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Finalist speakers, Tower version. Advice needed concerning TL vs Ported

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  • Paperweight
    replied
    Also a question for Jim Holtz if he is around. Meniscus sent a printed instruction sheet that is copy pasted from the Finalist speakers. It includes the bit about plugging the mid tunnel and the recess on the back panel for that. I believe I have seen you say somewhere that was not an option for the Travelers design. How should the PVC tunnel be mounted between and inside the support braces (caulking or weather stripping for air seal?) and what is the proper material and way of stuffing the mid tunnel to stop standing waves? Thanks!

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  • Paperweight
    replied
    This took a little while to draw up. The scanner cut off the bottom measurement of 15 1/2" for the total width including the outer front baffle. I haven't put this much effort into a pencil drawing since 1994 in drafting class. I wasn't very good at it but I hope this is passable and readable.

    Cut List:

    Inner front baffle and Back panel: 43 1/4" X 9 1/2" 3/4" thick, 2 per speaker
    Outer front baffle: 44 3/4" X 11" ** 1/2" thick **, 1 per speaker
    Side Panels: 44 3/4" X 15" 3/4" thick, 2 per speaker
    Top and Bottom panel: 9 1/2" X 15" 3/4" thick, 2 per speaker

    PVC support panels: 9 1/2" X 7 1/2" 3/4" thick, 2 per speaker
    Inner Solid panel for top of woofer section: 13 1/2" X 9 1/2" 3/4" thick, 1 per speaker
    ML-TL main center panel: 24 7/8" X 9 1/2" 3/4" thick, 1 per speaker
    Window Braces: 9 1/2" X 6 3/8" 3/4" thick, 4 per speaker

    I believe this is correct but I'm not 100% sure. Any corrections would be HIGHLY appreciated before any poor baltic birch plywood is further wasted.

    For some weird reason, my cabinet builder made the mid tunnel supports 7 inches instead of 7 1/2" which is strange since he regularly builds Cambell Holtz speaker cabinets. I need to get him a PDF copy of the instructions if I can get Meniscus to answer an email.

    This whole thing is turning into a bad comedy of errors. I was mad at first but now I'm at the point of laughing about it all.
    Last edited by Paperweight; 04-18-2021, 11:45 PM.

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  • djg
    commented on 's reply
    I had some old guys at a big box store cut a 4x8 sheet into parts for a dollhouse long ago. They screwed it up. They got nasty with me when I pointed out their error. Be careful, it's only wood.

  • Paperweight
    replied
    Using the 3/4" thick inner front baffle with holes for the speakers for this explanation, the mid center is 8 1/4" from the top with the top panel in place. Without the 3/4" thick top panel, it is 7 1/2" from the top edge of the front panel to the mid center. The parts that hold the mid in place are 7 1/2". Cut that in half you have 3 3/4". Add that to the mid center line mark for 11 1/4" and the solid panel goes under that adding 3/4" for 12" total down the front panel without the top panel in place. Paul K's diagram measures from the bottom of that solid divider panel to above the bottom panel for 31 1/4". That is the TL center panel that is 24 7/8" plus the 6 3/8" to the bottom of the panel that seals the top of the woofer section. So the panel(s) have to be 43 1/4" for it to all fit. Add the top and bottom 3/4" panels for another 1 1/2" inches to get the total height of 44 3/4".

    I think I figured this up right. So now it was off by an inch. It probably doesn't matter but it would bug me to no end. As mentioned, it was already messed up to the point of the TL being somewhat correct and glued with yellow PVA wood glue in place but the woofer enclosure top panel was going to interfere with the mid tunnel by that inch the cabinet was off by. What was I supposed to do? I'm not a woodworker and I stupidly assumed the cabinet guy knew what he was doing. This is extremely frustrating.
    Last edited by Paperweight; 04-05-2021, 09:11 AM.

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  • dld
    replied
    Originally posted by Paperweight View Post

    No way, I don't do good enough. I'm too hard core type A for that to pass muster. It would mess up the volume of the ML-TL. I had previosly had everything glued in place correctly for the ML-TL before I discovered the correct placement of the solid panel was going to push the mid tunnel mounts way off center. Knocked it all back apart causing the baltic birch face to tearout.

    Now I'm at square one and have three 4 X 8 sheets of 3/4" BB and one 5 X 5 sheet of 1/2" BB. I have a compact router and plunge base along with a Jasper circle jig for compact routers due to arrive. If you want something done right, do it yourself. This will be interesting.
    oh kay

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  • buggers
    replied
    3/4 of an inch will make no discernable difference in the sound, but by all means redo the box...

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  • Paperweight
    replied
    Originally posted by dld View Post
    I could be wrong, but if only 3/4” off it should be ok.


    No way, I don't do good enough. I'm too hard core type A for that to pass muster. It would mess up the volume of the ML-TL. I had previosly had everything glued in place correctly for the ML-TL before I discovered the correct placement of the solid panel was going to push the mid tunnel mounts way off center. Knocked it all back apart causing the baltic birch face to tearout.

    Now I'm at square one and have three 4 X 8 sheets of 3/4" BB and one 5 X 5 sheet of 1/2" BB. I have a compact router and plunge base along with a Jasper circle jig for compact routers due to arrive. If you want something done right, do it yourself. This will be interesting.

