Hi ! thank you very much for your valuable advice
Before answering to your helpful comment i would like to point out that i have come to the conclusion that the front baffle is the real suspect
Therefore i would expect more effort for analyzing its behaviour by measurements Instead they place accelerometers anywhere but on the FB
why not on the reviewer head then the head movement can change the perception of the sound
seriously the FB is the key panel to investigate
thanks a lot These arguments are very important for the design process
I was even thinking to something very extreme i.e. no baffle at all
If we take a woofer and bolt it to a pipe of the same size of the woofer basket there will be almost no baffle
a very stiff pipe will be needed clearly
The 2nd best solution could be a cabinet developed in the depth direction with very little surface around the woofer
a much worse situation could be a situation like the one below
i.e. a very extended baffle
" If we take a woofer and bolt it to a pipe of the same size of the woofer basket there will be almost no a very stiff pipe will be needed clearly "
The B&W people have already used your idea, and applied it individually for each driver. I haven't been lucky enough to hear them, but I bet they don't sound "boxy" at all.......
The B&W people have already used your idea, and applied it individually for each driver. I haven't been lucky enough to hear them, but I bet they don't sound "boxy" at all.......
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Hi thank you very much for your very valuable reply I am trying to put different pieces of info together
One comment in particular struck my mind Even an open baffle speaker can sound boxy even if it doesn't have a box at all
So the only surface that can create the feeling of a boxy sound must be the front baffle
So the design and execution of front baffle is the really critical panel in the end
if we reduce the front baffle area to minimum terms or even eliminate it, it will be a step forward towards eliminating the boxy effect
I would add that if one needs volume it is better to obtain it in depth rather than in width and height
One comment in particular struck my mind Even an open baffle speaker can sound boxy even if it doesn't have a box at all
So the only surface that can create the feeling of a boxy sound must be the front baffle
So the design and execution of front baffle is the really critical panel in the end
if we reduce the front baffle area to minimum terms or even eliminate it, it will be a step forward towards eliminating the boxy effect
I would add that if one needs volume it is better to obtain it in depth rather than in width and height
Hello ginetto61
The front panel (which has always been called "Baffle" (which many incorrectly apply to the whole box, which is an acoustic cabinet or enclosure) fulfills, as you know, the function of eliminating the acoustic short circuit of the front and rear waves radiated by the speaker cone. By adding a "box", that volume of air inside it will help increase the SPL and also extend the reproduction of the low frequencies. You eliminate the short circuit and add two advantages. The bigger it is, the better. You already know the famous rule that you can't have everything, always only two of the three variants. Size, bass extension and volume (SPL) The sealed cabinet will not take advantage of the rear wave as the bass reflex does, each system has its pros and cons. All this is perfectly studied and with mathematical formulas that today are easy to apply, thanks to computing. So to be honest, I don't understand why you keep looking for some "new" method to eliminate the sound that You consider it "square". There are people (I think it was in a Spanish forum) who have tried to copy the Nautilus design. The effort was titanic but I don't think they have even come close to the original sound. Not everything is copying, the Nautilus speakers surely have special characteristics to work in those "snails". So the design of the speaker "container" in space is decisive for the type of sounds you want. Maybe the infinite speaker meets your expectations, but you need permission from the other inhabitants if you share a home, because you need two rooms for it to work optimally.... 😉
https://audiojudgement.com/types-of-enclosures-which-is-the-best/
The front panel (which has always been called "Baffle" (which many incorrectly apply to the whole box, which is an acoustic cabinet or enclosure) fulfills, as you know, the function of eliminating the acoustic short circuit of the front and rear waves radiated by the speaker cone. By adding a "box", that volume of air inside it will help increase the SPL and also extend the reproduction of the low frequencies. You eliminate the short circuit and add two advantages. The bigger it is, the better. You already know the famous rule that you can't have everything, always only two of the three variants. Size, bass extension and volume (SPL) The sealed cabinet will not take advantage of the rear wave as the bass reflex does, each system has its pros and cons. All this is perfectly studied and with mathematical formulas that today are easy to apply, thanks to computing. So to be honest, I don't understand why you keep looking for some "new" method to eliminate the sound that You consider it "square". There are people (I think it was in a Spanish forum) who have tried to copy the Nautilus design. The effort was titanic but I don't think they have even come close to the original sound. Not everything is copying, the Nautilus speakers surely have special characteristics to work in those "snails". So the design of the speaker "container" in space is decisive for the type of sounds you want. Maybe the infinite speaker meets your expectations, but you need permission from the other inhabitants if you share a home, because you need two rooms for it to work optimally.... 😉
