So,long story short,i have speaker EMINENCE KAPPA PRO 18LF-8 and i want to make a subwoofer with him.
First idea was to make a horn speker,Wbin,and after big help of some guys here,and discussing diferent types of enclosure,i come to conclusion that maybe is best way to go with ported enclosure.
First i didnt know how to use any software for designing enclosurer but i take time and now i masterd hornresp and winisd 🙂
So after calculating so many diferent designs,conclussion is,if i want to go loooow,and stay in marriage,ported enclosure is the best way. 🙂
I understand that speaker what i have is not the best speaker for what i want to get,but i will try and see what i can get out of him.
So,now the questions.
I make compromise to go max with 400l box,outside dimension,inside 350l.
I make few designs wich look good to my understanding but,im amateur so here i ask you for your opinion,advice and experience.
So,i make 5 designs for 350l box,tuning frequency from 20 to 30Hz,and port size rectangular shape,width as baffle board and hight as much as i can to get leinght around 40-45cm so i have at least 10cm from back panet to port tunel.
Here i use guidelines from Loudspeaker Design Cookbook,7th edition by Vance Dickason.He said that 2 most important rules with ports are: Area of port must be at least 1/9 of speaker area for minimum nonlineariti in response,but if you want very good port linearity,then port area must be at least 1/4 of speaker area or more.
So here i go with minimum 1/4 surface area ore more.
Second rule he said is minimum distance from back panel to begining of port tunel must be 3",or 76,2mm for metric system,so here i go with minimum 10 cm.
So this 2 rules are fulfill.
Next important thing is that i will use this woofer from 50Hz down.
And now the pictures.
RED - 20Hz tuning
GREEN - 23 Hz tuning
MAGENTA - 25 Hz tuning
BLUE -28 Hz tuning
ORANGE - 30 Hz tuning
So,as i plan to use it from 20 to 50 Hz only,all this design looks good to me.What i dont understand is how will this afect sound quality,and can i go realy that low whit this speaker.
Lost of sensibility is not problem,becuose its for indoor use and it have more then enough power even with this droop in response.
To me best looks 20Hz tuning,in that enclosure i have only 6dB droop from 50 to 20 Hz.
But,this is where my knowlege stops,it looks nice on screen,it have sense to me,but as i said,im a beginer so i dont understand what will hapen in real world and in sound quality.
First idea was to make a horn speker,Wbin,and after big help of some guys here,and discussing diferent types of enclosure,i come to conclusion that maybe is best way to go with ported enclosure.
First i didnt know how to use any software for designing enclosurer but i take time and now i masterd hornresp and winisd 🙂
So after calculating so many diferent designs,conclussion is,if i want to go loooow,and stay in marriage,ported enclosure is the best way. 🙂
I understand that speaker what i have is not the best speaker for what i want to get,but i will try and see what i can get out of him.
So,now the questions.
I make compromise to go max with 400l box,outside dimension,inside 350l.
I make few designs wich look good to my understanding but,im amateur so here i ask you for your opinion,advice and experience.
So,i make 5 designs for 350l box,tuning frequency from 20 to 30Hz,and port size rectangular shape,width as baffle board and hight as much as i can to get leinght around 40-45cm so i have at least 10cm from back panet to port tunel.
Here i use guidelines from Loudspeaker Design Cookbook,7th edition by Vance Dickason.He said that 2 most important rules with ports are: Area of port must be at least 1/9 of speaker area for minimum nonlineariti in response,but if you want very good port linearity,then port area must be at least 1/4 of speaker area or more.
So here i go with minimum 1/4 surface area ore more.
Second rule he said is minimum distance from back panel to begining of port tunel must be 3",or 76,2mm for metric system,so here i go with minimum 10 cm.
So this 2 rules are fulfill.
Next important thing is that i will use this woofer from 50Hz down.
And now the pictures.
RED - 20Hz tuning
GREEN - 23 Hz tuning
MAGENTA - 25 Hz tuning
BLUE -28 Hz tuning
ORANGE - 30 Hz tuning
So,as i plan to use it from 20 to 50 Hz only,all this design looks good to me.What i dont understand is how will this afect sound quality,and can i go realy that low whit this speaker.
Lost of sensibility is not problem,becuose its for indoor use and it have more then enough power even with this droop in response.
To me best looks 20Hz tuning,in that enclosure i have only 6dB droop from 50 to 20 Hz.
But,this is where my knowlege stops,it looks nice on screen,it have sense to me,but as i said,im a beginer so i dont understand what will hapen in real world and in sound quality.
