893 Frankenstein Tower

Discussion in 'General Topics' started by scary, May 14, 2017.

  1. I wanted a 893 ported towers to go with my sealed 893 center, but wanted the tweeter to be at ear level. In order to get the cabinet dimensions I needed, I cut off the top woofer and re-attached below the other one, then added an extension to give me a total of 38". Actually worked well. Cabinet will be 16" deep, giving me about 70 liters net. The box will be tuned for about 38Hz. Grill covers will be part of the package.
    I'll post my progress as I go, but it's going to slow, because I have MS, and work very slowly. I take a lot of breaks.
     

    Attached Files:

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  2. Looking forward to the build.
     
  3. subscribed.

    Are you going to reinforce the junctions by adding a backing or doubling the entire baffle? Or are you going to leave it as is?
     
  4. I'm not planning to do anything because the joints seem really strong, but it would be easy to glue a reinforcement to the inside. I built the grill covers today - pictures to follow. Damn, those things are a lot of work!
     
  5. Looks great and looks exactly like what I plan on doing. What did you use for the extension pieces? From what I read, the MDF that Erich uses for the baffle is a different thickness than the stuff we get from Home Depot and Lowes.
     
  6. I ended up using MDF from Lowes, which is only about .008 thinner. If you lay the parts face down while clamping them up, they come out flush on the outside. In any case, they are within sanding range..
     
  7. Ok, I have all the pieces cut out. (and produced about a cubic foot of MDF dust). Just have to smooth the holes in all the braces. Then it's time to glue up some cabinets. Sheesh, this is getting to be a lot of work! No matter - I needed a project..
    I dry fit a cabinet, and these beasts are BIG! The Heat Lock veneer glue showed up yesterday, and I still have to choose a veneer - probably cherry.
     
  8. Pictures... just saying... :rolleyes:
     
  9. I hate to admit it, but I can't get the file on my new computer where I can find it and add it to my post. Pretty lame, I know. I'll figure it out in time to send some pics of the assembled cabs. Much more to look at, anyway. Got the bit between my teeth now.
     
  10. Got one cabinet glued up. I didn't have enough clamps (or energy) to do both, but here's one. Notice the braces line up with the joint lines on the baffle. Should be solid as a brick. For the next cabinet, I need more clamps....Trip to Lowes?
     

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  11. Do you have a Harbor Freight by you? Clamps are very cheap, but work well.
     
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  12. Both boxes built. Was tempted to follow your advice, Luis, but just made smarter use of the clamps I have. Today I start on the crossovers and wiring harnesses.

    Two questions: How close can I mount the crossover to the magnetic field of the woofers without affecting the crossover performance?

    When using a port length calculator, it specifies length for specific tuning, but I don't know if that is measured from the
    point where the tube begins to flare at the cabinet end, or at the actual end of the tube. (mouth) Parts Express #480 260
     
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  13. I'm not sure when you will start to notice issues, but I originally had the crossover on the side wall of my center channel; however, I eventually moved it to the back wall as smaller boards became available from an AVS member... I think he's a member here as well @ja00 . I never had an issue, but it was too close in my eyes... my OCD kicked in so I moved it. See below:

    [​IMG]

    [​IMG]

    When I built my L&R cabinets, I made a modification to the center brace on the rear wall that allowed me to install the crossover on the back wall.

    [​IMG]

    Here's the size difference between the two boards:

    [​IMG]

    I'm not 100% sure on how to measure the port, but you might be able to find more info here:

    http://www.avsforum.com/forum/155-diy-speakers-subs/2503962-oak-veneered-diysg-893-build.html

    http://www.avsforum.com/forum/401-d...o-1099-development-thread-7.html#post40174098

    I was going to copy @ccssid build as he built a set of ported towers, so maybe he can chime in with more details.

     
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  14. Thanks for the info Luis.

    I built the crossover for my center channel from scratch. It worked alright, but was, a hassle. This time, I bought a pair of PCBs from Jomar, just like you. What a slick deal that was - fast, compact, and easy. Thank you Jomar! I'm going to put them against the back wall, behind the tweet/mid section. I'm going to use standoffs, attach to an isolated base, and mount them with industrial grade Velcro.
    I reinforced the bottom panel with plywood, so I can use wood screws to attach plinths after the rest of the work is done.
     

    Attached Files:

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  15. Yea, those are nice boards for sure. I used 1/2 or 3/4, forgot the size, standoffs and screwed them onto the back wall as show above.
     
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  16. There should be no issues mounting the boards even behind the CD, that's where I have mine mounted using 1/2" standoffs. The cutout for the CD is huge and that allowed me to use screws to secure the boards to standoffs that are glued/screwed to the cabinet. If you are using velcro you can mount it anywhere inside the cabinet.However if your mounting standoffs are too high and you are concerned about it being too close to the magnet you can mount it behind the mids, The board will fit in that compartment as well, I think :). Glad you are like the boards BTW.
     
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  17. Thanks ja. I'll do about the same thing. I just finished testing the XOs and all the drivers, connectors, etc. Everything, good, so as soon as I can mount the boards, line & stuff the cabs, glue the baffles, etc, I can play with the veneer. Note to self: Buy some veneer..

    Testing components:
     

    Attached Files:

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  18. Ok, boxes and electronics done, one all sanded and pretty'd up for veneer. The other close behind. IMG_1543.JPG IMG_1544.JPG
     
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  19. Looks great! I can't wait to see the finished product. I just finished up my other speaker project, can't wait to start on these.
     
  20. Thanks, I'm pretty happy with the way everything is going together. More pics to come as soon as I finish with the veneer. It's taking a long time, but it's fun work.
    I'm curious about the Denhams, you built. Tell me how they sound? Another question for you is 'where are you using all these speakers? :confused:
     
  21. The Denhams are breaking in now. I am happy with them so far. I built them in a MLTL format, so the bass is great. They sound clear, articulate, and precise. I find them very revealing of the recording quality. Great recordings sound great. Otherwise, you will definitely know.

    I am working my way through replacing all my speakers with DIY speakers. The Denhams are going in the family room, for background music and occasional events. I will be building the 893 towers and center, along with four Volt-6s to replace all the speakers in my dedicated theater room.

    Here are a couple pictures of the Denham towers.
     

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  22. Nice! Is that a laminate you finished them with?
     
  23. #23 Thucker, May 29, 2017
    Last edited: May 30, 2017
    Yes, I used a black laminate that has grains in it. I'd love to do a veneer finish, but wood working time is limited for me. The laminate went on quickly and looks good.
     
  24. They don't just look good; they look very very good. :)

    I considered using a laminate on my 893s, as well, but couldn't sell it to my wife. I went with a mahogany veneer instead. One thing I liked about veneer was that I could avoid contact cement. (and the fumes that go with it) I tried using HeatLock glue. Just coat veneer and substrate, let dry, then iron it on. Works like a charm. People have been using plain old wood glue this way for years, but the HeatLock works better.
    When I get a finish on the speakers, I'll post some pictures and listening impressions.
     
  25. Thank you for the kind words. I am sure your mahogany veneer will turn out great. I've always had a soft spot for Walnut and Mahogany veneer. One of these I'll actually attempt to do a veneer finish.
     

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