Stig Erik, as an Orion owner I have major rattle issues with the baffle on loud double bass passages, I need to rebuild it completely, and more seriously..the XO is 92hz, and there is already a delay on the XO that could be changed, I shall try to check the corner placement.. that could kill two birds with one stone!
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My CLIO is 20 years old, and I really shouldn't expect a 20 year old harddrive to last forever ..... 🙁
Yet an other good reason to separate the bass from the rest. 😉
In my opinion, the XO point on the Orion is too low, considering that the dipole peak of the midrange baffle is somewhere around 5-600 Hz. The distortion of the W22 also starts to rise significantly below 150 Hz even at a couple of watts measured in closed box, and that will be much worse in an open baffle. I dont know if anyone has tried to alter the XO point, but it would be interesting to try 200 or 250 Hz.
well, the XO was 120hz initially, before the last revision.. it would indeed be great to play with it, but that requires a parallel digital XO.. can one implement the massive boost on the woofers that way?
regarding the vibrations, yeah, a dipole does not kill them, far from it, the more cone movement makes things worst actually.. unless you use some force cancellation arrangement, and even so..
regarding the vibrations, yeah, a dipole does not kill them, far from it, the more cone movement makes things worst actually.. unless you use some force cancellation arrangement, and even so..
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I have used up to 40 dB bass boost EQ in the digital domain, and I really dont see any big problems with that as long as you watch your levels and avoid digital clipping.
True - dipoles make vibrations a bigger problem, since the cone moves more and the baffle in general is lighter than a big box. On one of my early designs, the top of the baffle moved almost 1 cm when I cranked it up....
The solution to this is to suspend the baffle in a swing, that is hang it from the ceiling or som kind of frame. It may sound like a bad idea, but it is not.
True - dipoles make vibrations a bigger problem, since the cone moves more and the baffle in general is lighter than a big box. On one of my early designs, the top of the baffle moved almost 1 cm when I cranked it up....
The solution to this is to suspend the baffle in a swing, that is hang it from the ceiling or som kind of frame. It may sound like a bad idea, but it is not.
I tell you what.. my wife is going to hate you, big time! 😎
panels everywhere.. big baffles.. now hanging from the ceiling?! so that's 1, 2...3 trips to Milan? 😉
panels everywhere.. big baffles.. now hanging from the ceiling?! so that's 1, 2...3 trips to Milan? 😉
It sounds interesting. Do you have an issue with twisting modes between the cables?
It was a minor issue when I did this with a 21" woofer that had no baffle. But with a baffle and enough total mass it's not a problem to worry about.
Never made a fullrange dipole, but hanging MF/HF cabs above LF cabs cleaned up the bass amazingly. Xover was active 24dB/oct @ 170Hz. The cabs were pretty heavy, too, so mass loading OBs might stop twisting being a problem. My cabs had 2 cords (cotton shoelaces) each side anyway.
And hanging my kids' 12" Wharfedale cabs from their ceiling worked well too. Literally headbanging though, if too low.
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Deeper is Better (DIB) - makes it more like OB ?
"Some time ago I intentionally made two different boxes for my ScanSpeak drivers to see what will happen, because I do not believe in theories and trust only to my ears. The boxes had exactly the same internal volume and front baffle width, so the only difference was in their actual proportions (height and depth). The first one was very tall and very shallow, the second one was little in height but very deep.
There was HUGE difference in sound. The deep box sounded much more articulated and with ease at the dynamic peaks. The improvement in sound was most remarkable in the upper range of the driver. The only reasonable explanation I have for that is that the back wave form the driver bounce back to the cone and interfere with the front fired wave, adding delayed signal with high amplitude. If the back wall is very far from the driver’s diaphragm, the energy of the reflected wave is very low thus the sound is more clear and better defined. In comparison the sound of the shallow box was some kind of polluted at MF, loosing definition and dynamics (micro and macro), the midbass was quite excessive and unlistenable, although SS is quite nice driver." Petar.
from: GoodSoundClub - Romy the Cat's Audio Site - Sealed, Ported, and Less-than-Ported Summer Listening
"Some time ago I intentionally made two different boxes for my ScanSpeak drivers to see what will happen, because I do not believe in theories and trust only to my ears. The boxes had exactly the same internal volume and front baffle width, so the only difference was in their actual proportions (height and depth). The first one was very tall and very shallow, the second one was little in height but very deep.
