Budget Aura NS35 + Nuance TM

[XtremeRevolution]

NOTE: The NS35 driver from Madisound.com used in this design is no longer available.

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Built a new speaker based on my own design, for the first time! Granted, I had a lot of help with the crossover (ok, someone designed it for me), but otherwise this is more of my design than anything I've ever done, and I'm happy to report that they sound amazing. Very good value for what I spent on them.

Nuance TW5-2LR Tweeter: $3.75
http://www.parts-express.com/pe/show...number=279-061

Aura NS35-255 Driver: $4.50
https://www.madisound.com/store/prod...oducts_id=8992

Crossovers: $10.64 per

Total for the speaker pair: $37.78

I bought over 10 so I only paid $4.25 each for the drivers. I also added a round push-type terminal for an additional $1.10 per cabinet.


For this design, I decided to use poplar because its light, its cheap, and it will stain very nicely. However, I know its not as dead as MDF so I decided to go crazy with this project. This project involves 20 separate cuts of material per cabinet.

Doubling up each panel with two 1/4" thick panels does a few things. First, it allows the panels to be more dead due to overlapping wood grains, since I would otherwise have parts of the wood on a 1/2" piece that would be more dead than others. Also, the generous and even distribution of wood glue between the panels adds more rigidity. The other thing is that these will look superb with roundovers, as you will be able to see 4 different wood grain panels with the 1/2" roundover bit I'll be using.

Crossovers are from this thread:
http://techtalk.parts-express.com/sh...86#post1723786












Mounting the drivers was a big challenge because there is technically no usable flange width at the N, S, E, W points, so I had to mount them on the much wider ridge below and use some weather stripping to seal them up. I will be trimming the weather stripping so it looks better later.

I got these put together quickly so I could use them during a bonfire we had today so I didn't get to take a whole lot of pictures, but I put a good amount of stuffing inside and they sound great. They definitely got loud enough to have to yell over in our back yard on my Lepai amp, and while the bass isn't too great, its definitely there and its enjoyable for casual listening. Honestly, at this price point, you can't have everything and they are a great value for what they are. Very clear and crisp sound and very wide sound stage.

More pictures to come once I get them rounded over and stained.

[XtremeRevolution]

Almost done! Just need to stain them and get some of my open cell egg-crate foam on the walls that I can reach since they resonate a small amount. Got them stuffed nicely with polyfill, and they sound just as good as they look. Can't wait to hear my mom's voice on the phone when I ship these out to her. She has no idea I'm even making them.

[mikejennens]

Those really look nice. Looking forward to the pics when you get the stain/paint/finish on them? Nice touch with the double layer. I love the whole idea of trying to make good sounding, good looking, affordable speakers. No audio-snobs allowed!
Mike

[XtremeRevolution]

Those really look nice. Looking forward to the pics when you get the stain/paint/finish on them? Nice touch with the double layer. I love the whole idea of trying to make good sounding, good looking, affordable speakers. No audio-snobs allowed!
Mike

Thanks! I'll try to get a stain that makes the wood grain really stand out. I absolutely LOVE the way the double layers look on the roundover. Makes them look genuinely natural. There are a couple gaps where I couldn't tighten the clamps down enough and you can see a thin strip of wood glue, but nobody's perfect and you have to look at them up close to see it on the sides.

The wood gives them a real nice, warm sound. Seriously, I think these sound absolutely amazing for $37 speakers. I'm going to be building some more of these.

[XtremeRevolution]

BTW, I'm having such a damn good time right now.

Cold beer, 80 degrees and windy, smell of "big storm is coming" in the air. Quite relaxing.

[LSV8]

I will try my best to explain my method of sealing pincusion drivers without pictures, lol. If I could find a picture of the back of one, it would be easier!

Take a look at the back of the driver. See how the frame is stamped in "steps" near the mounting flange? The first step is a flat surface that the surround is glued to, just slightly lower than the face. Then there is another step to transition to the basket. (Hope you're following me, I should really just go take a picture!)

What I do is cut my hole to the diameter of the inner step. Just big enough to fit the basket of the driver, but small enough that the first "step" cannot fit into the cutout.

