ok im opening pandoras box here.(treatment vs framed wall art)

davehrab
337 posts
07-24-2016 12:11pm
"The pictures on your wall are vibrating in response and sympathy to your room's 3 primary resonate frequencies being excited or over pressurized

Every room has 3 primary resonate frequencies based on the room's physical dimensions between the parallel walls for it's height .. width and length....etc., etc.,"

the vibration theory of the pictures can be easily dispensed with by performing the experiment of removing the pictures from the room fir a headphone based system, you know, one that won't excite the pictures to vibrate. The other way to test the effects of pictures in the room is tape photos of the pictures to the wall. That way you can eliminate the pictures vibrating theory.

cheers

A big shout-out for Marigo VTS dots for windows and walls and for those teeny tiny little bowl acoustic resonators.

Speaking of opening Pandora’s box, while almost everyone and his brother would probably agree glass resonates and that glass windows and glass framed pictures and just ordinary drinking glasses in the room might not be a good idea sound quality wise, what isn’t well known is that the pictures themselves hurt the sound. Especially if the pictures are of people, birds of prey, predators such as lions or tigers or sharks, military aircraft, things of that nature; in other words, things that could easily represent a threat to the listener, consciously or subconsciously. Thus, if you remove all pictures, even ones you might deem innocuous, from the listening room and invite your friend over to listen to the system he will hear a marked improvement to the sound. This will be the case even if the pictures are NOT covered by glass. For best results pictures should be taken entirely outside the house since they can still affect the sound even if they’re in other rooms.

While we’re on the subject of unconventional room treatments can I offer up the following for your consideration? Crystals for addressing sound pressure peaks in the room, DIY Helmholtz resonators using the Helmholtz formula to calculate the nozzle diameter and length and resonator volume for the frequency of interest, Shun Mook Mpingo disc, removing (resonating) objects in the room that interfere with the sound such as beer bottles, CD jewel cases, musical instruments, chest of drawers, that sort of thing. Here's a flashback: one or more medium-large size box filled with crumpled up newspapers in each corner of the room. A cheap man's tube trap?

g. k.
machina dynamica
we do artificial atoms right!

"But my original post was regarding some of the mega systems here on the gon virtual.I see some serious setups and wonder how the hell does he have 20 framed glass pics on his walls??? How is he/she battling the resonation that has to be taking place."

good question. One would see the same situation in ALL rooms at CES and other audio shows. No one seems to address the potential resonance issue related to ranked glass pictures on the wall. Which actually begs the question, is having resonators on the wall a bad thing? I can image these unintentional resonators might actually be beneficial to the sound by dissipating unwanted energy that occurs when the walls vibrate. And a lot less expensive than those precious metal tiny bowl acoustic resonators. 

oleschool OP
172 posts
07-27-2016 12:11am
Geoff i hear ya . But what is the frequency they are vibrating at ? Above our hearing ? When my pics vibrate its the frame ratting on the wall itself so say under 100hz ? But the glass itself i would think is just ringing at a high frequency (causing brightness i would think ) I am just guessing . I still would like someone with the means to try some sr or simalar on the glass itself . There was a system here that had maybe 40 pics on the walls ??? Thats so much glass , mostly just curious.

Every object has it’s own resonant frequency. An object will resonant or ring (only) when excited by a mechanical or acoustic vibration of its resonant frequency. So, depending on the size and thickness of the glass, the the glass will ring when acoustic waves of the resonant frequency excite it - or vibrate along with the frame/picture. I also suspect the grip of the frame on the glass might damp the ringing. People sometimes assume tiny metal bowl acoustic resonators or ebony discs produce high frequency distortion (excess brightness) when they resonate but they actually don’t. That’s why I said it’s possible the glass in the frames is acting as an acoustic resonator but the pictures probably wouldn’t be located in the right places on the wall to provide the benefit since placement is key.

oleschool OP
174 posts
07-28-2016 1:23am
Geoff,
What your saying I believe is spot on ,but again wouldnt this type of set up (glass pics behind spkrs side walls etc ) greatly effect the sound in the room?

It seems to me it would be easy enough to find out by listening with and without the pics. Not sure the results are necessarily predictable, however.