https://audiojudgement.com/types-of-enclosures-which-is-the-best/
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Hi thank you for the very kind and valuable advice
I am sure that speakers that absolutely don't sound boxy exist
I would only like to know what makes them sounding not boxy
That boxy feeling is just not acceptable
I think I have found in the baffle design and build the key factor
From what I have read learned and watched the best baffle could be very rigid with some kind of damping
Like a turntable plinth for instance
staying on speaker a very interesting solution imho for baffle is the one of the epos es11
it should be very rigid Plastic is not the very best material Something similar but in metal with the spaces filled with a resin should be fantastic
i have seen a turntable plinth made in cast iron and with acrylici filling of those chambers
I am sure that speakers that absolutely don't sound boxy exist
I would only like to know what makes them sounding not boxy
That boxy feeling is just not acceptable
I think I have found in the baffle design and build the key factor
From what I have read learned and watched the best baffle could be very rigid with some kind of damping
Like a turntable plinth for instance
staying on speaker a very interesting solution imho for baffle is the one of the epos es11
it should be very rigid Plastic is not the very best material Something similar but in metal with the spaces filled with a resin should be fantastic
i have seen a turntable plinth made in cast iron and with acrylici filling of those chambers
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Paul Carmody discusses boxy sound on his Sunflower design website:
https://sites.google.com/site/undefinition/dipole-and-open-baffle/diy-sunflowers?authuser=0
https://sites.google.com/site/undefinition/dipole-and-open-baffle/diy-sunflowers?authuser=0
Hi ! thank you for the very interesting link Nice design indeed But i prefer a two cabinets design one cabinet for the woofer and one for the midhigh section Mostly because the boxyness comes from cabinet resonances Splitting a full range speaker in two cabinets should help in controlling these resonances
Fwi have learned the goal is to move them outside the drivers range Making the bass box stiff will move the resonances up in frequency
Making the midhigh cabinet heavy will move the resonances down in frequency
Some kind of decoupling in the middle could be required Nothing impossible
I also think that it could be helpful to keep the baffle surface to a minimum
Fwi have learned the goal is to move them outside the drivers range Making the bass box stiff will move the resonances up in frequency
Making the midhigh cabinet heavy will move the resonances down in frequency
Some kind of decoupling in the middle could be required Nothing impossible
I also think that it could be helpful to keep the baffle surface to a minimum
You think.
For ideal flat half space response there would be no edges with diffraction.
The baffle would be = infinite. Very much the opposite of making it as small as possible.
Infinite Being impossible, the only alternative is making the baffle = LARGE as possible.
Being there would eventually be diffraction from edges even from a large baffle.
The speaker is offset or not mounted centered in a very LARGE baffle.
To reduce edge diffraction even further.
To be specific for Ideal and standard IEC measurements
Or Speaker companies that spend millions to engineer speakers.
Wanting the most accurate measurement of hard spent money and time.
IEC baffle is 1350 x 1650mm or close to 53" x 65" inches
The driver is not mounted centered to further reduce edge diffraction.
Diffraction is eliminated to almost below 100 Hz
That would be engineers and manufactures looking for the flattest most accurate response
with no diffraction.
Of course " Audiophiles" have taking it to the opposite spectrum.
They make the baffle as " small" as possible to make the response as poor and non flat as possible.
Making sure " edge diffraction" is as worst as possible by placing the edge as close as possible to the driver.
Placing the edges close to the driver as possible, might as well make it worse by making sure to center the
driver on the baffle with no offset. To make that edge diffraction even worse.
Of course you can " make up" or "imagine" theories like the rest of the Diy world.
Or you just brace the box, then add absorption material. Since "boxy" sound is reflected midrange peaks.
And is easily eliminated with light lining. Since high frequency absorption is rather easy to get.
The wavelengths are actually rather small, and rather low pressure.