Then, I use a 45* chamfer bit and go around the edge just a bit, not too deep, til I find the exact depth to fit the driver's "stepped" portion. You should be able to cut it just right so that the driver sits in the chamfer without any of it being visible around the smaller areas of the frame.

Once you have your depth perfect, add a thin layer of silicone to the chamfer. Just enough to create a gasket. Let the silicone fully vulcanize before installing the driver, and you will have an air tight reusable seal. (I would however suggest leaving this step out til AFTER you have finished your cabinets, as stains/paints/etc do NOT like sticking to silicone!)

Has worked great for me on all of the TB pincusion frame builds I have done.
(50 some cutouts by my count )

[XtremeRevolution]

Well then, I guess I'll be in the market for a chamfer bit for my router soon. Thanks for that tip, I understood what you meant perfectly. The weather stripping seems to hold up very well for now so I'll leave these be, but for the next ones I build, I'll definitely do it that way. The baffles are permanently glued on, so if I mess it up, I'm going to have to add another layers to the baffle to fix the problem.

Thanks again!

[LSV8]

Well then, I guess I'll be in the market for a chamfer bit for my router soon. Thanks for that tip, I understood what you meant perfectly. The weather stripping seems to hold up very well for now so I'll leave these be, but for the next ones I build, I'll definitely do it that way. The baffles are permanently glued on, so if I mess it up, I'm going to have to add another layers to the baffle to fix the problem.

Thanks again!

No problem.

I think you'll get good use out of a chamfer for the inside of the baffle on those tiny drivers too. 3/4" wood really obstructs the rear of the cone on those little guys.

Give it a try on some scrap first so you can get it just right. And make sure you post pictures for reference since I neglected to!

[XtremeRevolution]

No problem.

I think you'll get good use out of a chamfer for the inside of the baffle on those tiny drivers too. 3/4" wood really obstructs the rear of the cone on those little guys.

Give it a try on some scrap first so you can get it just right. And make sure you post pictures for reference since I neglected to!

Will do. I'm planning on building a few more of these out of 1/2" MDF so I'll get plenty of practice time in.

[XtremeRevolution]

Alright, I've been listening to these quite a lot since I built them and I am very pleased with their sound. I really don't think you can do much better at that price point. My only gripe is the lack of bass without some kind of bass boost intervention. I discovered that the suspension is pretty stiff which might have something to do with it. Otherwise, they're great little speakers and the Lepai amp runs them perfectly.

Now I just need to stain them. I bought the stain yesterday (dark mahogany) and will be finishing them up tonight to send to my mom. Now I just need to get a new Lepai amp to replace mine, and they're out of stock...

[XtremeRevolution]

[XtremeRevolution]

I didn't like how some of the wood didn't absorb the stain as much as other parts, so I did a light sanding and applied another layer of stain. Much more even now.

Polyurethane satin clear coat is going on tomorrow for the final finishing touch.

[patrickm]

I didn't like how some of the wood didn't absorb the stain as much as other parts, so I did a light sanding and applied another layer of stain. Much more even now.

did you use a pre-stain / conditioner? that helps the stain absorb more evenly and deeply. (is that the minwax mahogany? these threads have some examples of how those have come out on pine for me before with the mahogany and a few others -- i just sand, pre-stain, and 20 min later use the first polyshades coat with a foam brush or paint edger. 000 steel wool in between, then coat two).

http://techtalk.parts-express.com/sh...d.php?t=219684
http://techtalk.parts-express.com/sh...d.php?t=217610 (the second pair, about 10 posts down)

it's kind of a pain, but try a test board first... if it's better by a wide enough margin, your best bet is to sand them down and start over.

[XtremeRevolution]

did you use a pre-stain / conditioner? that helps the stain absorb more evenly and deeply. (is that the minwax mahogany? these threads have some examples of how those have come out on pine for me before with the mahogany and a few others -- i just sand, pre-stain, and 20 min later use the first polyshades coat with a foam brush or paint edger. 000 steel wool in between, then coat two).

http://techtalk.parts-express.com/sh...d.php?t=219684
http://techtalk.parts-express.com/sh...d.php?t=217610 (the second pair, about 10 posts down)

it's kind of a pain, but try a test board first... if it's better by a wide enough margin, your best bet is to sand them down and start over.

