mechanically tuned then to increase bass depth and clarity going from the 85 hertz specs to 50 with great clarity and impact ...I dont need costly pair of subwoofers to listen jazz and classical ...

--Using adequate room treatment and if necessary  room  distributed Helmholtz resonators ( i had many in me first acoustic room with bigger speakers but  in this acoustic smaller room i use the speaker itself as a resonator which i control ...)

Cost: peanuts ... Results : amazing ...

and a complete transformation of these well reviewed  low cost speakers which now punch way over their price and beat all the headphones i listened to ...


Then proposing general recipe for all case and for all people situations as some mandatory subwoofers when anyway they are not needed and present hard problems of their own, and some DSP equalization for bass problems presented as ONLY solution is ridiculously narrow perspective ... Tools are tools not exclusive solutions ...

To solve a room problem anyway we MUST BE THERE LISTENING and adressing the room mechanically and not only electronically especially with bass problems .. ...

Small room acoustic is very complex...General recipe means little each case of specific speakers and specific room is a problem of its own asking for a specific tuning of the couple room speakers ...