DIY dual Dayton 10" sealed subs - piano black

[Tim D.]

I completed a DIY subwoofer project recently and wanted to share my pictures. Anytime I do a project, I always rely on these threads from others to get me through it, so hopefully this will be of use to someone else.

My goal with this project was to build 2 "smallish" musical subwoofers to go in my dedicated 2 channel room. I went with a sealed design for its tighter bass and better musical performance, and because it allowed the footprint to stay relatively small. The design was loosely based on one of John Krutke's subs, but I used different drivers, different amp, and different dimensions/internal volume. I also wanted to finish them with the high gloss, piano black look. Figuring out how to do that took a lot of time spend reading on the forums since there are so many ways of doing it. In the end, due to constraints of where I had to spray the paint and the equipment I had available to me, I went with Crystalac paint. More details on that part will come later.

I went with Dayton RSS265HF-4 10" drivers and Dayton SA240-B 240W amps. Parts express has the drivers on sale for $125 and the amps on sale for $99, so I thought that was a pretty good deal. I built the cabinets out of ?? MDF with the front baffles being 1 ?? MDF. They are right around 16? cubed, with a net internal volume of 1 cubic foot. I used one of the software programs (I can?t remember the name right now) to help determine what the optimal internal volume for those drivers would be. Enjoy, and let me know if you have any questions.

The cut MDF pieces ready to begin assembly. These were cut on my table saw.


Gluing together the front baffle pieces.


Sides glued to the base.


Amp brace in rear installed.




Internal bracing installed.




Checking the fit of the amp on the back panel. The opening was cut with my plunge router.


Gluing on the top.


Installing the nuts on the back side of the baffle for the driver screws.


Sealing the MDF on the inside with Bulls Eye sanding sealer.


Gluing on the front baffle and back panel. I glued the back with the amp in place to ensure proper alignment with the amp brace inside.




All edges were rounded over with a 1/2? router bit.


Now on to the finishing process.

[Tim D.]

Now that the boxes were all completed, I turned my attention to the finish. One important thing to remember when attempting a piano gloss finish is that every little impurity in the wood below is going to show through. After thoroughly sanding the boxes up to 400 grit, I started working on the edges/seams of the MDF. These had to be covered somehow so that they didn?t show through the finish. I did this with Bondo glazing and spot putty. It worked pretty well, but required a lot of patience as it wasn?t very easy to work with and was very messy. I applied 4 coats with a putty knife, sanding between each coat. In the end, it did create a nice smooth surface that hid the seams.


After the Bondo was applied and sanded, I sprayed 3-4 coats of the sanding sealer on all the exterior surfaces then sanded it all down again.


I was now ready to paint. The only problem was that it was still cold outside and the Crystalac paint needed to be sprayed at a minimum of 60-70 degrees, so I couldn?t do it outside. Not wanting to wait until spring (and since the paint is water based), I decided to transform my music room into a temporary painting room. I lined the ceiling of floor with plastic and built some plastic walls. Not pretty, but it worked fairly well.





I sprayed 10 coats of Crystalac Satin Black Topcoat, dry sanding every 3-4 coats with 400 grit. All my sanding during the finishing phase was done by hand with a rubber sanding block. Next I sprayed 12 coats of Crystalac Clear Gloss 2001, no sanding between coats. Since I didn?t have a spray gun or compressor (and didn?t want to buy one), I used the Preval spray cans you can get at Home Depot. They are basically just compressed air cans that screw on top of a glass jar that you pour your paint into. It only costs $4 for each replacement air can, and I think I used 8 of them for the whole project. Probably not as good as a professional paint system, but the results were very nice for the money spent. Here are the boxes after the painting was complete (before any sanding or finishing).



Next up was the wet sanding stage. I wet sanded first with 1000 grit, then 2000 grit. The goal here was to remove all the orange peel from the paint, which I didn?t completely accomplish. I think if I had done more stages of sanding, I could have removed more of the orange peel. I would probably recommend doing 800, 1200, 1500, and 2000 grits if you do the same thing.



Next, I applied Meguiars Rubbing Compound using a finishing cloth. I did small sections at a time, applied a small amount of compound, and buffed it out until it turned to a dry paste. This brought back the gloss and started to create a mirror image, although not a completely sharp one yet.







Finally, I applied Meguiars Ultra Finishing Polish using the same method as the rubbing compound. This refined the mirror image, gave it more contrast and made it sharper.





Back up in the room and ready to install the components.


Amps installed.


Acousti-stuff poly fill loaded in. 1 bag per sub.