There was HUGE difference in sound. The deep box sounded much more articulated and with ease at the dynamic peaks. The improvement in sound was most remarkable in the upper range of the driver. The only reasonable explanation I have for that is that the back wave form the driver bounce back to the cone and interfere with the front fired wave, adding delayed signal with high amplitude. If the back wall is very far from the driver’s diaphragm, the energy of the reflected wave is very low thus the sound is more clear and better defined. In comparison the sound of the shallow box was some kind of polluted at MF, loosing definition and dynamics (micro and macro), the midbass was quite excessive and unlistenable, although SS is quite nice driver." Petar.
from: GoodSoundClub - Romy the Cat's Audio Site - Sealed, Ported, and Less-than-Ported Summer Listening
Bigun ... I tend to think that this persons revelation has more to do with how the driver is acoustically loaded. A shallow box seems to load a driver differently than a deeper box given exact internal volume for both. The same can be said for naked dipoles vs "H" frames vs "U" frames.
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I understand that the loading on the cone is caused by the interaction of the backwave with the cone. So whether the backwave escapes out through the cone, or affects the behaviour of the cone through loading, the end result is colouration. And this colouration is caused by the backwave and it is modified by the shape of the box. Perhaps as one might predict.
What was interesting was the fact that he noticed a big difference. This tells me that people who compare OB to boxes need to note whether they are comparing with shallow or with deep boxes. A deep box gets closer to an IB and this is the direction one might go in order to address the colourations issue.
What was interesting was the fact that he noticed a big difference. This tells me that people who compare OB to boxes need to note whether they are comparing with shallow or with deep boxes. A deep box gets closer to an IB and this is the direction one might go in order to address the colourations issue.
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boy, did you guys follow speaker dave's posts or not? Keeping the internal volume the same, box shape should not make any difference, as long the backwave is fully absorbed. And Dave showed how this can be done. If there was an audible difference, it is only because there was not adequate absorption of the backwave in one of the cases.
The box is doing only two things: separating the front wave from the back wave, and providing loading to the woofer near resonance. The internal volume provides the loading. If the response in each case was corrected for baffle step, the test should reveal no difference.
As a side note, most, if not all, of the stuff on that site is utter rubbish.
The box is doing only two things: separating the front wave from the back wave, and providing loading to the woofer near resonance. The internal volume provides the loading. If the response in each case was corrected for baffle step, the test should reveal no difference.
As a side note, most, if not all, of the stuff on that site is utter rubbish.
I read them too ... David is a sharp cookie.
Was pretty sure it has been stated here that lower frequencies are harder to attenuate. I'm thinking that even if you could completely suppress the rear wave .. .. you do still have a pressure differential on the cone. Just as room dimensions change sound wave propagation .. so does the boxes interior configuration. So the LF interior wave has a signature linked to that box. I'd think changing the box shape would alter the signature.
Wonder if David has any thoughts on his choices of cabinet shape/driver matches?
Was pretty sure it has been stated here that lower frequencies are harder to attenuate. I'm thinking that even if you could completely suppress the rear wave .. .. you do still have a pressure differential on the cone. Just as room dimensions change sound wave propagation .. so does the boxes interior configuration. So the LF interior wave has a signature linked to that box. I'd think changing the box shape would alter the signature.
Wonder if David has any thoughts on his choices of cabinet shape/driver matches?
That's your choice of course, whether to believe someone who's backing his statements with actual science and a career's worth of specialized experience in this field, or believe your own unfounded notions of how things work.
Whatever makes you happy.