830875, xt25 + wave guide build

[DIYNut42]

Those cabinets turned out great! The whole build looks like it's going to be awesome. I'm going to have to look for some bigger sheets of that veneer some time. I really like that look.

[bkeane1259]

Those cabinets turned out great!

+1

Beautiful job on that veneer....really sweeeeet.

[perfecxionx]

I got a lot of use out of the home made circle guide, so finally the waveguide has been fitted, but i still need to trim it and probably router the rear side where the tweeter will have to meet up with the wave guide. Its not in the photos but I did chamfer the the woofer cut out so its not suffocated too much

[perfecxionx]

yea, im still here working on this. I hope to be able to move on to the xover in the next week. I decided to just use duratex paint for the baffle but as I'm trimming down the waveguide to meet the tweeter at the rim of the bevel around the diaphragm its bothering me that the waveguide is becoming trimmed so much that its ceasing to be a wave guide at all. To fit snuggly around the bevel (rather than just the diaphragm) the hole needs to be about 1.75" in diameter.

I'm also going to have to mill the rear side of the baffle close to a .25" so that the tweeter and waveguide will sandwich the baffle sufficiently. I was planning on just using weather stripping between them all to get a seal, but im unsure if that will be adequate. (?)

[critofur]

Are you gonna take the faceplate off the tweeter so the waveguide edge can go down properly?

[perfecxionx]

Are you gonna take the faceplate off the tweeter so the waveguide edge can go down properly?

It doesnt seem most other people had done that, and im not sure how i would then mount the tweeter. Didnt zaph just press the faceplate against the wg?:





http://www.zaphaudio.com/Waveguidetmm.html

[critofur]

That tweeter's faceplate is flatter...

Maybe I should try to see if it's worth bothering/somehow to mount it. I have the tweeter and some of those waveguides.

I haven't seen closeups of many other people's interface between waveguide + XT25...

[perfecxionx]

That tweeter's faceplate is flatter...

Maybe I should try to see if it's worth bothering/somehow to mount it. I have the tweeter and some of those waveguides.

I haven't seen closeups of many other people's interface between waveguide + XT25...

Removing the plate might be better, but isnt the faceplate also glued down? I tried removing it a while ago and noticed that the entire soft part assembly was being pulled up with the faceplate. So i got scared and gave up on that idea. Is there some trick to safely removing it?

[ryanbouma]

I had the same scare when I tried to remove the faceplate from mine. Would be interested in knowing if it can come off.

I left the faceplate on and did what you're doing. Ya, the waveguide was pretty shallow by the time I milled the throat far enough open. 1.75" sounds about right. Don't worry though, it measured quite well. In fact I later put it in a deepper waveguide made by TN Allen and it worked but wasn't as good. The SB29 did really well in that waveguide so I thought it would be good. But it wasn't. Just ok.

[perfecxionx]

I'm not sure i could mount the guide to that bare tweeter surface without cutting some type of adapter =
(http://www.troelsgravesen.dk/ScanSpeak-waveguides.htm), and doubt i have the tools to cut something quite like that anyways

[perfecxionx]

I've found a few photos of similar builds, and it appears that they were done with the faceplate, its tough to see well though

[perfecxionx]

I had the same scare when I tried to remove the faceplate from mine. Would be interested in knowing if it can come off.

I left the faceplate on and did what you're doing. Ya, the waveguide was pretty shallow by the time I milled the throat far enough open. 1.75" sounds about right. Don't worry though, it measured quite well. In fact I later put it in a deepper waveguide made by TN Allen and it worked but wasn't as good. The SB29 did really well in that waveguide so I thought it would be good. But it wasn't. Just ok.

Any pics or links you can post?

[ryanbouma]

Ah, I didn't do a build thread or anything. I crossed it active. Still have them built but not being used right now. Oh shoot, no I have them built up with the other "lesser" waveguide I mentioned. What did you wanna know? I paired it with the Dayton DS175 and crossed around 1400hz iirc.

[ocdSCHACK]

I built a set of speakers with these drivers and they are still my favorites. They really sound amazing, so you should be more than satisfied with your build once completed. Here's a link to my build thread. http://techtalk.parts-express.com/sh...cdschack+build
Also, there's a link to the screws I used to rear-mount the woofer in one of the posts if you are still considering it. Lastly, that veneer looks awesome...great choice and good job!

[Wolf]

The XT25 used to be easier to remove the faces, but they had issues with impedance diffrences just by rotating the faceplate to resolve them. I'm now guessing they check the results, and glue them in place to avoid any other mishaps or faulty curves.

Later,
Wolf

[critofur]

What I would do (were I not so lazy and busy) would be to grind the portion of the waveguide where it interfaces to the tweeter such that it is thin enough to fit in that area right outside the outer ring (between it and the raised plastic bumps).

I'm not sure it would be better, perhaps the shape engineered into the faceplate is superior and we would be best to try to just get the waveguide to press up flush to right where the faceplate starts to curve down from the front like what you're doing?

Of course, if it measures well, then there's no need to try and "fix" it

Wolf, thanks for that info - I've got one XT25 with a double dip impedance - I was thinking of fiddling with the faceplate or trying to swap two. After reading your post I definately will.

[perfecxionx]

What I would do (were I not so lazy and busy) would be to grind the portion of the waveguide where it interfaces to the tweeter such that it is thin enough to fit in that area right outside the outer ring (between it and the raised plastic bumps).

I'm trying to imagine how I might do that on my router table and nothing seems like it would give me the kind of precision necessary...

I'm not sure it would be better, perhaps the shape engineered into the faceplate is superior and we would be best to try to just get the waveguide to press up flush to right where the faceplate starts to curve down from the front like what you're doing?

That's what i was wondering, I was kind of hoping you guys would have the answer to this. Since the faceplate obviously was not designed for a wave guide, I'm not sure if that little bevel would be good or bad to mate up to the wave guide.

[critofur]

You can always test ideas with modelling clay.