@ academia50
I've pinged the mods to do that for you
Very thanks, friend !
Merry Christmas
Done
(If you want anything changing then use the report post option, that way we are sure to see it)
Very thanks !
I do not understand how that possibility did not occur to me ...
Send an MP to the moderators directly ....
Since I know that now you will read this, I have one more doubt, how is it done to attach a preferred phrase at the bottom of each post ?
I have tried it in several ways, exploring the options in my profile, but it has been useless, I can not find it.
Merry Christmas friend !
Very thanks Mooly !, step by step how to proceed and with the pics, excellent !
As I mentioned before, there will be two reinforcements. A small advance on these holidays and with more rain around here .....
The construction of a template to then cut all panels exactly the same, is a simple and traditional method in carpentry work.
Use thin boards, and each angle should be secured with two nails (they can be more, but two is enough, they should be thin, otherwise the wood will crack, (you know, do what I say, not what I do... ) then bend the nails on the back and the template will not move.
The speaker will go to the bottom of the box, and the reinforcements will be distributed in the remaining space.
The construction of a template to then cut all panels exactly the same, is a simple and traditional method in carpentry work.
Use thin boards, and each angle should be secured with two nails (they can be more, but two is enough, they should be thin, otherwise the wood will crack, (you know, do what I say, not what I do...
) then bend the nails on the back and the template will not move.The speaker will go to the bottom of the box, and the reinforcements will be distributed in the remaining space.
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Hi, maybe I should tell you the truth about your project. The speaker you have is a PA woofer, not a Hifi Sub woofer. Meant for loud reproduction, not lower than 40 Hz. In a large, vented box of about 500 liters.
Less volume with this speaker means even less low bass.
When you started here, there where 300 liters volume. Not very much for your speaker, if you want to use this small, childish plate amp. You maybe would have gotten a good woofer, but no sub with low frequency response.
Then you divided the volume by 2: makes 150 Liters.
This gives no bass at all, only a midd woofer. The plate amp is absolutly lost in this configuration.
So, this is dead born in all aspects. Sorry, but that is the sad truth. You ignore physics and the since of loudspeaker building. You wast your time and money.
Less volume with this speaker means even less low bass.
When you started here, there where 300 liters volume. Not very much for your speaker, if you want to use this small, childish plate amp. You maybe would have gotten a good woofer, but no sub with low frequency response.
Then you divided the volume by 2: makes 150 Liters.
This gives no bass at all, only a midd woofer. The plate amp is absolutly lost in this configuration.
So, this is dead born in all aspects. Sorry, but that is the sad truth. You ignore physics and the since of loudspeaker building. You wast your time and money.
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If you take two triangles and move them around, there is a configuration that gives a triangle twice the size. Maybe think about it. Then you need an amplifier that has enough power to drive you loudspeaker sub resonance, minimum 800 watts at 8 ohm with not more than 1% distortion.
Next a device to reshape the signal, so it does correct the lower cone movement with low notes.
Last, the enclosure has to resist the under and over pressure produced by the loudspeaker. Your little pieces of wood are absolutly useless. Take stripes of 18mm MDF about 10cm high and glue them to all panels, at 25cm distance, like a T-bar.
That might work. Maybe I find a picture to give you an idea.
Next a device to reshape the signal, so it does correct the lower cone movement with low notes.
Last, the enclosure has to resist the under and over pressure produced by the loudspeaker. Your little pieces of wood are absolutly useless. Take stripes of 18mm MDF about 10cm high and glue them to all panels, at 25cm distance, like a T-bar.
That might work. Maybe I find a picture to give you an idea.
Here is a good example how you build a subwoofer enclosure:
If you have lower expectations, maybe take only half of the bracing. But you will feel the difference, when the woofer plays and you place your finger on its outside.
As a rule of thumb the bracing shall be 5x the stength of the panel you want to enforce. So for 20mm make them 10cm high, 18mm gives 9cm...
If you have lower expectations, maybe take only half of the bracing. But you will feel the difference, when the woofer plays and you place your finger on its outside.
As a rule of thumb the bracing shall be 5x the stength of the panel you want to enforce. So for 20mm make them 10cm high, 18mm gives 9cm...
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I understand what you want to say, they are reasonable arguments.
Do not worry, what you say is not a sad reality for me at all.
If you look at my simulations with WINISD published above, you will see that 20 hertz: - 19 db, 30 hertz - 13 db, and 40 hertz - 8db with respect to the maximum output of the speaker.
It's not extraordinary, right? but it's what I need to cover in my sound network the first octaves and the kiddie (hey, that was really hard, I hope the people of Dayton do not read this!) plate amplifier has enough power for a familiar environment, I know because at the moment I'm using two vintage JBL speakers of 80 liters each and 14 inches, (you should read the whole cartoon, ha) and they are giving me what I'm looking for, only that they are limited in the admission of power and Xmax with regarding the Eminence that I will use.
