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Discussion Starter #1
Thanks to PartsExpress' free shipping this weekend I just ordered the amp (BASH 300) for my CSS SDX10 build.

Current thoughts are a down-firing ported configuration. ~1.8cu ft tuned to ~25hz. The port will face up and just for fun I will make a plate that can be used to block the port and turn it into a sealed configuration. The cabinet will be designed to fit behind a corner entertainment center.

This is just a placeholder for now. Don't hold your breath on the project start. I have to finish a pair of floorstanders and said corner entertainment center before I can start in earnest.

Thanks again to CSS + the shack for the driver!
 

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Ah, eyekode, I saw your thread and thought I was getting too far behind starting my own SDX10 build. I'm glad you're holding off for a bit as well, so I don't look so bad. ;)

I've also got a BASH 300 to power mine, and I'll get started once I knock off a few other projects that have lingered a bit too long. Can't wait to see yours.
 

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Discussion Starter #5
I am ever so close to starting the build :). I have almost finished my entertainment center. My garage only has room for a few projects at once.
http://photos.ganzhorn.org/album697
The new sub is going to go behind it. Still playing in sketch-up trying to figure out a good way to do the non 90 degree joints. I will post the sketchup models when they are ready. Good luck with your build!
 

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Discussion Starter #7
Got a table mounted router or can you get one? If so, look at a locking miter joint.

http://www.woodshopdemos.com/cmt-lm5.htm
I thought about that but it is a 70$ solution that still requires precision setup. I am thinking of a poor-man's locking miter (see attached image).

A little more explanation: It will be placed in the corner but I will not be doing any 45's. Instead I am going to do 22.5's. Like the shape of home plate :). This leaves me with just two though joints and all the rest 90's. This is also very similar to how I did my entertainment center (link is in previous post).
 

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Discussion Starter #8 (Edited)
So I finally got my entertainment stand in the house and setup. Turns out I have less room than I had hoped behind the stand. So I had to redesign the sub to be much taller.

Final metrics:
Net volume of enclosure: 1.66 ft^3
4" port ~25" long for a tune of ~25Hz.

This is not quite a good as the recommended 1.77 volume but it is already going to be 4 feet tall and the difference in WinISD is very small. I will just add more stuffing.

It will be powered by a Bash 300 plate amp.

See the attached image for the concept. I should be able to start cutting this week.
 

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Discussion Starter #9
I ended up doing a little different design, partially by choice and partially because I did something(s) stoopid :). This project will now be known as the "Corner Loaded Base Snorkel".

I am usually very careful and precise with the engineering side of a project. First I drew up a spread sheet parameterized by the important geometries:
1) the width of the baffle.
2) the depth of the sides perpendicular to the baffel.
3) the height of the enclosure
4) the number of braces
5) the length of the port
6) the radius of the port (both inner and outer)

I plugged in numbers till I found the tuning I wanted, ~25hz with a 4" port (flared at both ends). The front baffle is about 14 inches and the height is 49". Then I drew it in SketchUp and made a cut list.

Then I got busy at work and life. When I finally got back to it I pulled up the spreadsheet and headed to the store. I bought 4" PVC. This was my first mistake. I had modeled ABS which is ~3.8 diameter on the inside. PVC is 4" inside diameter. To make matters worse I had hard-coded the outer diameter in a formula in the spreadsheet... I don't know why. But of course I did not notice this and thus miscalculated the length of port needed and started cutting.

This design was pretty complex to manufacture. I ended up doing 3/8" rabbit's on all edges that join at 90 degrees to increase glue area. The 135 degree joints I used biscuits. I did two dadoed cross braces, one of which serves as the flare for the port inside. The front baffle is 1.5" thick where the driver is mounted.

Here are some pictures gluing on the sides:



Next up is the port. I went back to double check my spreadsheet... and found the hard-coded cell :hissyfit:. This is the point where my project got it's name :). I needed an extra 4.75" of port length. I wasn't about to start over at this point so I decided instead of terminating the port on the top of the sub I now needed to extend the port above the enclosure!

Here are some pictures gluing up the port. The cross-braces are not glued in, I just inserted them in the dadoes so the port attached to the two cross-braces would fit perfectly. The bottom of the PVC was not exactly square so I cut a very slight grove to accept the end of the port and cover the slop. I used gorilla glue for the port-to-cross-brace joint.




Can anyone see my next mistake? See the clamping pressure on the top of the top brace? That pulled the cross brace slightly out of vertical. And therefore it would no-longer fit perfectly in the dadoed back pieces. Oh well, a chisel and more gorilla glue :).

Next up I sealed the inside of the cabinet with Zinsser BIN. This is to keep the inside from absorbing moisture and telegraphing joints to the paint job. I had never used this stuff before but it is really nice. I won't use sanding sealer again.

Some pictures before the final glue-up:


Here you can see the 3/4" round over on the inside port end:


And here you see some plywood I glued to accept the screws for the driver. I don't trust screws in MDF:


And one more for good measure:


I glued it up about 2 weeks ago and have been listening to it since. I plan on going back and building a small extension to hide the snorkel and provide a round over for port on the outside.

I tested it with an SPL meeter and it gets plenty loud down low. I can however hear port noise, but it is not as loud as the front door behind the wall rattling :).

Honestly my initial impression is that I prefer my 4ft^3 ported Mistral. On the CSS when playing 20Hz I hear 40Hz +. I don't remember the second harmonic even being audible on the Mistral. Note that this is not a final conclusion and it is not a fair comparison. The Mistral is mated with much better mains and is a larger driver.

One day when it warms up I will get this beast painted and post more pictures.

Thanks again Shack for the driver!
 

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I like that!!
This is the part I like about DIY you can build almost any shape and size and make it look good:T

Nice woodwork skills there my friend, Looks really good!!!!!:hail:
 

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Discussion Starter #12
Yep... neat idea... would love to see some finished pics in the setup. :yes:
I am not in any rush to paint it. Here is a picture of it in use:


Can you you see it peeking out from behind the TV? It is almost completely obscured. Eventually I want to build a new base for my TV that will totally hide it along with any wires and also elevate the TV ~4" so I can put some DIY bookshelve speakers on the cabinet. So eventually it will be completely hidden, but this is what it looks like today (with the entertainment center pulled out):


By the way building the entertainment center is what took me sooo long to get to this point on the build :)
 

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Discussion Starter #15
eyecode, have you listened any more? Does the sub provide much impact during music?
I have not yet given it a fair listen. I still need to elevate my screen by ~4" to fit some decent speakers on the stand.

I will say it can move a fair amount of air! "Impact" shouldn't be a problem as long as the room isn't huge.
 
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