I did use a pre-stain, and I used the Lowe's brand Dark Mahogany color. I'll check out those speakers. At this point I already have two coats of polyurethane so I'm probably not going to start from scratch, but I'll do some practicing on spare wood pieces.

[Chris Roemer]

I did use a pre-stain, and I used the Lowe's brand Dark Mahogany color. I'll check out those speakers. At this point I already have two coats of polyurethane so I'm probably not going to start from scratch, but I'll do some practicing on spare wood pieces.

I'd check with your XO guy. The last sim he had showed your tweet out of phase with other little driver. Wiring it the other way should boost output in the XO region, meaning the tweeter could get by with even smaller (cheaper) caps & coils, otherwise you should just try his version w/out the coil (cheaper yet).

Chris

[XtremeRevolution]

I'd check with your XO guy. The last sim he had showed your tweet out of phase with other little driver. Wiring it the other way should boost output in the XO region, meaning the tweeter could get by with even smaller (cheaper) caps & coils, otherwise you should just try his version w/out the coil (cheaper yet).

Chris

What XO are you talking about? There are 3 XOs in that thread.

Also, what does it mean when they're out of phase?

Are you suggesting I use this one?

[XtremeRevolution]

I'd check with your XO guy. The last sim he had showed your tweet out of phase with other little driver. Wiring it the other way should boost output in the XO region, meaning the tweeter could get by with even smaller (cheaper) caps & coils, otherwise you should just try his version w/out the coil (cheaper yet).

Chris

Wait, did you mean by "wiring it the other way" that I could just swap the wires on the tweeter to help these get more "in phase?"

I haven't yet started building my second set and I do plan on ordering many more kits to build more of these in about 2 weeks, so I could definitely switch up the driver if I need to.

[Chris Roemer]

Wait, did you mean by "wiring it the other way" that I could just swap the wires on the tweeter to help these get more "in phase?"

I haven't yet started building my second set and I do plan on ordering many more kits to build more of these in about 2 weeks, so I could definitely switch up the driver if I need to.

I gathered that you were using the 2nd order HP (cap & coil). The plots that your designer posted showed the "summation" plot actually BELOW the tweeter plot, meaning that in the XO region, that the tweeter and woofer were fighting each other - "out of phase", the same as hooking 2 stereo speakers up to an amp with the red/black wires switched on one.

Woofers OOP (out of phase) are very noticeable 'cause the bass goes away (the closer the cabs are, the greater the cancellation).

When a tweeter's OOP with a midbass, the response varies "wildly" as you move off the "on axis" line. If your cross point was at 4kHz, for example, stuff below about 2k and above 8k could sound OK, but if you move (your head/ears) around the speaker playing a 4000 Hz tone, you'll hear all kinds of volume changes w/position, including full summation as well as "drop outs".

When 2 drivers are simming "generally" OOP, you can simply swap the wires to ONE of them to get them (generally) in phase. Not perfect probably, but better. Problem with THAT sim though is that the total response curve was made approx. flatter with them oop, so I'd expect a substantial rise in the XO region, meaning that the components will then need adjusting to get the output back closer to flat.

Chris

[XtremeRevolution]

I will switch the wires on the tweeter and see what it sounds like. If I don't like it, I'll pull the crossover and build the newer one he posted that requires more parts. No sense in putting so much time and work into the cabinet to have a speaker that doesn't sound as good as it possibly can. I'll chalk it up as a good learning experience and having a few spare parts.

Even with the way they are though, they still sound better than most anything I've heard come off a store shelf.

Does it make a difference if I swap the wires on the tweeter or on the driver?

[XtremeRevolution]

Chris,

Apparently Patrick had accidentally sent me the wrong crossover for this design. He had two saved; one from before a windows update had restarted his computer, and he sent me the more primitive one the first time. He found the other design and sent it to me. A 12uf cap on the driver and two 6ohm resistors on the tweeter (instead of one 6 and one 10) basically fixes the phase issue and improves FR.

He'll be working on a better XO for me over the weekend as I plan to build a whole lot more of these. Bass output isn't very high but they'd be excellent for a budget 5.1 system.