    Edit: Upon further inspection, almost every dimention of this cabinet is completely off. He seems to have followed a plan that was nothing like the original Finalists/Travelers. He made something wider and shorter than you would expect and put pocket screws so the front and side panels are assembled opposite of the original plan. I paid extra for biscuits to help with assembly. Even they were off by a 1/16" all around.
    Last edited by Paperweight; 04-18-2021, 11:42 PM.

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  • dld
    replied
    I could be wrong, but if only 3/4” off it should be ok.

    Originally posted by Paperweight View Post
    I had the cabinets made by someone in flatpack form. Correct me if I'm wrong but shouldn't the 4 main 3/4" thick panels be 43" in length? They were cut to 42 1/4". I believe the cabinet guy forgot to factor in the solid divider panel. This is going to be ugly.

    Leave a comment:


  • Paul K.
    replied
    I don't happen to have a drawing for the complete Finalists cabinet and don't know what its height dimension was. All I did was model an ML-TL for the woofer section. You can see on the drawing earlier in this thread for that section that all of the dimensions I show are INTERNAL dimensions because that's what the modeling software uses. If someone wanted to use 1"-thick cabinet walls they could as long as the internal dimensions I show were correct.
    Paul

    Originally posted by Paperweight View Post
    I had the cabinets made by someone in flatpack form. Correct me if I'm wrong but shouldn't the 4 main 3/4" thick panels be 43" in length? They were cut to 42 1/4". I believe the cabinet guy forgot to factor in the solid divider panel. This is going to be ugly.

    Leave a comment:


  • Paperweight
    replied
    I had the cabinets made by someone in flatpack form. Correct me if I'm wrong but shouldn't the 4 main 3/4" thick panels be 43" in length? They were cut to 42 1/4". I believe the cabinet guy forgot to factor in the solid divider panel. This is going to be ugly.

    Leave a comment:


  • Paul K.
    replied
    As long as you build the TL section as shown in my drawing with the correct dimensions and locations of woofer and port you'll be okay.
    Paul

    Originally posted by Paperweight View Post
    Well, I did that right then. PE had 3" x 4" unflared ports for 98 cents and I did buy 2. I was almost tempted to buy the Precision Port kits. Good thing I asked. Thanks!

    I'm tempted to break the cabinet into two parts with the tweeter and mid in the top cab and the woofer in the bottom cab. I guess I could move the top panel that encloses the woofer section down 3/4" and extend the bottom panel down by that much to make up the difference. I could use 1/2" ply in the bottom of the tweeter and mid cabinet with about a 1/4" gap I could use for a mounting scheme and to decouple the vibrations of the woofer cabinet from the top.

    It certainly would make working on each half so much easier. Also, even in Baltic birch, this thing is going to be heavy.

    Leave a comment:


  • Paperweight
    replied
    Well, I did that right then. PE had 3" x 4 1/2" unflared ports for $2.92 and I did buy 2. I was almost tempted to buy the Precision Port kits. Good thing I asked. Thanks!

    I'm tempted to break the cabinet into two parts with the tweeter and mid in the top cab and the woofer in the bottom cab. I guess I could move the top panel that encloses the woofer section down 3/4" and extend the bottom panel down by that much to make up the difference. I could use 1/2" ply in the bottom of the tweeter and mid cabinet with about a 1/4" gap I could use for a mounting scheme and to decouple the vibrations of the woofer cabinet from the top.

    It certainly would make working on each half so much easier. Also, even in Baltic birch, this thing is going to be heavy. I'm also assembling it with hide glue this time. It is one of the few glues I know I can get back apart without tearing out the facewood on BB.

    Any suggestions or comments welcome. There's lots of stuff I'm unfamiliar with when it comes to do's and don'ts.
    Last edited by Paperweight; 04-12-2021, 10:17 PM.

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  • Paul K.
    replied
    In Post #8 I included a scale, side-view drawing of the cabinet with dimensions. While the dimensions for the locations of the braces weren't shown, you should be able to determine those locations from the drawing, but their locations aren't particularly critical either. The port is not flared on either end because Martin King's software I use for TL designing is correct only for ports without flares.
    Paul
    Paul

    Originally posted by Paperweight View Post
    I'm working on a set of floor standing Travelers with Paul K.'s ML-TL for the woofer. Two questions.

    Do you have any rough dimensions for the spacing of the braces inside the ML-TL?

    Anything special about the port? Flared on one or both ends?

    If I can ever get one of these together without every small goof driving me to smash it to pieces insane, it would be the first speaker I ever put together without step by step instructions.

    Leave a comment:


  • Paperweight
    replied
    I'm working on a set of floor standing Travelers with Paul K.'s ML-TL for the woofer. Two questions.

    Do you have any rough dimensions for the spacing of the braces inside the ML-TL?

    Anything special about the port? Flared on one or both ends?

    If I can ever get one of these together without every small goof driving me to smash it to pieces insane, it would be the first speaker I ever put together without step by step instructions.

    Leave a comment:


  • Paul K.
    replied
    That same question was asked in a previous post in this thread and I responded that I was pretty sure the internal width was 9.5". For a revised port you could simply use two of the same length and diameter as the single port in the single-woofer design, assuming the line's volume was truly doubled. A volume increase other than x2 would require new new modeling to determine a new port(s) dimensions.
    Paul

    Originally posted by ontariomaximus View Post
    Hi Paul, what is the width of the RS225 TL above? And if I scale it up for 2 x RS225, what happens to the port?. I might go a little less than 2.0X. Maybe 1.7X
    thanks

    Leave a comment:

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