jwc Posted March 23, 2006 Author Share Posted March 23, 2006 Well, I don't see a cutout. Again my concern is the testing of these. I can't glue the pieces together until I know exactly what length to use. The vibrations w/in the cabinet will probably make them fall apart w/o the glue. I'm going out of town this weekend and will be able to resume the cutouts next week. I appreciate the input so far. At this point my goal so far is this. Dual Ports below the driver aligned horizontally and very close to each other. Ports/flare to be at least 4 inches from the bottom of the cabinet. Place driver as close to top of cabinet as possible. I am gonna have to unmount the driver everytime I need to change a port length. Can I get a vote on what length to use for each port to start with. Remember, this is a 6.5 cu ft cabinet and I am using Bob's Pre-1985 K33E-like driver. jc Quote Link to comment Share on other sites More sharing options...
DizRotus Posted March 23, 2006 Share Posted March 23, 2006 Is this what you're looking for? Quote Link to comment Share on other sites More sharing options...
DrWho Posted March 23, 2006 Share Posted March 23, 2006 Again my concern is the testing of these. I can't glue the pieces together until I know exactly what length to use. The vibrations w/in the cabinet will probably make them fall apart w/o the glue. Duct tape? I am gonna have to unmount the driver everytime I need to change a port length. Can I get a vote on what length to use for each port to start with. Remember, this is a 6.5 cu ft cabinet and I am using Bob's Pre-1985 K33E-like driver. What tuning point are you aiming for? I came home for spring break and thus don't have all my numbers, but isn't the cornwall tuned somewhere between 35 and 45 Hz? You definetly want to tune on the low side because it's easier to make the port shorter than it is to make it longer. I believe a 30Hz tuning comes to 8" per port (from mouth to mouth - ignore the correction chart that comes with the ports). I would start there and shave down as necessary. Don't forget to use T-Nuts on the driver so you don't have to worry about stripping the wood: http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=260-778 Quote Link to comment Share on other sites More sharing options...
DrWho Posted March 23, 2006 Share Posted March 23, 2006 Is this what you're looking for? The drawing shows up while editing, but is not visible to me in the edited post. Is the drawing visible to everyone else? The upgraded forum will take practice. Use the attach file button, not the insert image button. Insert image only works for files already uploaded to a server on the internet (right now you are linking to your harddrive). The attach file button can be found on the "options" tab up a bit higher. (you will see "compose" "options" "related" "preview") Quote Link to comment Share on other sites More sharing options...
jwc Posted March 23, 2006 Author Share Posted March 23, 2006 Hmm. Is that image for the 4 inch? Man, I'm not sure why I didn't think of Duct tape. I am predicting a final port length between 4-6 inches. I just want a fairly flat response. Will probably be tuned just under 40Hz. I have always contemplated the T-nuts. Don't have any. I am expecting to only unmount the driver a few times. I will start with #8 screws and the final will have #10. jc Quote Link to comment Share on other sites More sharing options...
jwc Posted March 23, 2006 Author Share Posted March 23, 2006 I don't recall seeing cutout plans with mine either. Jwcullison, I believe these plans on the LS project that I am doing was your Idea. Have you ever ported LS through the to section? or just an Idea? oops. I missed this question. I was involved in some past threads regarding porting the La Scala...It could have been me. If I were port the La Scala and build from ground up, I would use the top section as the ported section and turn the bass bin upside down. The just set a 511 and tweeter on top. Quote Link to comment Share on other sites More sharing options...
Xover Posted March 30, 2006 Share Posted March 30, 2006 Just a thought. Why not cut the baffle board in half ( actually closer to the woofer leaving enough room for a horizonal brace where the two Baffle parts meet. This will allow you to remove the bottom portion to tune the ports. It would also allow you to make extra bottom pieces to try different port placement. It is my experience the port placement is not critical so long as there are no obstructions front or back to cause turbulence and you tune the ports in the box real time ( theoretically one could possibly stick the ports in backwards so they extend out in the room for convenience while tuning). I found that if you place the ports in the bottom corner of the box it works fine but the tuning length is a bit shorter than elsewhere on the baffle. Quote Link to comment Share on other sites More sharing options...
