ND65-4 Vented build

[bpmoose]

After much advice and info from this thread: http://techtalk.parts-express.com/sh...e-Pico-Monitor
I finally finalized a design and started the project. I settled on a 0.05 cuf enclosure with a .75" x 5.75" port venting out the bottom.

EDIT/NOTE: Box dimensions are 4.5"w X 5.5"d X 8"h. This includes the 1/2" open space on the bottom, so actual speaker enclosure dimensions are 4.5"w X 5.5"d X 7.5"h. I used 1/2" wood, which yields an internal volume of 0.059 cuf. The port is around 0.002 cuf, so actually the enclosure is closer to 0.057 cuf. I estimated .05 after taking the port, speaker, wood to support the removable back, and eventual wiring and binding posts into consideration, but I don't really think those components would take up .007 cuf of space.








not really sure how pvc will work, but I couldn't find a 0.75" port anywhere

[VegaMan]

Re: ND65-4 Vented build

is port tuning below fs of the driver?
any reason you didnt also leave a slot in the front/sides for the vent?
is that poplar?
do you like franks?
do you like beans?
do you like franks and beans?

you can likely ignore the last 3

[Chris Roemer]

Re: ND65-4 Vented build

If I may:

1) Why do you ask THIS? Are you familiar with WinISD from www.linearteam.org ?
2) He wants a tall box, and wants to port w/out resorting to an elbow. His vent ends at the (upper) box bottom. The other 3 sides are just "legs" to lift the port hole off the ground.
3) I don't know the answer to this, and I'm ignoring the last 3.

[VegaMan]

Re: ND65-4 Vented build

If I may:

1) Why do you ask THIS? Are you familiar with WinISD from www.linearteam.org ?
2) He wants a tall box, and wants to port w/out resorting to an elbow. His vent ends at the (upper) box bottom. The other 3 sides are just "legs" to lift the port hole off the ground.
3) I don't know the answer to this, and I'm ignoring the last 3.

1)yes im familiar with winisd. i ask "this" in regards to the whole project. (phase)
2)tall boxes are cool, no elbows on ports are cool, vents staying a minimum of a diameter away from walls are cool, is there an effective tuning change, by porting downwards in a semi enclosed space? in my personal experiences there is (if only slightly) which is why i asked.

you were right to ignore the last 3. me asking questions about a build is about me being curious about the real world experience of someone else. in my experience tuning below the fs of a driver causes a phase shift (on paper), which may or may not be counteracted by moving the port, which is specifically why i asked the question.

[Chris Roemer]

Re: ND65-4 Vented build

A 3/4" port tube only has an area of about 1/2 sq.in. For this one to have its Fb altered, I think the distance the "feet" lift the bottom off the port end would have to be something like 1/8" or less. It LOOKs like he's lifting it maybe 1/2" to 3/4".

Why be concerned about phase when there's no XO involved?

[bpmoose]

Re: ND65-4 Vented build

Please keep in mind this is my very first design, and I am very green when it comes to speaker building...green like the poplar these speakers are made of!

ba-dum-bum

moving on....
I was looking for a small footprint, so went for taller speakers. I tuned it as best I could with winisd, and designed the enclosure off of the port length. I wanted a standard box look, so made front and sides extend a half inch past where the port vents, leaving it open in the back. all purely for aesthetics.

The poplar is a little ugly when raw, but I tested some pieces with stain and found a combination I like.

[the kid]

Re: ND65-4 Vented build

I think it will turn out great! Be neat to make a mini sub of the same poplar cab style.

[joeybutts]

Re: ND65-4 Vented build

For my own ignorance, would it have mattered acoustically if you would have closed the back and opened the front for the port mouth?

[Chris Roemer]

Re: ND65-4 Vented build

n o

[VegaMan]

Re: ND65-4 Vented build

A 3/4" port tube only has an area of about 1/2 sq.in. For this one to have its Fb altered, I think the distance the "feet" lift the bottom off the port end would have to be something like 1/8" or less. It LOOKs like he's lifting it maybe 1/2" to 3/4".

Why be concerned about phase when there's no XO involved?

-port
again this was all questioned regarding someone else's real world experience.
-phase
for nulls. again, on paper x happens, im curious what others find in their projects.

perhaps the "tone" of my original post made it appear i was being mocking or something, i wasn't. the silliness was for the sake of silliness.



"green like the poplar these speakers are made of!"
LOL! i think it's a neat little project and would be interested in your staining process if you'd like to share

[bpmoose]

Re: ND65-4 Vented build

i think it's a neat little project and would be interested in your staining process if you'd like to share

Let me do one more test and I'll share the results. Just want to make sure it works the way I'm hoping! Poplar can be difficult to stain, from what I've read, so I want to be sure it looks ok before sharing what could be a terrible process.

[VegaMan]

Re: ND65-4 Vented build

Let me do one more test and I'll share the results. Just want to make sure it works the way I'm hoping! Poplar can be difficult to stain, from what I've read, so I want to be sure it looks ok before sharing what could be a terrible process.

it takes stain just fine, it's whether or not the green comes through. 'tis why i'm interested.

[WilZirkle]

Re: ND65-4 Vented build

I like beans and franks

[bpmoose]

Re: ND65-4 Vented build

Rounded edges and sanded.

I want to stain the wood, but was looking for a clean, green, low (no) odor stain. I've read about people having trouble getting stains to look right on poplar (it being somewhat green) but have heard good things about dyeing the wood first. I came up with the following solution after researching other DIY stains online.

I stained the raw wood using red wine. One coat and let it dry.



I then painted on a solution of 1 pint apple cider vinegar and one torn up piece of #000 steel wool. After a week, I took out the remaining hung of steel wool and was left with this:


I painted this over the wine. Something about the tannins in the wine and the vinegar solution create a brown dye...it actually changes color in front of you. I plan to finish it with tung oil, which should help bring out the color a little more.

[gleite311]

Re: ND65-4 Vented build

Very clever and creative idea using wine as a stain/dye. I hope you saved some to enjoy a glass before using it all on the cabinets! Looking forward to seeing how these turn out after the tung oil finish