Also,advice what i get from one old speker bulder is to go with sealed enclosure,or with QBE quasi-butterworth or Chebyshev design to get cleanest sound and quick attacking bass with fast response.
But,for this speaker,what i get in WINISD dosnt look good to me.
I will put pictures of these enclosure just for comparison.
screaming blue - 0,577 sealed enclosure
black - quasi-butterworth
yelow - chebyshev
So,what is your opinion,what is the best way to go whit this speaker? I need it for music,movies are not interesting for me,but as some music have deep 20Hz bass,i will like to heare it if is posible,but not on accout of losing sound quality,i dont like mudy bomy boxy bass sound.
So,what do you recommendation?
But,for this speaker,what i get in WINISD dosnt look good to me.
I will put pictures of these enclosure just for comparison.
screaming blue - 0,577 sealed enclosure
black - quasi-butterworth
yelow - chebyshev
So,what is your opinion,what is the best way to go whit this speaker? I need it for music,movies are not interesting for me,but as some music have deep 20Hz bass,i will like to heare it if is posible,but not on accout of losing sound quality,i dont like mudy bomy boxy bass sound.
So,what do you recommendation?
Hi,
If you want to make this into a hifi speaker, none of these graphs show you much of what is crucial other than your excursion and air velocity being appropriately controlled. The rest will change with the room. What's crucial in hifi is actually settling the speaker when the signal stops so that it has rapid settling so that you hear the natural decay of the recording and not the slower decay of a huge mass driver not settling as fast as the recording says to. You would want to see the decay graph and waterfall graph of the speaker to know what's going on there. With a driver this big I think I would go for a sealed design with a lower Q value than typical and EQ to boost down to 20~25hz and drop the 40~50hz range a little to flatten it out, so an EQ/DSP would be needed to do this and work within the xmax limits of the driver. Alternatively you could also do an open baffle sub with a long wing/short wing but it will take trial and error to get the lengths right (model with cardboard first maybe). I don't think I would do ported for hifi with such a big mass driver in a massive enclosure, it's not going to settle quickly, so it will just have a slower bass sound, no hifi. Good for movies, but not hifi.
What hifi are you listening to that gets down to 20hz often enough to warrant such a large sub? Pipe organs?
Very best,
If you want to make this into a hifi speaker, none of these graphs show you much of what is crucial other than your excursion and air velocity being appropriately controlled. The rest will change with the room. What's crucial in hifi is actually settling the speaker when the signal stops so that it has rapid settling so that you hear the natural decay of the recording and not the slower decay of a huge mass driver not settling as fast as the recording says to. You would want to see the decay graph and waterfall graph of the speaker to know what's going on there. With a driver this big I think I would go for a sealed design with a lower Q value than typical and EQ to boost down to 20~25hz and drop the 40~50hz range a little to flatten it out, so an EQ/DSP would be needed to do this and work within the xmax limits of the driver. Alternatively you could also do an open baffle sub with a long wing/short wing but it will take trial and error to get the lengths right (model with cardboard first maybe). I don't think I would do ported for hifi with such a big mass driver in a massive enclosure, it's not going to settle quickly, so it will just have a slower bass sound, no hifi. Good for movies, but not hifi.
What hifi are you listening to that gets down to 20hz often enough to warrant such a large sub? Pipe organs?
Very best,
For best sound quality use a sealed box. To get it to have a balanced LF you need to figure out what sort of room gain you have and then design the system to mirror that. Room gain or pressurization gain will happen below 40Hz or so (higher in smaller rooms). For a well-sealed room you might employ a Q=0.5 to Q=0.6 response and then adjust the corner frequency of the response to match the room. With a sealed box system it is relatively straightforward to use a Linkwitz Transform to do this, since it allows you to independently set Fc and Q of the CB subwoofer.
Once you have figured all of that out you can decide how much bass you need, which will depend on the total max displacement (Sd*Xmax) of all the drivers in use in all subwoofers in the room and available amplifier power. Using more than one sub and optimizing their placement in the room will help to even out room mode resonances.
Once you have figured all of that out you can decide how much bass you need, which will depend on the total max displacement (Sd*Xmax) of all the drivers in use in all subwoofers in the room and available amplifier power. Using more than one sub and optimizing their placement in the room will help to even out room mode resonances.
Thank you MalVeauX!
All have a sense to me and i like what you say.CharlieLaub said same,and i like the sound of sealed box.Im not fan of ported boxes,so im happy that things go on closed box design. If i can not have horn,closed box will be good replacment.How big you think box sould be so i can boost it and flatten to get best of it?