Otherwise the box sound goes away if you remove the baffle and box,
Then basically everything is cancelled. Except for any worthless directionally bandwidth
which is blocked by the speaker cone itself. Otherwise if the speaker was physically non existent ( impossible)
then no baffle no box. You would have complete cancellation = nothing
Make sure to indulge in the worst possible. Small baffle for worst response, edges close to driver
for worst diffraction. All else fails just remove the box and cancel even more. YAY!!!
For ideal flat half space response there would be no edges with diffraction.
The baffle would be = infinite. Very much the opposite of making it as small as possible.
Infinite Being impossible, the only alternative is making the baffle = LARGE as possible.
Being there would eventually be diffraction from edges even from a large baffle.
The speaker is offset or not mounted centered in a very LARGE baffle.
To reduce edge diffraction even further.
To be specific for Ideal and standard IEC measurements
Or Speaker companies that spend millions to engineer speakers.
Wanting the most accurate measurement of hard spent money and time.
IEC baffle is 1350 x 1650mm or close to 53" x 65" inches
The driver is not mounted centered to further reduce edge diffraction.
Diffraction is eliminated to almost below 100 Hz
That would be engineers and manufactures looking for the flattest most accurate response
with no diffraction.
Of course " Audiophiles" have taking it to the opposite spectrum.
They make the baffle as " small" as possible to make the response as poor and non flat as possible.
Making sure " edge diffraction" is as worst as possible by placing the edge as close as possible to the driver.
Placing the edges close to the driver as possible, might as well make it worse by making sure to center the
driver on the baffle with no offset. To make that edge diffraction even worse.
Of course you can " make up" or "imagine" theories like the rest of the Diy world.
Or you just brace the box, then add absorption material. Since "boxy" sound is reflected midrange peaks.
And is easily eliminated with light lining. Since high frequency absorption is rather easy to get.
The wavelengths are actually rather small, and rather low pressure.
Otherwise the box sound goes away if you remove the baffle and box,
Then basically everything is cancelled. Except for any worthless directionally bandwidth
which is blocked by the speaker cone itself. Otherwise if the speaker was physically non existent ( impossible)
then no baffle no box. You would have complete cancellation = nothing
Make sure to indulge in the worst possible. Small baffle for worst response, edges close to driver
for worst diffraction. All else fails just remove the box and cancel even more. YAY!!!
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I think, Siegfried Linkwitz was on the same search as you are.
Take a look at https://linkwitzlab.com/
I am on my way building a Lxmini after I heard a Lx521. Greatest spatial sound reproduction I ever expierenced.
Take a look at https://linkwitzlab.com/
I am on my way building a Lxmini after I heard a Lx521. Greatest spatial sound reproduction I ever expierenced.
That's already all of the phenomenon, for me. A poorly tuned Bass-Reflex can provide that kind of unpleasant sound - among other...
I'll cite a personal experience while I was in search of pair of small bookshelf speakers...
I went first for the Klipsch R-14M... How cute they are !
But how BOXY they sound too ! Simply awful... Nearly a caricatural example !😱
The filling was quasi-nonexistent, so first I corrected this point :
Then I lowered the tuning of the box, to escape the boxy hump :
This removed that BOXY sound = lower midrange coloration (as stated by @mattstat) without killing the bass. The mod "removed a mask of false bass", if I can say so... 😎
I do not have them anymore : not worth, except the tweeter. After listening, the Guy who bought them preferred the modded version, so I sold them as is... He absolutely wanted a small pair of Klipsch, so everybody was happy ! 😊
Then I went for a pair of Tangent EVO-4 like new, unused. No boxy sound with these little sealed enclosures, nor tonal imbalance : I keep them !
So yes, for me boxy sound is indeed and primarily related to the enclosure design, that is to say box and speaker. The room, the placement and other factors rank second, because they can rather degrade than improve the management of the existing boxyness coming from the enclosure by itself...