I appreciate your sincerity, but your comments point to different goals than mine ...
Attached you can see the Eminence projects that they have for this speaker. I could add ports to upload SPL, (no, no, no, I prefer to buy a Bheringher Inuke with DSP in the future, but I know it will not be necessary) but I look for the best response in transient sounds from a sealed cabinet. And the biggest cabinet of them is 10 cubic feet, 283 liters, you do not need 500.
Eminence says it: Long throw subwoofer for very small
vented boxes
https://www.eminence.com/pdf/Delta_Pro_18A_cab.pdf
Do not worry, what you say is not a sad reality for me at all.
If you look at my simulations with WINISD published above, you will see that 20 hertz: - 19 db, 30 hertz - 13 db, and 40 hertz - 8db with respect to the maximum output of the speaker.
It's not extraordinary, right? but it's what I need to cover in my sound network the first octaves and the kiddie (hey, that was really hard, I hope the people of Dayton do not read this!) plate amplifier has enough power for a familiar environment, I know because at the moment I'm using two vintage JBL speakers of 80 liters each and 14 inches, (you should read the whole cartoon, ha) and they are giving me what I'm looking for, only that they are limited in the admission of power and Xmax with regarding the Eminence that I will use.
I appreciate your sincerity, but your comments point to different goals than mine ...
Attached you can see the Eminence projects that they have for this speaker. I could add ports to upload SPL, (no, no, no, I prefer to buy a Bheringher Inuke with DSP in the future, but I know it will not be necessary) but I look for the best response in transient sounds from a sealed cabinet. And the biggest cabinet of them is 10 cubic feet, 283 liters, you do not need 500.
Eminence says it: Long throw subwoofer for very small
vented boxes
https://www.eminence.com/pdf/Delta_Pro_18A_cab.pdf
I think you confuse the templates with the true bracings, the photos are of only a "mold" ....
And will not they be useless, all help, or do you want me to do something like that?
The mother of all subwoofers build
This construction is for me a bit of fun too, it does not have to become a torment, when I built the DTQWTII cabinets of Troels I already suffered too much !
Help and a lot !
The deflector supports the speaker and transmits its vibrations physically, not only by the pressure waves of the air generated by the speaker's diaphragm....
I found this that would seem to confirm that the series capacitor would help to raise the level of the lowest frequencies ..
mmmmmmmmmmmmm .....................
Strassacker: Speaker Building, Components
I think that this paragraph that I have highlighted in bold deserves a strong response from me.
Here you can see that in 20 hertz, (remember that this project is to enjoy music exclusively, not for HT nor to use in those places where young people go - I hope you are not one of them, turbowatch - to destroy their ears and your brains with a lot of alcohol, marijuana and / or other substances) the difference between the cabinet of 150 liters and 300 liters is 3 db, that is, you would need to double the power in watts to achieve the same SPL, right?
Well, then, do not you think two speakers compensate that loss? , - besides other advantages to have two cabinets subwoofers instead of one, which is not the case to explain now ..... - Your reasoning is based on only one box and also do not take into account aspects such as room gain, location of the cabinets, etc.
You must inform yourself better before giving such bad news, and let me tell you that
"The dead that you kill, enjoy good health"
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Building the reinforcements .
Now I must decide the number and size of the holes, I am hesitating between a single large or three small, I will have to calculate the surfaces of the circles ....
Someone remember how to calculate this ?
Now I must decide the number and size of the holes, I am hesitating between a single large or three small, I will have to calculate the surfaces of the circles ....
Someone remember how to calculate this ?
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Circle CalculatorAccording to the calculation of the surface of each circle and with the commitment not to weaken it, go six holes for each bracing.
Each of them will be 8.6 cm in diameter, and an area of 58.09 cm2, which will give a total of 348.54 cm2
Here a simulation with glasses .....
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I have tried with one more circle, there will be seven and this will take the total surface of air passage between the different compartments to 406.63 Cm2.
I believe that being a sealed cabinet is best to maximize the uniformity of air pressure within it.
Being a prism, (a box shape much stronger than a parallelepiped) there will be no major difference in the strength of the bracings .
I believe that being a sealed cabinet is best to maximize the uniformity of air pressure within it.
Being a prism, (a box shape much stronger than a parallelepiped) there will be no major difference in the strength of the bracings .
you may find the placement, will provide you the gain at the lower frequency's. so I would try it as it is, then perhaps see about trying a capacitor.
I did notice it sky rockets the diagram displacement so It might be better left out.
room gain with some eq boost at the lower frequency should be fine for your wants. is it quite a large room?
I did notice it sky rockets the diagram displacement so It might be better left out.
room gain with some eq boost at the lower frequency should be fine for your wants. is it quite a large room?
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