I gona put picture from WINISD and sealed examples.
I want a large sub becuose im a bass player,so for me clean deep bass is MUST Be! 🙂
Pipe organs,Pink Floyd,even Beeatels sometimes go low as 20 Hz,modern fusion muzik,etc. so i like to hear how they want to sound they music.
Thank you CharlieLaub!
So sealed it will be.
Here is picture from WINISD .
light blue 0,577
orange 0,707
green 0,8
red 1,0
dark blue 1,2
This are examples of diferent Q.
So you suggest that i go with Q from 0,5 to 0,6,so 0,577 is then the choice?
Its almost 200l box with Fsc58,38.
And im gona use just one woofer.
Room is 33 squere meters and 85 cubic meters.
7 m x 4.75 m x 2.55 m height
well-sealed room? yes,but is conected with stairs and small hallway with glass doors wich are more or less open all the time.
But that space on stairway is also very good sealed.
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Hi,
The box size and net internal volume will depend on what driver you use and how much signal it gets.
If you want effortless deep bass down to 20~25hz, I would look at a 15" or 18" driver at minimum. For sealed, I would actually look at a 18" driver probably and then figure the box volume based on the driver's T&S values. The driver will be limited by its xmax so you likely want a fairly high xmax and plenty of power to be able to EQ it flat down to 20~25hz.
Budget comes into play heavily here.
Very best,
The box size and net internal volume will depend on what driver you use and how much signal it gets.
If you want effortless deep bass down to 20~25hz, I would look at a 15" or 18" driver at minimum. For sealed, I would actually look at a 18" driver probably and then figure the box volume based on the driver's T&S values. The driver will be limited by its xmax so you likely want a fairly high xmax and plenty of power to be able to EQ it flat down to 20~25hz.
Budget comes into play heavily here.
Very best,
I've not actually built mine yet so I've no personal experience but have a look at this.
https://sound-au.com/project48a.htm
It might be an alternative to the transform
Just remember that you only have 4mm of travel tho.
I am currently mucking about with a similar [ but much cheaper] driver and I don't personally consider it a subwoofer at all
https://sound-au.com/project48a.htm
It might be an alternative to the transform
Just remember that you only have 4mm of travel tho.
I am currently mucking about with a similar [ but much cheaper] driver and I don't personally consider it a subwoofer at all
Thanks Moondog55! It look iteresting. I read it,but i need to read it few more times to understand everything. You think its beter to use this than Linkwitz transform?
Yes,i have 18" speaker,Eminence Kappa Pro 18LS-8,so al pictures are calculations whit this speaker.
I've not yet built one; other priorities at the moment but my 18" is a cheap unit with an Fs of only 31Hz it won't give me the deep bass I crave.
I've got 12" and a 15" [ Fs 24 & 21Hz] and a couple of 15" [ Fs 19Hz] that can reach deeper.
What it is; is efficient and loud enough for parties I guess. Kick drum but not really deep organ tones
I've got 12" and a 15" [ Fs 24 & 21Hz] and a couple of 15" [ Fs 19Hz] that can reach deeper.
What it is; is efficient and loud enough for parties I guess. Kick drum but not really deep organ tones
Hm,i dont need it for patys,just for home listening. My is fs 32hz,so also not deep. But maybe i can go deep enough with so big speaker and SPL for home use?
So big sealed box, don't even worry about the model, the room will change that, and you will EQ the result flat. Nothing more really needed other than to measure the room to avoid bad nulls.
Very best,
Sir,
in times of Internet and eBay, you are not married to a speaker chassis. Sell it and get a decent driver. The usual advice in the 15-18" region for ultra deep bass is Dayton. Available hardly anywhere. With a sub woofer of this caliber, you have to think of the amp, too. The more you force a driver to do things he opposes, the more powa you need. Also, do not start without a DSP. In the end, woofer, amp, DSP and room are a system that has to match.
The cost of a well build cabinet is much higher than changing the driver. Don't start with parts that simply do not want to do the job.
in times of Internet and eBay, you are not married to a speaker chassis. Sell it and get a decent driver. The usual advice in the 15-18" region for ultra deep bass is Dayton. Available hardly anywhere. With a sub woofer of this caliber, you have to think of the amp, too. The more you force a driver to do things he opposes, the more powa you need. Also, do not start without a DSP. In the end, woofer, amp, DSP and room are a system that has to match.
The cost of a well build cabinet is much higher than changing the driver. Don't start with parts that simply do not want to do the job.