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J-Bolts might help too. You can use them to hook the basket and pull it towards the wooden frame. Your aproach does look more elegant than H-Frames.
J-Bolts might help too. You can use them to hook the basket and pull it towards the wooden frame. Your aproach does look more elegant than H-Frames.
Great idea!
I bear that in mind if the current solution proves to be inadequate.
Or perhaps I´ll apply them anyway, just to be on the safe side.
On the other hand, they will constitute more "air resistance" for the backward wave.
Currently I only have the centre baffle attached, not the side wings that is (see picture in #23), to get a greater openness for the backward airflows.
One rule of thumb states 10 x Vas of free space behind the baffle, so that would be 15 cubic meters per side. I have only got 10 cubic meters in total, so it got a little bit stuffy.
The grin got bigger with this change of set-up.
One rule of thumb states 10 x Vas of free space behind the baffle, so that would be 15 cubic meters per side. I have only got 10 cubic meters in total, so it got a little bit stuffy.
The grin got bigger with this change of set-up.
I don´t think that the nail strips serves any purpose other than being a safety precaution for any slow or fast moving sideway force knocking the elements out of their cradles.
In sweet spot, I don't see them so why make them more elegante?
However, having the Soul Sonic speakers in mind, a 4 or 6 mm akrylic glass as baffle would definitely call for some more elegance, and then it won't stop with the strips. Then the Elegance not only be Acoustic but also Visual.
In sweet spot, I don't see them so why make them more elegante?
However, having the Soul Sonic speakers in mind, a 4 or 6 mm akrylic glass as baffle would definitely call for some more elegance, and then it won't stop with the strips. Then the Elegance not only be Acoustic but also Visual.
Is your construction adequate?
I had a set of 18 inch drivers and a set of 15 inch drivers in open baffle (one each per side), and I had a hard time keeping the drivers from shaking the supports/baffles to death. Do you listen to your music at low levels, or are you high passing the woofers? With that much mass moving back in forth, it would seem that your setup would not be sufficient, especially for the drivers mounted up that high.
Also the cancellation dramatically reduces the response at lower frequencies, particularly since your baffle is relatively small. Thus, it would seem that you will have a lot of movement without a lot of low end. Is this correct?
I had a set of 18 inch drivers and a set of 15 inch drivers in open baffle (one each per side), and I had a hard time keeping the drivers from shaking the supports/baffles to death. Do you listen to your music at low levels, or are you high passing the woofers? With that much mass moving back in forth, it would seem that your setup would not be sufficient, especially for the drivers mounted up that high.
Also the cancellation dramatically reduces the response at lower frequencies, particularly since your baffle is relatively small. Thus, it would seem that you will have a lot of movement without a lot of low end. Is this correct?
Just did some checking on the output power at my "0 dB" line level at the "low end".
Each woofer, that has its own amplifier, is then feed with 25 W and gives 105 dB of sound pressure in the near field. It's hard to tell the excursion, but let's say it is +/- 5 mm. The mms of 153 grams moving back and forth then reacts with the woofer (10 kg) and one third of the support (10 kg). That gives a relation of 130, it is a little bit on the low side, considering the rule of thumb of 1000. No audible problem or any vibration problem with that though.
Perhaps because all the counter weight is right behind the cone and with no sound wave induces vibrating surfaces.
The support is on 10 pieces of 15 mm in diameter and 10 mm high rubber feet.
The baffle is totally decoupled from the woofer/support, well apart from the floor coupling and the actual sound waves.
My listening levels tends to be between -9 dB and -2 dB relatively my "0 dB", so I´d say I´m on the safe side.
I understand your doubts, what's your listening levels?
Each woofer, that has its own amplifier, is then feed with 25 W and gives 105 dB of sound pressure in the near field. It's hard to tell the excursion, but let's say it is +/- 5 mm. The mms of 153 grams moving back and forth then reacts with the woofer (10 kg) and one third of the support (10 kg). That gives a relation of 130, it is a little bit on the low side, considering the rule of thumb of 1000. No audible problem or any vibration problem with that though.
Perhaps because all the counter weight is right behind the cone and with no sound wave induces vibrating surfaces.
The support is on 10 pieces of 15 mm in diameter and 10 mm high rubber feet.
The baffle is totally decoupled from the woofer/support, well apart from the floor coupling and the actual sound waves.
My listening levels tends to be between -9 dB and -2 dB relatively my "0 dB", so I´d say I´m on the safe side.
I understand your doubts, what's your listening levels?
Being inspired by Forsman D2/10 dipole speakers , I'm currently tempted to do something about the elegance m R g S r pointed out earlier.
So it is all about making curved, that is ellipsoidal, baffles in two dimensions lowering the "Q" of the baffle step and the dipole cancellation while maintaining a small footprint.
The acoustic width of the baffle is currently 58 cm wide overall.
It will be 60 to 95 cm but the front baffle will be 40 to 55 cm.
As bonuses, the frequency when the dipole cancellation starts will thus be lowered and the front footprint will actually be less hopefully giving more sound stage.
The side baffles can of course be deeper, but then it will be more or less a H-frame and that's not the design goal.
Here's a mock up of the the idea in 1:10 scale, every square is 5x5 mm.
The model couldn't stand straight:
So it is all about making curved, that is ellipsoidal, baffles in two dimensions lowering the "Q" of the baffle step and the dipole cancellation while maintaining a small footprint.
The acoustic width of the baffle is currently 58 cm wide overall.
It will be 60 to 95 cm but the front baffle will be 40 to 55 cm.
As bonuses, the frequency when the dipole cancellation starts will thus be lowered and the front footprint will actually be less hopefully giving more sound stage.
The side baffles can of course be deeper, but then it will be more or less a H-frame and that's not the design goal.
Here's a mock up of the the idea in 1:10 scale, every square is 5x5 mm.
The model couldn't stand straight:
Miscalculation
It should be:
The mms of 129 grams moving back and forth then reacts with the woofer (10 kg) and one third of the support (10 kg). That gives a relation of 155, it is a little bit on the low side, considering the rule of thumb of 1000
It should be:
The mms of 129 grams moving back and forth then reacts with the woofer (10 kg) and one third of the support (10 kg). That gives a relation of 155, it is a little bit on the low side, considering the rule of thumb of 1000
I never understood that rule of thumb....really. If there is a mere 1:10 relation between the cone and the rest, that would only mean you loose half a dB of output. Of course the box will move, but really not all that much. Just make sure you suspend it properly from the floor, and there is no problem at all.
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