Sal's Dynamic series 4T and 4CC

[aqus]

I have chosen to build the 4T and 4CC speakers.
If interested you can follow the progress here:
http://www.htguide.com/forum/showthread.php4?t=32582

[Clearwave]

Well, I'm definitely interested! You might be better off asking some of the more specific questions here just in case I don't make it over to htguide when you need me to. Just thinking it's easier for me to monitor builds in one place. Either way, just let me know if you need anything.

[aqus]

Hey Jed I posted this in the HTguide forum but since you say you read here more often I will re-post here since I would like to close up my boxes.

Does the back part of the mid chamber have to be lined with foam. Just noticed if I seal up the box I won't be able to get to the section behind the mids and tweeters. Or should I wait to get the foam lining before closing it up?
Jed I noticed from your pictures you added foam only after it was all closed up and driver holes removed, so I guess you left the part behind the mids to bare MDF, unless you have very long and flexible arms

[Clearwave]

If you can get the area behind the midrange enclosure lined with Sonic Barrier, that is fine. Mine has Acousta Stuff filling that area and Sonic Barrier on the back wall.

[aqus]

So I guess you put the sonic barrier before closing it or else how do you get it in there? And the acoustica stuff will it hold in place without falling through the hole? especially on the 4 T.
Also on the 4CC your first measurement on the left for the Dayton driver says 4-5/8, but doesn't seem to start from the edge. your arrow head is lined up in the middle of the MDF. Is this right or should the 4-5/8 start from the outside edge. Sorry for the stupid questions but I know these drivers fit tight therefore I am sure every little bit counts.

[Clearwave]

If you are worried about the acousta stuff falling out... you can put a screen or metal mesh stapled into position on the brace to keep it in place. Mine, I just stuffed it up there. I meant I lined the back wall of the woofer chamber. The upper part is just acousta stuff. The mids (4t) are 4.5" away from the center of the tweeter. If you offset the tweeter 3/4" to the right, then the mids are offset from center 3/4" from the left. I'll post back about the 4cc.

Jed

[Clearwave]

The 4 5/8" measurement is correct. I'll fix the alignment of that little arrow.

Jed

[aqus]

Thanks actually I calculated from the center and subtracted the measurements and does come out to 4 5/8 till the edge. Should have done that before.
Thanks for shipping out the rest of the parts. Now lets see who's gets here first, yours or PE.
I will close up my boxes and just put acoustica stuff(or Polyfill in my case) in the chambers behind the mids in the 4T and 4CC.

[Clearwave]

You're very welcome. I also sent you some higher resolution drawings and the crossover layout for wiring everything up.

[aqus]

For the baffle did you cut out the openings then use a rabbet bit, or did you do a first cut of the required depth with a straight bit then cut the rest out. What is the width of the rabbet?
Are woofer.mids and tweeter the same size in width? They seem the same in the build pictures.

[Clearwave]

The baffle is comprised of 2 layers. The inner layer was glued down. Then I used a straight bit to cut the holes about the same size as the diameter of the drivers to allow breathing around the cones. The outer layer can then be glued down, taking note of the driver offsets. You can then rabbet out the flanges, and use a straight bit to cut the holes. The midrange hole in the other layer is 4". A bit more than what PE recommends for the driver. The woofer hole on the outer layer is what PE recommends, as is the tweeter.

[aqus]

Here is a picture of my CC measurements, I checked it many times and don't see how my two extreme drivers are about 1'' in. While Jed seems to cut over the side panel.
Probably doesn't matter since it is only the rough opening.

[ripcard]

The centre is a full inch wider than the towers. The RS180s fit with room to spare in the CC. When you do that same drawing on the towers you will see that the opening will intrude on the sides. This is where you must be carefull when routing and stop before the bit cuts into the sides. Draw some dark pencil lines so they will be visible when the dust is flying and you are lookin through the router base and safety glasses. Cut the pieces out with the jigsaw staying clear of the sides then flush trim them with the router.

[aqus]

Thanks for the reply I know the center is 1 inch wider. I was looking at the two extremities. the woofer lines on the left and right fall inside the side panel, while jed's picture he goes over it a little. the right arrow is where Jed's line ends up...As long as everything fits I guess it doesn't matter...

BTW, ripacard where in Ontario are you? I will be in Ottawa for work next week.
Damn that means I won't be able to advance on my build.
Hopefully this weekend I will get my cutouts done and install the laminate which I will pick up today.

[ripcard]

aqus,

Ooops, sorry, I thought you were refering to the sides. I haven't started my CC yet and I'll probably go the 2 CC modified route anyway so I can't confirm your measurements. I've been playing with Sketchup to see what my proposed centre will look like though. Can't seem to export any file format that I can upload on the board with the freeware version though. Still looking for a decent 2D cad program that isn't too expensive and difficult to learn.

Burritts Rapids is 40 minutes south west of Ottawa along the Rideau River. Unfortunately, a friend and I will be off Tuesday for a 4 or 5 day snowmobile trip. If you can swing out Monday though, you are welcome to drop in and listen to my 2 Ts and chat about speaker building.

Take care, Rick.