But it's me, OK ? 🙂😉
T
Hi thank you very much for your valuable advice If i understand well you associate boxyness to diffractions from edges ?
so this is quite different from cabinet resonances i am not worried very much about diffractions Some felt strategically placed around the drivers could solve the problem Resonances are more challenging
I think i have found a viable solution The nastier ones are those generated by the woofer because they have more energy
A smart way could be to use a rigid cabinet for the woofer so that resonances will move up in Hz and outside the range covered by the woofer
for the mid-high section (the head) a heavy cabinet should work moving the resonance down in Hz outside the range covered by the head
The decoupling between the head and the body could be realized with material like the SYLOMER
i see But i am not sure that a flat response should mean no boxyness
i guess that some distortion or CSD measurements could be more telling about the presence of resonances
the problem is that the baffle could be a key element for resonances in the sense that baffle resonances could be the worse for boxyness (i would call it boxymess)
therefore reducing the baffle surface to a minimum could be a very smart way to reduce the key cause of resonances
I remember some original speakers with no baffle at all
if the concept works it could be scaled up and down i.e. three cabinets of the same type and different size to accomodate woofer mid and tweeter
i see anothe speaker with very small baffle and combining mid and tweeter
maybe i am underestimating the problem but i see diffractions much easier to eliminate As i said above felts or long hair carpets around the drivers could be the solution The sound will never reach the edges Some experiments are needed of course But i am optimistic
add bracing increase stiffness Regarding absorption materials i have seen video of damping materials used on metal sheets that make them very dead acoustically
i cannot be worried by diffractions because i am sure there are easy ways to deal with them
You can always prevent sound to reach any edges at least with dome drivers With absorption rings or lenses or little horns or waveguide
But resonances are more dangerous imho
hi thank you very much I can notice that the baffle on the mid high section in the LX521 is reduced to a minimum
a see also a separate cabinet dedicated to the woofer I wonder if some kind of mechanical decoupling has been used between the two parts
this is very interestin and what triggers my motivation Spatial sound completely detached from speakers Very very nice
I will study the link carefully Thanks again
This happens with other types of speaker too when done right.
yes, the top baffle is decoupled. Look at the attached picture.
Or here:
https://oplug-support.org/viewtopic.php?f=28&t=5714
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I eliminated the "boxy" coloration of the sound on several factory speakers by gluing bitumen sheets to the sides and adding damping to the box. Sometimes it is enough to add only damping to the box, say polyester wadding on all sides except the front. I fixed one SUB (Monitor Audio ASW100) by adding a pyramidal sponge.
Care should be taken with the crossovers, if there are resistors on them that heat up, the wadding must be cut there. If there are any electronics in the speakers, that part must not be covered.
OB speakers and other dipole speakers (planar) cannot sound "boxy" because they do not have a box in which to generate standing waves and resonances. Some types of loading have resonances, Ripol, H dipole, etc.
Care should be taken with the crossovers, if there are resistors on them that heat up, the wadding must be cut there. If there are any electronics in the speakers, that part must not be covered.
OB speakers and other dipole speakers (planar) cannot sound "boxy" because they do not have a box in which to generate standing waves and resonances. Some types of loading have resonances, Ripol, H dipole, etc.
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Hi ! thank you very much for the help Finally I am beginning to see the light
1) bass woofer of about 10" in a dedicated rigid cabinet
2) mid-high section with minimized baffle around the drivers and very rigid and heavy
then it is clear the crossover will come but it worries me much less
It is not the crossover that makes the loudspeaker disappear but the design and construction of its cabinet I am completely sure of it
I believe that a three-way with a good 10" woofer could cover well from 50 to 15k A nice portion of the spectrum
Now I only still have some doubts about how to make the woofer cabinet to be able to access the inside easily
I don't know if the removable upper part or the lower one is better
I think it doesn't make much difference
What i would call boxy is mostly wrong higher bass response. It can be caused by a resonating cabinet (can be avoided by bracing the cabinet right and use the right wood of the right thickness, or damping in the form of CLD) or wrong tuning of the woofer (crossover, cabinet format). But it can also be the room with heavy room modes (where dsp and acoustic treatment can help). There are a lot of possible reasons of this. What it is in your case is what you need to find out yourself, and often it's even a combination of factors.
Hi ! thank you very much for your very interesting advice
I have been advised to get a high stiffness for the bass cabinet in order to move resonances up in frequency and therefore outside the working range of the woofer
I guess i will have to buy a cheap signal generator to check the behaviour of the cabinet
A very easy test would be to place a small jar with water above the cabinet and make a low Hz sweep at high level
like they did in this video
At least, a rather flat response means that you don't have to wait for a hump in the low-midrange area, which is already a good point... But frequently, boxyness can be identified by such kind of accident in the frequency response, and even sometimes in the impedance curve.
T