Put it to test how good or bad your expensive speakers are , around 05:00min :
(video in german sorry but you can switch to english in the settings , a bit tricky but works!)
Of course how strong the reaction of your speakers are , depends largely on the music you are using for this test! Use the normal playback level or somewhat higher to get a realistic impression of the unwanted noise that disturbs your high fidelity ambitions!
Easy to be done , takes no additional stuff , just some curiousity what's going on in your sound field during listening?
Why hasn't it be done as a standard test way back in history?
My suspicion is - most people fear to know how bad their speakers really are!
No excuse no more - kill all those sound devils that deceives you and take all your money , burning it in hell to torture those sinners down there
regards - death to all bad cabs
ps .. using pink noise for testing makes more sense and can be analysed to get a FR graph ...
Of course how strong the reaction of your speakers are , depends largely on the music you are using for this test! Use the normal playback level or somewhat higher to get a realistic impression of the unwanted noise that disturbs your high fidelity ambitions!
Easy to be done , takes no additional stuff , just some curiousity what's going on in your sound field during listening?
Why hasn't it be done as a standard test way back in history?
My suspicion is - most people fear to know how bad their speakers really are!
No excuse no more - kill all those sound devils that deceives you and take all your money , burning it in hell to torture those sinners down there
regards - death to all bad cabs
ps .. using pink noise for testing makes more sense and can be analysed to get a FR graph ...
addendum : Add some removeable foam strip around the baffle/close to the edge , to seal temporarily the gap between the speakers ... and be careful not to dent the protruding dome tweeters! (in case you underestimate the situation of putting the speakers so tightly together)
Of course the woofers need some "headroom" too so the rubbery parts can do their work unrestricted!
good luck!
Of course the woofers need some "headroom" too so the rubbery parts can do their work unrestricted!
good luck!
I've been using this trick for like 30 years, and later when I was in the industry I advised our Chinese speaker builder partners to use a similar arrangement for a more practical way of burn-in and stress-testing... think like 300 speakers on shelves in a small room all running pink noise at full bore... before that advice you could hear and feel the rumble in the whole factory and it was impossible to enter the room without double ear insulation.
So many chinese/taiwanese people building wonderfull things for our luxury life - good to give something back so they can live a happier life!
with all those rumbles in such a situation earthquakes can be detected later , maybe too late to run!
deadly loudspeaker hobby , only for LF enthusiast danger freaks
with all those rumbles in such a situation earthquakes can be detected later , maybe too late to run!
deadly loudspeaker hobby , only for LF enthusiast danger freaks
Shocking evidence of how bad your beloved DIY cabs really are :
Listen to his knocking against the side walls! (starting around 11:30min)
Speakers are original Acoustic Energy AE500 , 1200 euro for the pair ...
Do it as close as possible on your cabs (unmount the woofer and most of the damping stuff) , let a friend helping you and listen from a few feet away , like in the video!
Reality bites!
Listen to his knocking against the side walls! (starting around 11:30min)
Speakers are original Acoustic Energy AE500 , 1200 euro for the pair ...
Do it as close as possible on your cabs (unmount the woofer and most of the damping stuff) , let a friend helping you and listen from a few feet away , like in the video!
Reality bites!
Graph says what? Acoustical measurement close to side wall? Box size (approx.)? Old measurements from 2020 ! (date of graph upper right corner)
Please elaborate further ... how much damping have you achieved compared to which level? (at listening position)
Did you do a knock by hand? (to get a sonic impression)
Augerpro/Brandon did some measurements but results are frustating!
Maybe the convincing result of the Acoustic Energy AE500 in the video comes from the total 3-layer construction (CLD) for all cabinet walls!?
Of course , for some guys , it depends on the music , to put more effort in making a sound-dead Cab , makes no sense :
A more ear-friendly version :
Please elaborate further ... how much damping have you achieved compared to which level? (at listening position)
Did you do a knock by hand? (to get a sonic impression)
Augerpro/Brandon did some measurements but results are frustating!
Maybe the convincing result of the Acoustic Energy AE500 in the video comes from the total 3-layer construction (CLD) for all cabinet walls!?
Of course , for some guys , it depends on the music , to put more effort in making a sound-dead Cab , makes no sense :
A more ear-friendly version :
This is dampening of air sound waves of material sheets of about 1x2m size.
Red line is the Berger's mass law theoretical value, green line calculated coincidence frequency.
That's the behaviour of the material alone, not an enclosure with bracings or edges or other influences. And it is surprisingly close to the theory
Just to get a feeling how much different materials differ.
I also did some controlled "knock" tests but they pretty much tell the same as you see in the fr.
Red line is the Berger's mass law theoretical value, green line calculated coincidence frequency.
That's the behaviour of the material alone, not an enclosure with bracings or edges or other influences. And it is surprisingly close to the theory
Just to get a feeling how much different materials differ.
I also did some controlled "knock" tests but they pretty much tell the same as you see in the fr.
Erin and his holy Klippelizer could answer your questions making a measurement of the unwanted , hidden "shadow response" ... www.erinsaudiocorner.com
This measurement with electrically reversed 2nd speaker (front-to-front mounted with elestic seal in between) has the disadvantage of a cancellation effect where the output of both speakers are out of phase in the far field . Due to unknown high-Q vibration modes spaced around the Cab , probably even at different frequencies the resulting sum is hard to estimate!
We can speculate that a "noise" level of that unwanted sound is typically around minus 20dB for a simple Cab , better Cabs show 30dB difference and good/sufficent Cabs have 40dB reduction!
Some sound vanish thru the Cone and that suspicious rubber thingy , to the outside , quite high in level as Augerpro/Brandon (Chief Howlin' Wolf g) has already measured!
Listen to DIY researcher Brandon around 07:53 where he tries to mimic the sound that goes to the outside , here :
This measurement with electrically reversed 2nd speaker (front-to-front mounted with elestic seal in between) has the disadvantage of a cancellation effect where the output of both speakers are out of phase in the far field . Due to unknown high-Q vibration modes spaced around the Cab , probably even at different frequencies the resulting sum is hard to estimate!
We can speculate that a "noise" level of that unwanted sound is typically around minus 20dB for a simple Cab , better Cabs show 30dB difference and good/sufficent Cabs have 40dB reduction!
Some sound vanish thru the Cone and that suspicious rubber thingy , to the outside , quite high in level as Augerpro/Brandon (Chief Howlin' Wolf g) has already measured!
Listen to DIY researcher Brandon around 07:53 where he tries to mimic the sound that goes to the outside , here :
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