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Build of gr-research X-LS Encore

D

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Am finishing the bracing and prepping to wire the crossovers. Was surprised to find the supplied wire is solid core with a hard vinyl jacket. Maybe this is why there is shrink wrap supplied too? Looked at the crossover his posting and looks as though he only uses shrink wrap to insulate anywhere he makes an external wiring connection to the crossover. Given exposed point to point wiring everywhere, not clear what benefit is being achieved. :confused: Since the solid core will pull harder on the board connections as drivers are wired and mounted, is more beneficial to tie down those connections in my opinion.
Throw that solid wire where it belongs..........in the shit can.
I want to know why that internal wire is not braided, high capacitance stuff to prevent RFI ingress. :)

Dave.
 

amirm

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Am finishing the bracing and prepping to wire the crossovers. Was surprised to find the supplied wire is solid core with a hard vinyl jacket.
I can't believe people use solid core wires in speakers with all the vibration going on there.
 
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Rick Sykora

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In preparation for installing drivers, mounted drivers to establish screw hole positions and found that the woofer overlaps the tweeter partly. Normally would not be a problem but was a little conservative with tweeter recess and fitment was unacceptable. I have a few past remedies for this, but the new jig provided a cleaner one. I mounted a brace across the cabinet inside and, carefully re-established the center for the tweeter cutout. The Jasper jig came with 2 centering pins. To handle to additional depth, had to use the longer one. This worked out pretty well with a little touchup trimming needed with a razor knife. I also use this opportunity to mount a flushing bit on my other router and clean up the joints.

The flush bit works well when the top piece overlaps the adjacent pieces. In my case, this was a mixed bag as the front baffle had top and bottom edges the slightly overlapped, but the sides went slightly the other way. In this case, I use a nice sharp 1" chisel to even up the joint. Will need to repeat (and sand) after I attach the back baffle, so will show better then. Here is a pic of the drivers mounted...

76C56EFA-7E2E-4B95-B872-B34446A47547.jpeg
 
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Rick Sykora

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Now to do some wiring. First need to mount the crossovers...

D1318522-D6B9-4448-86CD-1D50D0DE40B9.jpeg


Am going to use the solid wire although it is tough to strip. I did not find much use for the shrink tubing electrically, but did use it to damp the driver wiring where it might hit cabinet internals. Here is the final wiring...

0A644C48-1CAE-48CA-B521-0E2DC8EB98B6.jpeg


Note I also added some cable ties where the driver wires might pull on the connections to the crossovers. Do not normally do with stranded wire, but want to avoid breaking anything as I add/remove drivers.
 
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KaiserSoze

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Rick Sykora

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Just wondering about that liquid nails glue. Does it seem strong? Does it shrink? Does it stay pliable? What's the cure time?

Define strong? Pretty sure wood glue would be "stronger". No, it does not shrink and yes it stays somewhat pliable. If had to guess, it is being used to try to produce a Constrained Damping Layer effect. Total cure time is 24 hours but was able to glue the top braces about 30 minutes after the fronts. :)
 
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Rick Sykora

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Was a busy day and had to run out for some terminal connectors. Attached them and glued the back baffle on. Looking forward to doing an acceptance test in the morning, and if all goes well, some listening too! :)

The moment of truth draws near...
 
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Rick Sykora

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Okay, if you are building, hope you had your Torx bits ready as all the screw heads use! You will need both #15 and #20. While I prefer them, may catch the beginner off guard. Given the lack of instructions, I feel this is more of a kit for a more experienced hobbyist. This is mainly due to the lack of instructions on crossover layout and the cabinet damping question as well. While cabinet needs a bit more sanding, it is functional. So here it is just before the first tests...

FE22B5FC-3938-4122-A3F0-E7A01035C5EA.jpeg
 
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Rick Sykora

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Here is the moment of truth. The first impedance measurement of this build. As discussed earlier in the thread, the base kit did not include any damping (or readily specify either). So, you may or may not be surprised by this...

gr x-ls encore base Z.jpg

So, while it does fairly closely match the one posted one the GR web page for this speaker, the box tuning is slightly higher. Of course the reference one does not have any of the ugly resonances between 500-800 Hz either! So, naturally, the next question is what is the cause and how best to remedy.
 
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Does the second speaker have an identical impedance sweep? If so, I'd say those are characteristic blips are associated with a spider/basket resonance, or something similar.

Dave.
 
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Rick Sykora

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Does the second speaker have an identical impedance sweep? If so, I'd say those are characteristic blips are associated with a spider/basket resonance, or something similar.

Dave.

Amir only needs one, so the second is still parts for now. I could swap in the other woofer, but none of my subsequent measurements have indicated that it might be the root cause. I am compiling them and will share later today. I am listening now and will need to set up my frequency response fixture before I can say that my build is a valid representation of the design. :cool:
 
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Rick Sykora

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Could be back wave reflection upsetting the driver.

Not a bad guess based on some of my later measurements, but...

May be at half a wave length or so. The cabinet depth is 10.5", so might account for the blip around 1200 Hz (13,400/10.5 = 1276 Hz).
 

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He sells the kit without it so there is nothing unfair about it. If we add all of his options it may double the price and then someone claims we made it too expensive for no reason.

Excuse me if I sound ignorant and certainly haven't read the whole thread, but isn't it silly to build a speaker as a big empty box with NO FILL and not expect it to have undamped resonances. Polyfill even from using pillow stuffing is very cheap and while you have concerns about about dust, I would point out that every commercially available ported speaker uses some form of polyfill.

P.S. It's one of the few times I agree with Maty.
 
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Yeah, even if not employing the recommended/expensive NoRez, that doesn't mean 'no' filling should be used. A light lining/filling is standard issue on almost all vented box speakers.

Dave.
 

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Maybe doing what you suggested on page two, complete both speakers and apply filling to one of them, would be for the best. I'm guessing that the discussion of the actual review would probably focus on this point no matter what the results were.

Edit: Lest I forget, many thanks for helping the community by building these!
 
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amirm

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Excuse me if I sound ignorant and certainly haven't read the whole thread, but isn't it silly to build a speaker as a big empty box with NO FILL and not expect it to have undamped resonances. Polyfill even from using pillow stuffing is very cheap and while you have concerns about about dust, I would point out that every commercially available ported speaker uses some form of polyfill.

P.S. It's one of the few times I agree with Maty.
We are following their instructions. If there is no mention of using fill then that is that.
 
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