Rotorhead09 Posted March 31, 2006 Share Posted March 31, 2006 Hello JW, That is what I am doing now. I am porting throught top section. I have some pics I tired to post in the modded/upgrade LS thread but could not get them to show. If I can figure it out I will post what I have done. Quote Link to comment Share on other sites More sharing options...
jwc Posted March 31, 2006 Author Share Posted March 31, 2006 Xover, that is a clever idea with the different baffle for the ports. Good idea for a testing box. May consider doing that on another project. Roto. I would like to see the pics if you get a chance. Will you port in front or back? Bt the way, I grew up on Primrose street. This neighborhood had a park on the corner of an intersection. My backyard was a cotton field. My sisters went to Washington Academy. Once I hit Kindergarden, I moved to Starkville. My father used to manage one of the first Honda dealers Called C & W Honda (Cullison and Woods). jc Quote Link to comment Share on other sites More sharing options...
Rotorhead09 Posted April 1, 2006 Share Posted April 1, 2006 JW, I am porting them through the top back. I will try to scale the photos down and repost them on Monday or pm me with your email and I will send them to you that way. Quote Link to comment Share on other sites More sharing options...
Rotorhead09 Posted April 2, 2006 Share Posted April 2, 2006 One more time! Quote Link to comment Share on other sites More sharing options...
Rotorhead09 Posted April 2, 2006 Share Posted April 2, 2006 Here is a pic next to factor one. Quote Link to comment Share on other sites More sharing options...
Rotorhead09 Posted April 2, 2006 Share Posted April 2, 2006 Shot down the top, ports not finished yet. Quote Link to comment Share on other sites More sharing options...
BEC Posted April 2, 2006 Share Posted April 2, 2006 Looking good there. Man, some of that stuff looks familiar. Bob Crites Quote Link to comment Share on other sites More sharing options...
BS Button Posted April 2, 2006 Share Posted April 2, 2006 JC's got some stiff competition with those babies. Looks like a Crites tweeter horn and an Arkansas cedar crossover. Fire 'em up. Quote Link to comment Share on other sites More sharing options...
jwc Posted April 2, 2006 Author Share Posted April 2, 2006 Nice to have stiff competition with a Mississippi boy. I know all about STIFF competition....right Todd. Looks like your cabinets and mine will have a bunch of BEC stuff. jc Quote Link to comment Share on other sites More sharing options...
BEC Posted April 3, 2006 Share Posted April 3, 2006 I really like competition when the competitors all buy their parts from me. Bob Quote Link to comment Share on other sites More sharing options...
Rotorhead09 Posted April 3, 2006 Share Posted April 3, 2006 Hey guys, This is just another project for me. I, for sure am not an expert! I always wanted a set of LS and this is the only way I could justify it. I owe you guys on this forum for all your help. Bruce has gone beyond the call of duty with info. I just hope these things sound as go as they look! Anyone with advice on how much stuffing (insulation) to put in this turkey? Quote Link to comment Share on other sites More sharing options...
DrWho Posted April 3, 2006 Share Posted April 3, 2006 Anyone with advice on how much stuffing (insulation) to put in this turkey? I would only put stuffing at the bottom of the bass bin and then underneathe the top panel. I would not line the vertical sections of the doghouse (it'll affect the behavior of the driver in the port). The only other place I might consider insulation would be along the top of the bottom panel in the top section (the panel the crossover is sitting on). If possible, I would try mounting the crossover to one of the vertical sections in the top-section. I also highly doubt you'll need insulation along these vertical sections due to a point of diminishing returns (the size of the panel is very small relative to the wavelengths, and you won't really be exciting horizontal waves). For a cheap solution you can go to your local fabric store and purchase pillow filling...it's the same poly-fill stuff that audio stores will over charge for. Always start with no stuffing and then add as needed. You should be able to clearly hear any resonations that are occuring. As far as mounting - I usually get by with just not sanding the wood and the stuffing kinda sticks like velcro. If it's not sticking well then you can even try using some velcro, but I usually go with T-Pins. If you go with quilt stuffing, it comes in sheets which makes it very easy to fold and hold its shape. You want the stuffing to be firm, but not hard and definetly not fluffy. And you probably want it about 3" think or so. Anyways, this is just my limited experience of stuffing...I'm sure others will chime in. Quote Link to comment Share on other sites More sharing options...
Rotorhead09 Posted April 3, 2006 Share Posted April 3, 2006 Dr. Who, Let me see if I got this right. Get pillow stuffing and start at the bottom of the bass bin, Then line bottom of ports and top of ports? Do I fill up the dog house part? Quote Link to comment Share on other sites More sharing options...
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