Vintage 10" Sub build

[unclejunebug]

Yes, sorry.
A more common Fc for a sub is 80Hz, but I'm typically more like 50 or even 40Hz (8" mains).

No worries, just making sure I understood what you were suggesting.

I'd probably go for the smaller box, and stuff it a bit until I got the response that I wanted. My current HT subwoofer is a 10" driver in a 2.5 cu.ft. box btw...

I think I've resolved to go with the smaller box but now I'm contemplating the box tuning. I figure I haven't built the thing yet so if I can build the tuning into the design of the box/port I'd prefer to do that. I originally wanted to use this 4" precision port because I ordered it and had it on hand. I also considered using a slot port and now I'm mulling over going back to that.

Typically I have seen slot ports designed to be the same width as some internal box dimension. Is there any issue with using a slot with different dimensions than the box? For example, if a box width is 16" is there any problem with having the slot port width be say, 12"? Understanding that the side walls of the slot would have be built out.

[Chris Roemer]

Pretty sure your orig. (3cf?) box running the 4"PP full length would work really well.
No problem with a non-full-width slot. (I've even seen half-width slots (approx.) that "turn" in more than 1 dimension. (i.e. across half the bottom, then back across the other side, THEN turn up for the next layer, etc.)

[Brian Steele]

Both slot / shelf vents and Precision vents should work fine. It's much easier to trim a Precision vent though, if you want to adjust the tuning (which sometimes is required as those box design programs don't take into consideration some factors that might affect the Fb, like proximity of the vent to a nearby wall).

[unclejunebug]

If I went with the slot port I would make it down-firing. I would have it going up one sidewall and then turn and run for a short length along the top. I would have to change the bracing a bit but that wouldn't be too bad.

[unclejunebug]

Ok, so I have a few questions now that I think will determine whether I go with the 4" PP or a slot port...

1. Is there truth to what I've read that the end of the port inside the enclosure should be at least one port diameter away from any inside enclosure surface?
2. How much stuffing would you expect to need in order to lower the tuning from 26Hz to 22Hz?
3. Can the stuffing be loose inside the enclosure or should it be used as lining on the walls? (I was planning to line the walls with acoustic foam)

EDIT: Just found this on Brian Steele 's diysubwoofers.org "Common Questions" page...

2.03 - Where should I place the port(s)?
If your system calls for the use of ports, these can be placed on any side of the enclosure, once the intended location meets the following requirements:

1. The exit of the port should be at least one port diameter away from any external surface.
2. The entrance of the port should be at least one port diameter away from any internal surface, including the driver.

[unclejunebug]

I decided to move ahead with the slot port. If I can design the tuning into the build I'd prefer to do that rather than design the enclosure for a higher tuning and then expect to try and adjust it to where I want it to be. My hope is that I'll have less fine tuning to do this route. Here's what I've come up with....

The slot is down-firing and exhausts out the bottom left side of the enclosure. The port runs up the side wall and then makes a small turn at the top and continues on for a few inches. The port length is 23" which gives me a 20.75Hz tune in a 3 cu^ft enclosure. I added an amp box inside the cabinet to reduce some internal volume.

[anunnaki]

It looks like you have a solid plan at this point.

[unclejunebug]

It looks like you have a solid plan at this point.

I believe I do, though I have stalled a bit as I may need to rethink how to construct the corners. I was planning to laminate some MDF strips together and then use a 2" round-over bit. However, a bit that large is hard to find and rather expensive, the one I have come across is about $170 and I'm not sure it's worth it for just this project.

I'm currently mulling over constructing them with a translam approach but that's going to require me to radius the corner of about 107 2.5"x2.5" pieces of MDF. Not sure how I feel about that haha.

[Chris Roemer]

Some have done large edge radii using "quarter-round" molding.

[Jakes_dad]

This:

[unclejunebug]

I came across that MDF L moulding while searching around. It seems like a good solution except for that pesky shipping charge! Shipping for a single 8' section is about $100 on the site I found. More than double the cost of the moulding itself :(

It's also manufactured to accept 3/4" plywood which I believe is slightly smaller than 3/4" MDF, though I could be wrong about that.

[unclejunebug]

This:
MDF CABINET CORNERS
https://www.tapeease.com

I'm still stalled here but I've come to the conclusion that this "L" corner is my best option. Has anyone ever ordered from this particular site? Originally I was hoping for a pretty large round-over and they have a 3" radius option available. The shipping is also reasonable if they can ship the 8' molding cut into fourths which is what I'd be doing anyways.

[unclejunebug]

Well, I decided to give them a shot and ordered a 3" radius L corner. Their ordering process is a bit of a hassle but they do seem more geared towards cabinet shops rather than someone like me who only needs a single 8' piece of molding. I also ordered the walnut veneer and a few other supplies from veneersupplies. I have the sub and amp so once all the building supplies arrive I can get started!

[unclejunebug]

I'm still in a holding pattern here due to materials. Looks like the product I ordered drop ships from the manufacturer which is fine and fairly common. I received a shipment about 12 das ago and the product looks good. Unfortunately they shipped me someone else's order. I ordered one 8' piece of the L moulding cut into fourths which made shipping very reasonable. What I received was the three 8' foot lengths of the same moulding cut into thirds along with an invoice not intended for me.

I notified the company I ordered from about the shipping problem and they said what would likely happen is that there would be a pickup issued for what I received and my order would have to be shipped out again from the manufacturer. Fine, not a huge deal as I'm not a cabinet shop trying to hit a deadline. I've had a bit of back and forth waiting to hear what was going to happen and today, without any notification, I received another shipment from the manufacturer. Wouldn't you know it, they shipped me the same three 8' lengths cut into thirds.

[unclejunebug]

I requested to keep all the material I've been shipped so far rather than deal with the manufacturer a third time. I got the all clear so I now have a crap load of this moulding but at least I can get started