The problem is that people confuse at least three vocabulary :
Audiophile vocabulary.
Acoustic vocabulary.
Musical vocabulary.
The most important concept in hearing acoustic about playback system experience in a room, or about live performance listening in a great Hall is listener envelopment and his relation with the auditory source width LV/ASW. ( crosstalk with playback system and timbre are the other two)
Now if we try to understand what it is and how to control the related physical parameters reading audio threads or audiophiles magazine we will go nowhere...😊
During the solar storm this week end i just put my final important last device to create this LV/ASW ratio in my system/room. ( i already created it in my first room/system few years ago)
The first time it was a grid of many resonators located in a bigger room.Now it was a single but more complex resonator with two other smaller resonators inside and many little open one around it..
*I put this complex closed Helmholtz resonators behind my listening position , I created it with an abandoned long big plastic pipe i pick walking. 😊With cardboard and many types of straws, i inserted in the tube two others smaller resonator tubes of different lenght. I also inserted around it open tubes resonators without absorbing floor. I tuned them by ears.
The result was so stunning that no other modification could compare, even the two big modification on my speakers, nor the isolation/coupling damping load for the speakers, nor the shielding of EMI nor the introduction of a tube preamplification etc ,
Nothing compare in impact for the listener envelopment factor improvement and auditory source width ratio improvement as with this resonator set. And i winned also at the end with a better "timbre" experience. ( acoustic passive treatment with a balance between absorption reflection and diffusion is not enough.Resonators are active not passive treatment of a room pressure zone distribution )
Helmholtz resonators are not only absorbing some frequencies band they also are diffusor for some frequencies band ... And open resonators are powerful diffusor...
Cost : peanuts...
Reading about acoustic vocabulary and concept matter the most ...Experimenting is funnier than buying and more rewarding.
By the way i get this idea about putting a resonator inside a resonator by contemplating my room : two speakers especially with porthole are simple Helmholtz resonators which are in a room open with a door then the entire room is a resonator with speakers resonators INSIDE it. My two ears canals are also resonators ...
I decided to create a resonator inside another one. 😊