2/3 Way - 'Reference' build

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I want to build a nice (two way) bookshelf for sometime. But the threads mention in post 1# kept me from building a two way because I find the use of an full range driver (and the Dayton Woofer) very interesting. So I am following this thread and maybe I learn something from it.

I already have one question... you put the Dayton in a 25 litres sealed box. Is this the optimum size for it? (I don't have simulation software).

Good luck with your build!

R.

Thank you!

The ~25liters came from X's success with that relative volume in his version.

WinISD suggests ~23.1 as ideal for sealed.
 

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So, I've had a tiny bit of time to make a little progress.

I put together a crossover, to give one channel a listen and to serve as the foundation for measuring.

My modifications to X's crossover are as follows:

C1/C3 is replaced with one 60uF capacitor. I may experiment with bypassing this with some small value, 'high quality' caps at some point.

C2 is 2.22uF, not much value difference there. I had to parallel a few caps I had here.

L1 is 4mH because that's what was on buyout from PE, I will be ordering some other values to get closer to the 4.08mH or wherever I need to adjust this.

R4, IIRC X mentioned this was the DCR of the inductor he was using. My inductor is 0.44R. I have some 1R Mills MRA12's I can put in series to get a bit more resistance if needed.

I cut a quick test baffle for the FF85wk, that's a bit bigger than the tiny little test baffle I cut at first. I chamfered the face of the baffle some as well.

I only had time to listen for ~10minutes to a few pieces of a couple tracks last night. It sounded pretty great, all things considered. I should have put it on a stand to get it away from the wall, I'm fairly certain there was some reflections causing issues, but it was just a very quick and dirty quick listen.

I'll be measuring it properly soon, likely this weekend.

I need to find a supplier for black MDF/HDF. Would be great to find one near me, or a company that will ship 1/4 or 1/2 sheets.
 

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So I've finally been able to slice off a bit more time and make some progress on this project.

I noticed on the initial measurements that the impulse response for the woofer was upside down. I had the polarity reversed. So I fixed that, then took a few measurements.

I test various set-backs for the hf baffle, the best seemed to be ~1.5" back from the front of the LF baffle.

Here are the spl, impulse and distortion measurements from the recent round of testing.
 

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I'm in the process of making new baffles to test, they will be a bit bigger (wider/taller) for the HF portion and will have the 'set-back' built in.

Hopefully I can get those built sometime soon, and test them out.

I just noticed that I have the wrong value in R2 in the schematic I'm going off of. I put in 2.5ohms, instead of 5ohms. I'll correct that and re-measure this weekend.

At some point I am going to test adding some B&G neo3's to the mix. I'm not quite sure where is a good place (hz) to try to add them in. I need to do a bit more research there.
 

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I was able to make a tiny bit of progress on some test baffles this last weekend.

I'm going to test adding a B&G neo3 on top soon as well, if I can slice off enough time soon I'll do a few rounds of measurements with that setup.
 

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618439d1495908765-2-3-way-reference-build-20170526_0002_impulse.jpg


Hmm... this looks like the tweeter is inverted now as the taller peak is downwards. Also looks like you need to add more time delay by moving the tweeter back more until the woofer triangle lines up with the tweeter spike. I did this by flipping woofer above tweeter and placing setup so tweeter is below ear level so takes longer to reach ear vs woofer.
 
Hi X : )

Looks like midtweeter aren't really a 1st or 2nd order slope, by the book 1st is 20dB down a decade below XO point and for 2nd 12dB down one octave below XO point. If one driver in design needs polarity reversed for some reason as for 2nd order its probably best being tweeter in that if speaker shall cooperate at low frq with other speakers be it other HT speakers or sub woofer its right to have woofer push forward on positive impulse.
 
Hmm... this looks like the tweeter is inverted now as the taller peak is downwards. Also looks like you need to add more time delay by moving the tweeter back more until the woofer triangle lines up with the tweeter spike. I did this by flipping woofer above tweeter and placing setup so tweeter is below ear level so takes longer to reach ear vs woofer.

Hell, I didn't even notice that. Thank you for the catch!

I'll re-run those measurements with the tweeter polarity flipped, and I'll measure with a bit more set-back as well.
 
Decent amount of progress made here and there over the last few weeks. I've made a bunch of prototype baffles to test out. Some two way, some three.

A bit more sanding and finish work and the first round of baffles will be ready to pop on, measure and listen to.
 
I was able to cut all the panels for the LF boxes as well, and some braces for them. I did a quick dry fit and they look pretty tight so I should be able to start gluing them up soon.

I've got some CLD material to put on some of the panels before I glue them together. I think I can add the felt after the box is glued together.

That's the plan for now at least.
 
more pics
 

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Looks very nice. Are you adding a super tweeter - hence third hole?

Thanks!

I am going to test adding a B&G neo3. I made some baffles with the cutout for the neo3, and some without so I can measure and listen to both and figure out what's best.

Gluing CLD (noico sound deadening material) to the panel interiors this evening. Once that's done I'll start assembling the boxes.

Definitely getting excited to measure them with the tweeter, will test using miniDSP 4x10hd as well as passive (cap in series).
 
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