More precise: virtually without panel resonances. Most vibrations in a enclosure are not set up by pressure differentials; 99 % is caused by reaction forces. Deal with those first.
Hi thank you very much indeed I like the horn option a lot I have the feeling that in an acoustically non-treated room to have a controlled dispersion can be a good thing More and more pro studio monitors adopt some kind of lenses or horns
I guess that a less resonant material could add less distortion ? someone swear about that
i also like this solution a lot ... like a scaled down Altec VOTT
Nice speakers indeed I have already heard about those But the external horns is very fascinating I think that in this case the lens is integrated in the baffle
But nice anyway
Thanks a lot This confirms my feeling And i see wood used almost always for DIY projects There must be a reason
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Hi very interesting If you have to design a bass cabinet with just one bass drivers at what level of weight you would think ?
Is there an optimum ratio between speaker mass and driver moving mass ? i heard some figures that shocked me deeply ... like thousands times
Lately i have become obsessed with heavy weight A lot I would like to avoid counter moving bass drivers
There is no way to stop reaction forces by mounting a large weight. There simply always will be some counter movement. I have picked up the reaction forces of a dome tweeter on the rear of loudspeaker enclosures by means of an accelerometer.
It all depends on the enclosure shape and construction to what extent these counter movements will lead to resonances, and to what extent these resonances will lead to audible phenomena.
In view of all these variables, there is no correct answer that will apply to all situations.
It all depends on the enclosure shape and construction to what extent these counter movements will lead to resonances, and to what extent these resonances will lead to audible phenomena.
In view of all these variables, there is no correct answer that will apply to all situations.
I wonder what level of vibrations have you measured As an example a Dynaudio D28 has a moving mass of only 0.53 g ... that is nothing
https://site.diy-loudspeakers.com/i...speakers/dynaudio/TWEETERS/DYNAUDIO_D28v2.pdf
in the stereophile tests they usually stop the measurements with accelerometers at around 2 kHz, so still in the midrange
I guess because above that there is nothing to measure at all
Anyway if you tell me that exciting the speaker with test signals above 2 kHz you still get vibrations i believe you
Imho the only vibrations really detrimental for sound are those that cause the front baffle to move back and forth (if the tweeter is mounted on it of course)
Fwiu at B&W they use laser interferometry to check for any micromovements of the front baffle in particular My feeling is the matrix concept is very efficient in avoiding this phenomena
And if you look at the weight of even the 801 1st edition is substantial even with the extended internal bracing (Weight: 49kg with the newer versions twice this)
Because any little movement of the front baffle shifts the sound point source in the tweeter And the sound image wavers consequently
Incidentally the speakers with the best image have all thick stiff heavy baffles You should try the accelerometer on the front baffle ... the others are not important
Moreover I am quite sure that if you take out the tweeter from a normal 2 way box and mount it in a separate heavy block isolated mechanically from the bass box the soundstage will get better More focused
Ginetto, I bought this kit a while ago https://www.diyaudio.com/community/threads/accelerometer-testing-of-loudspeaker-drivers.267734/
It really works great, believe I did measurements at 2 kHz. It produced some remarkable results.
Hifijim, thanks. When you in the neighbourhood, please drop by for a listening test. It is an open invitation to others who are interested as well, of course.
It really works great, believe I did measurements at 2 kHz. It produced some remarkable results.
Hifijim, thanks. When you in the neighbourhood, please drop by for a listening test. It is an open invitation to others who are interested as well, of course.
hi thank you so much for the link
i will try to get one because it is very valuable to me
still I don't understand why not putting the accelerometer on the front baffle
i read a very telling comparison
consider the front baffle as a page of a newspaper
then ask someone to keep it still in front of you and read
then ask the same person to move the page back and forth and try to read again
to keep the focus on the letters will much more difficult
i am sure that any movement of the front baffle would be so much more detrimental to sound than any other side of cabinet movement
Moreover i have no precise information but i am pretty sure that at b&w when they use laser interferometry to check for any cabinet vibrations they place the measurement mirror only on the front baffle
If i am wrong i would love to know
you have also to consider that side panels vibrations will reach the listener only after reflection with the side wall
what we hear as reflections are the reflections generated by the drivers not the cabinet panels
an absolutely still front baffle is the key for great soundstage imho