No, I think that's too small with high resonant frequency, bell curve type and high Qtc. A bigger one is better. Look at the Qtc instead that you need to start. To help you, look at the Qtc color picture from this French website. (1) First you chose Qtc, (2) second the calculations gives you the ideal internal volume for your loudspeaker.
Enceinte accoustique close
If you want you can use the software bellow, for that matter.
WinISD - LinearTeam
UniBox by Kristian Ougaard UniBox - Unified Box Model for Loudspeaker Design
Enceinte accoustique close
If you want you can use the software bellow, for that matter.
WinISD - LinearTeam
UniBox by Kristian Ougaard UniBox - Unified Box Model for Loudspeaker Design
You can make the sub enclosure of the bass reflex type having either shorter ports and a less diameter, like the ones you posted the link, but in this case it's good you know that some high speed air shuffle will make some noise at higher SPL output. No problem at comfortable listening levels. You can design them to the side or back out from direct listening position.
Shorter ports such as this SVS PB12 subwoofer??
I imagine a properly tuned 15" woofer would eat most 12" subs for breakfest.
Perhaps 2-3 ports?SVS PB12-PLUS 12 2300W Ported Subwoofer (Black Oak) - $1,849.00 ...
Clearly its a compact sub, only 25 long , 19" high
I imagine a properly tuned 15" woofer would eat most 12" subs for breakfest.
Perhaps 2-3 ports?SVS PB12-PLUS 12 2300W Ported Subwoofer (Black Oak) - $1,849.00 ...
Clearly its a compact sub, only 25 long , 19" high
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No, no. Think like this. Suppose you are going with a ported system (BR). Then if you are using the ports you linked on post #13, shorter ports will give you a smaller diameter, with 3x ports large like those in your post #23 you will have several meters in length for such a FB in this case (post #2).
Let's say for the same alignment (VB = 130.5 L/FB = 16.9 Hz) that you buy a Precision Port 3" Flared Port Tube Kit
you need to use a 11" to 1ft in lenght. That's why you should manufacture your own tube/port with máx. length permited by max speaker dimension, so that diameter can be maximum (1 or two ports) for the same tunning frequency.
Let's say for the same alignment (VB = 130.5 L/FB = 16.9 Hz) that you buy a Precision Port 3" Flared Port Tube Kit
you need to use a 11" to 1ft in lenght. That's why you should manufacture your own tube/port with máx. length permited by max speaker dimension, so that diameter can be maximum (1 or two ports) for the same tunning frequency.
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Let's make another alignment case.
STEREO INTEGRITY HT 15, VB = 130.5 L, FB = 20.0 Hz
Using this port Precision Port 4" Flared Port Tube Kit 268-352 you will need about 14" to 15" because it's 4" diameter (constraints) and the tunning frequency is 20Hz.
STEREO INTEGRITY HT 15, VB = 130.5 L, FB = 20.0 Hz
Using this port Precision Port 4" Flared Port Tube Kit 268-352 you will need about 14" to 15" because it's 4" diameter (constraints) and the tunning frequency is 20Hz.
Attachments
why does Stereo integrity suggest tuning freq 22hz?
I am still rather confused to tuning ported subs
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I don't know, but certainly it's a bad alignment.
5ft³ = 141.58L
As they say Ported = 5 ft^3 tuned to 22 Hz For 5ft³ you will need a 20Hz tunning. Again that's relative, after you are in the process you might change tunning as you like. But if you do not simulate before you build I am sure you will build or attract a... disaster. Also very important, the alignments for car are completely different from alignments in room or audiophile because of many variables. A room gain can be between 0.5-2dB/octave@200Hz and in a car being between 8 and 11dB, just as a crude idea.
There's nothing confusing after you start using the simulation software I linked twice for you on post #6 and post #21. They have variables for port dimensions
+1 I AGREEI don't know, but certainly it's a bad alignment.
5ft³ = 141.58L
As they say Ported = 5 ft^3 tuned to 22 Hz For 5ft³ you will need a 20Hz tunning. Again that's relative, after you are in the process you might change tunning as you like. But if you do not simulate before you build I am sure you will build or attract a... disaster. Also very important, the alignments for car are completely different from alignments in room or audiophile because of many variables. A room gain can be between 0.5-2dB/octave@200Hz and in a car being between 8 and 11dB, just as a crude idea.
There's nothing confusing after you start using the simulation software I linked twice for you on post #6 and post #21. They have variables for port dimensions
Confused me also & didn't make since I swore those spec's didn't make any since.
Tuning above FS didn't make since to me... cuz Sub falls off below FS.
so 18-16 hertz wud be best for tuning....
Is ported better in a small room? Or sealed 12.5' x 13' room
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I don't know, I can not predict that. You can go perhaps to the next chapter on room acoustics and calculators. You can read, test and simulate I guess.
By the way when you mention your room you forget the most important measurement the height of the room. Also important are the type of construction and sound absorption materials like windows and carpets in percentage of the area/side. Example: a sound studio is different from a bathroom.
Room Acoustics
Acoustic Calculation Tools
Port Calculation
By the way when you mention your room you forget the most important measurement the height of the room. Also important are the type of construction and sound absorption materials like windows and carpets in percentage of the area/side. Example: a sound studio is different from a bathroom.
Room Acoustics
Acoustic Calculation Tools
Port Calculation
Attachments
How well do 3" inch flared ports do?I can tune two 3" inchers lower for deeper bass if needed.I don't know, I can not predict that. You can go perhaps to the next chapter on room acoustics and calculators. You can read, test and simulate I guess.
By the way when you mention your room you forget the most important measurement the height of the room. Also important are the type of construction and sound absorption materials like windows and carpets in percentage of the area/side. Example: a sound studio is different from a bathroom.
