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Was the crossover ever finished or tweaked ? If i remember that thread stated they were close but needed tweeked....Or are you going to do the crossover yourself ?


I like the design but i prefer the MTMWW but thats just me. I will be keeping an eye on this one.

Thank You for posting.

John.
 

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I am watching this closely.


i have have a TV stand for a rear projection the WMTMW layout puts the tweeter right in place when i put it on the tv stand that i built a foot wider than needed for this reason.
 

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Discussion Starter #4
As far as the crossover, I don't think he ever did the tweaking beyond what the htguide thread discusses. I'm doing the WMTMW arrangement for half for looks and half for functionality. My center channel (To Be Built) won't have the height of the tweeter in WWMTM, and figured I'd keep them as close to the same height as I can (for what its worth).


Since my receiver (Yamaha RX-V765) doesn't have the guts to drive sub-4ohm speakers to high levels, I will be driving these with a Stewart PA1000 power amp from the pre-outs on the receiver.


Hopefully, I can keep progress on this moving quickly enough to be interesting.
 

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Discussion Starter #5
Here is the design I have in mind:




Constructed of 3/4 inch mdf. Painted with satin or flat latex interior paint to match the color of my unfinished birch TV stand (pics in one of my older threads). The port is on the bottom of the main enclosure supported off the base by threaded rod encased by PVC pipe (also like my tv stand). The grill is TBD for now. I may like the looks without it.


I was going to go with a solid wood (knot-free pine) enclosure, but after reading lots of other people posing the same question, they were encouraged to use mdf instead to avoid problems with warping, cracking, and humidity.


I have cut most of the larger pieces, and will do some work with the radial arm saw to cut the rest this afternoon.
 

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Discussion Starter #6
Enclosures under way! Made some progress yesterday. These things are going to be bigger and heavier than I thought they'd be.





And I never seem to have enough clamps. Thank goodness for brad nailers. I only use brads where the nail will not be routed or cut later, and there are some things that are much to difficult with clamps alone. Hope to get baffles routed and port tubes installed this afternoon.
 

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Discussion Starter #7
The whole family has been sick for most of a week, but I finally managed to get some progress made. Time for a much needed update.


One thing I learned was that sheet mdf can have a natural bow to it. While I didn't notice when I built my tritrix speakers a while back (likely because they were much smaller), these larger towers showed some considerable bow to them when I was getting ready to clue the front/rear panels on. Had I noticed before I had done some of the construction, I would have had the curves oppose each other so it would end ups straight in the end. But I didn't, and thus they needed to be held straight for gluing. See my method of straightening below: Note, that is a piece of 3/4 in 1x6 oak that I bent against it...




I did use my 18 ga finish nailer to help move the process along here, too. Once everything was dry, I flush-trimmed all edges, cut all the driver holes, and put a 1/2 inch roundover on all sides. Here's where they stand as of now:




I used a 50/50 mix of wood glue and water to help seal the edges. I used this on my sub build and it worked quite well at preventing the paint from soaking into the cut edges. They stand 44 inches tall right now, will be 50 inches tall when done.


I was going to use regular black ABS for the ports, but didn't want to hassle with it and ordered some 3" precision ports as per mpotoka's parts list.


Next steps will be installing the ports, finishing the base-plates, then building the crossovers.
 

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Looks nice!! Thanks for the update.
 

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Those look killer. Working on my Statements which have a similar WMTMW layout.


You have to love that box full of stuff from Parts Express!
 

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Discussion Starter #12
Crossovers assembled (not soldered yet):




The two on the right are for the Woofers, and the two boards on the left are combined Mids/Tweets.


Crossovers are probably my least favorite speaker building item to spend time on. I was going to make them all pretty with the solders and wires all hidden under the boards, but said, "screw it". No one will see these anyways... I hope to solder them up this afternoon.
 

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Discussion Starter #13
Okay, so yesterday I managed to get the crossovers soldered and do a quick speaker polarity check with a AA batt to make sure the speakers were wired correctly.


Now for a noob question. Does it matter how the wires go to the crossover from the amp? Of course I would keep both speakers identical, but does it matter which line the red/black goes to? Here's the crossover pic:




Which line off of the source is red/black, and which side of the speaker is pos/neg? The tritrix build I did before had too much info and videos for me to have gotten this wrong, but this build is a bit more demanding for me.


Brian
 

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In that schematic, positive is up from the source. So all the xovers are parallel from the source. The positive/red goes to the horizontal components in series.
 

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I'm not 100% sure I understand the question, but YES. The negative typically has no components in series and goes straight to the output terminal of the drivers.
 

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Are the woofers wired out of phase with the mid/tweets in that schematic?
 
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