This is a side view of what the enclosure would look like.
A port of 3" diameter-to be safe-adn a length of 10" would tune this to 30 Hz.
The divider in the middle would make this an enclosure of 50" long, 6" wide by 6.5" deep.
For simplicity's sake, the vent would have to be at the back.
The divider could be made by gluing two pieces of 3" wide mdf which you inserted through the woofer cutout and glued in place. This should prevent the necessity of having to pull apart the entire enclosure to put in the divider.
A port of 3" diameter-to be safe-adn a length of 10" would tune this to 30 Hz.
The divider in the middle would make this an enclosure of 50" long, 6" wide by 6.5" deep.
For simplicity's sake, the vent would have to be at the back.
The divider could be made by gluing two pieces of 3" wide mdf which you inserted through the woofer cutout and glued in place. This should prevent the necessity of having to pull apart the entire enclosure to put in the divider.
Attachments
Well, here is one possiblilty.
I would have to work it out better tomorrow, using a different section of the software of the same freeware suite by Martin King.
But it should work.
There are other possiblities besides this.
The brown is the port, 3" dia by 10" long.
The space between dividers, side view, is 6 inches. Or 5.5 inches, depending on thickness of building material.
I would have to work it out better tomorrow, using a different section of the software of the same freeware suite by Martin King.
But it should work.
There are other possiblities besides this.
The brown is the port, 3" dia by 10" long.
The space between dividers, side view, is 6 inches. Or 5.5 inches, depending on thickness of building material.
Attachments
Back tomorrow with a comment. Little late tonight.
By the way, the divider you made at the top of the box-is that to enclose the midrange, or merely to make a separate compartment for the mid/tweet?
In other words, is it worth modeling with the upper divider removed just to see how it comes out?
By the way, the divider you made at the top of the box-is that to enclose the midrange, or merely to make a separate compartment for the mid/tweet?
In other words, is it worth modeling with the upper divider removed just to see how it comes out?
Okay, here we go.
the multiple dividers idea shown above did not simulate out too nice-the length of the quarter wave Transmission Line should be at least an octave or so above the tuning frrquency, and it was too long that way.
Here is a better way.
Simply run a divider down the middle, stopping 3.75" from your upper divider. the pipe, shown in blue, is 3" diameter. Run the pipe through the divider. If you use an elbow, you might have to cut the hole large enough to fit the elbow throug-I'll leave that part up to you.
Horizontal of the section of pipe is 8.5" from the inside of the enclosure wall, the vertical section is 4". We are measuring from the center of the pipe. Throw in the fact that the pipe extends out through the 3/4" MDF of the enclosure, and we have a pipe 13.25" long.
You can lay the horizontal section of the pipe on the floor of the enclosure if you like, or raise it an inch or two above it. No difference either way. The vertical section should be approximately down the middle of the enclosure, which should be about 5.25 wide.
An inch or so of pipe length is not going to throw the tuning off to any major extent. So relax.
That centerline of the Tangband at 9" is also an approximation, an inch or two either way isn't going to throw anything off.
Those two little V blocks I put in there at the bottom of the upper divider were just to smooth the response, I don't really know if they're necessary. But there they are.
0.3 lb/cubic foot Dacron stuffing. The enclosure is exactly one cubic foot.
Let me know how it comes out.
the multiple dividers idea shown above did not simulate out too nice-the length of the quarter wave Transmission Line should be at least an octave or so above the tuning frrquency, and it was too long that way.
Here is a better way.
Simply run a divider down the middle, stopping 3.75" from your upper divider. the pipe, shown in blue, is 3" diameter. Run the pipe through the divider. If you use an elbow, you might have to cut the hole large enough to fit the elbow throug-I'll leave that part up to you.
Horizontal of the section of pipe is 8.5" from the inside of the enclosure wall, the vertical section is 4". We are measuring from the center of the pipe. Throw in the fact that the pipe extends out through the 3/4" MDF of the enclosure, and we have a pipe 13.25" long.
You can lay the horizontal section of the pipe on the floor of the enclosure if you like, or raise it an inch or two above it. No difference either way. The vertical section should be approximately down the middle of the enclosure, which should be about 5.25 wide.
An inch or so of pipe length is not going to throw the tuning off to any major extent. So relax.
That centerline of the Tangband at 9" is also an approximation, an inch or two either way isn't going to throw anything off.
Those two little V blocks I put in there at the bottom of the upper divider were just to smooth the response, I don't really know if they're necessary. But there they are.
0.3 lb/cubic foot Dacron stuffing. The enclosure is exactly one cubic foot.
Let me know how it comes out.
Attachments
Oops. Change of dimension.
After thinking about it, I realized the length of the divider should be changed. the space between the divider and the top divider should be 5 3/8", not 3.75".
In other words, the vertical divider should be 19 5/8" long.
This change keeps the cross section area of the Line constant throughout-5 3/8" deep by 6" wide.
Here is the new diagram. I requested that the moderators change the original diagram in post #36 to this new one, as well. To avoid confusion.
After thinking about it, I realized the length of the divider should be changed. the space between the divider and the top divider should be 5 3/8", not 3.75".
In other words, the vertical divider should be 19 5/8" long.
This change keeps the cross section area of the Line constant throughout-5 3/8" deep by 6" wide.
Here is the new diagram. I requested that the moderators change the original diagram in post #36 to this new one, as well. To avoid confusion.
Attachments
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.