Room Acoustics
Acoustic Calculation Tools
Port Calculation
Would I lose SPL or they would have more port noise?
1. two 3" ports 17" long tuned to 18hz
2. two 3" ports 15" long tuned to 19hz
Sub Driver should arrive eventualy
Amp Ill order when I decide port size
Do you have the subwoofer already (Stereo Integrity HT 15")? Does it look good?!
Now ports size (internal diameter/length) they are related to the tunning frequency. That's a constraint of the bass reflex type of enclosure. Very low tunning frequency gives a gigantic almost impossible port length (several feet). To work in the limits of the practical, one dimension of the enclosure would be the max length of the port, that's what I have in mind. I need to know the 3 dimensions (of the enclosure) available or the one for the port you choose to be located (H, L or D internal of the box).
Now (example) for a Ported = 5ft³ tuned to 22 Hz
(5ft³ = 141.58L)
(note: the problem with tunning FB = 16.9 Hz is a port so many feet long that it doesn't fit inside the subwoofer enclosure and it's quality is bad.)
Max tunning frequency FB = 20 Hz.
So this is very critical if you do or don't have the space inside the box for this port. (When you don't have the electronics to modify the output curves of a speaker) The best bet, in this case, is to make say an ideal box with ideal (or more practical in this case) tunning with higher Fb.
It doesn't matter if you use a box from 3.5ft³ (99L) to 6ft³ (170L) it takes a max. tunning of 20Hz for a close to ideal alignment and with this driver.
1. Let's say 5ft³ (141.58L) tunned to FB = 16.9 Hz (ideal),
port 4", length ~20", air speed very high @70.4 m/s (max. 25.5 m/s).
(very difficult to work with the low frequency tunning)
2. 5ft³ tunned to FB = 20 Hz
port 4", length ~14", air speed very high @95.8 m/s (max. 25.5 m/s).
3. (Now with 2) 2 ports 4":
port 4"(x2), length ~29", air speed high but better @47.9 m/s (max. 25.5 m/s), results in a very long and bad port length.
4. Let's make another test with the port with a rectangular port:
port 1"x20" (HxW), length 15", air speed very high at high volumes 95.2 m/s@115.0 dB but ok at low volumes 13.7 m/s@98.2 dB.
So, I would use this alignment with this port if testing assure me it's ok.
5. Let's make yet another test with another rectangular port an different alignment:
Ported = 5ft³ tuned to 18 Hz
1"x20" (HxW) rect. port, length 19" (L), air speed high at high volumes 78.5 m/s@115.2 dB, ok at low volumes 15.4 m/s@101.1 dB.
So, after all this is my last simulation for such an alignment and the dimensions of the port system with the Stereo Integrity HT 15" in response to your PM.
How to Choose the Right Saw for the Job
Use wood glue (make sure it's approved for wood not paper glue, contact or another kind).
Now ports size (internal diameter/length) they are related to the tunning frequency. That's a constraint of the bass reflex type of enclosure. Very low tunning frequency gives a gigantic almost impossible port length (several feet). To work in the limits of the practical, one dimension of the enclosure would be the max length of the port, that's what I have in mind. I need to know the 3 dimensions (of the enclosure) available or the one for the port you choose to be located (H, L or D internal of the box).
Now (example) for a Ported = 5ft³ tuned to 22 Hz
(5ft³ = 141.58L)
(note: the problem with tunning FB = 16.9 Hz is a port so many feet long that it doesn't fit inside the subwoofer enclosure and it's quality is bad.)
Max tunning frequency FB = 20 Hz.
So this is very critical if you do or don't have the space inside the box for this port. (When you don't have the electronics to modify the output curves of a speaker) The best bet, in this case, is to make say an ideal box with ideal (or more practical in this case) tunning with higher Fb.
It doesn't matter if you use a box from 3.5ft³ (99L) to 6ft³ (170L) it takes a max. tunning of 20Hz for a close to ideal alignment and with this driver.
1. Let's say 5ft³ (141.58L) tunned to FB = 16.9 Hz (ideal),
port 4", length ~20", air speed very high @70.4 m/s (max. 25.5 m/s).
(very difficult to work with the low frequency tunning)
2. 5ft³ tunned to FB = 20 Hz
port 4", length ~14", air speed very high @95.8 m/s (max. 25.5 m/s).
3. (Now with 2) 2 ports 4":
port 4"(x2), length ~29", air speed high but better @47.9 m/s (max. 25.5 m/s), results in a very long and bad port length.
4. Let's make another test with the port with a rectangular port:
port 1"x20" (HxW), length 15", air speed very high at high volumes 95.2 m/s@115.0 dB but ok at low volumes 13.7 m/s@98.2 dB.
So, I would use this alignment with this port if testing assure me it's ok.
5. Let's make yet another test with another rectangular port an different alignment:
Ported = 5ft³ tuned to 18 Hz
1"x20" (HxW) rect. port, length 19" (L), air speed high at high volumes 78.5 m/s@115.2 dB, ok at low volumes 15.4 m/s@101.1 dB.
So, after all this is my last simulation for such an alignment and the dimensions of the port system with the Stereo Integrity HT 15" in response to your PM.
When you buy you need a jigsaw with wood blades. (Google)
How to Choose the Right Saw for the Job
Make it (more) thick for such a big monster woofer.
Use wood glue (make sure it's approved for wood not paper glue, contact or another kind).
Same content here from OP.
http://www.diyaudio.com/forums/subwoofers/232138-sealed-vs-ported-sub.html#post3420727
http://www.diyaudio.com/forums/subwoofers/232138-sealed-vs-ported-sub.html#post3420727
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