Drivers installed.


Subs installed into the system. I am running high level speaker cables out of the integrated amp into the sub which is doing the cross over and passing the rest of the signal on to the speakers. I have the crossover set at 80Hz. One important aspect when I was looking for a sub amp was it had to have high level In and Out connections with a crossover because that was the only option with my amp.





As far as sound goes, they are exactly what I was looking for. They gave me the extra bottom end that my Zaph SR-71s were missing in a very controlled and musical way. I am hearing the full range on my music now and it is awesome! A quick recap of the costs of the project (for 2 subs):
*Drivers: 2x at $125 = $250
*Amps : 2x at $100 = $200
*MDF: 4x8 sheet = $50
*Bondo, wood glue, sandpaper, Preval spray cans, rubbing compound, polish, finishing towels = $150
*Crystalac (black satin and clear gloss quart each, viscosity reducer) = $70
*Total Cost = $720 ($360 each)

Well, that's it. I hope this is helpful to someone else looking to do something similar. Let me know if you have any questions.

[codyc1ark]

Very nice! Great write-up, very clean pics, impressive!

Doh! Forgot to add - I love your paintbooth, you need to be marketing these!

[del44]

Very nice job. I like the way you took your time and did it right.

[halo71]

Very nice subs you built! I really like that last pic of your set up. Very clean.


Perhaps a dumb question. But why did you coat the inside of the cabinet with sanding sealer?

[steveinaz]

Beautiful work!

[DaveMuell]

I'm very impressed. Nice work.

[FTGV]

Very nice,the extra work involved doing the piano finish was worth it, they look great.Love that make shift spray booth.
I bet they sound good in combo with the Zaphs.

[Conradicles]

Great job!

[Tim D.]

Thanks everyone! It was a fun project.

To answer halo71's question: I probably didn't have to seal the inside with the sanding sealer, but I had just read so much that any amount of moisture could cause the MDF to warp, I didn't want to take a chance. It didn't cost me anything extra and it didn't take much time, so I guess it didn't hurt anything.

[gdpeck]

I like your car.

Also, the subs are completely awesome. I hate hand sanding worse than almost everything, so I will probably never attempt a project like this, but I have a lot of admiration for anyone who can pull it off. Enjoy the fruits of your efforts.

George

[mdaudioguy]

That's some great work! I'm especially impressed that you don't appear to have a dedicated workshop! You definitely have the right to be proud with your results.

[jinjuku]

Nice to see another Zaph affecionado here. I have the ZDT 3.5's and one of his ZAW14 based center channels built.

Good thing for me personally that I'm not a fan of gloss finishes. Satin all the way for me and less work

The subs look awesome. I believe Zaphs sub is based on a Peerless woofer which the Daytons you used are a direct shot at. It has to sound phenomonal with the SR 71's.

[Toolfan66]

Very Nice Job!!!!! I freaking love it!!!!


Enjoy!!

[slammin86]

Very nice job.

[Tim D.]

That's some great work! I'm especially impressed that you don't appear to have a dedicated workshop! You definitely have the right to be proud with your results.

Thanks! You are certainly right about not having a shop. A majority of this project and my Zaph SR-71 speaker build (http://www.polkaudio.com/forums/showthread.php?t=95990) was done in my music room, which is just a spare bedroom.

[audiocr381ve]

Wow. Are you self-taught?

[Tim D.]

Nice to see another Zaph affecionado here. I have the ZDT 3.5's and one of his ZAW14 based center channels built.

Good thing for me personally that I'm not a fan of gloss finishes. Satin all the way for me and less work

The subs look awesome. I believe Zaphs sub is based on a Peerless woofer which the Daytons you used are a direct shot at. It has to sound phenomonal with the SR 71's.

The Zaph designs are great, and such a wonderful resource to the DIY community. How do you like your ZDT 3.5's? Do you have any pictures of them?

The design I was looking at for these subs was in Zaph's archives and it was called Dayton RSS315HF subwoofer with 500 watt amp. I followed the shape and internal bracing structure, but modified so they could be smaller.

I had read these Dayton's would be a good match to the SR-71's, and they definitely are. They integrate seamlessly with the speakers and sound awesome together

[jinjuku]

The Zaph designs are great, and such a wonderful resource to the DIY community. How do you like your ZDT 3.5's? Do you have any pictures of them?

The design I was looking at for these subs was in Zaph's archives and it was called Dayton RSS315HF subwoofer with 500 watt amp. I followed the shape and internal bracing structure, but modified so they could be smaller.

I had read these Dayton's would be a good match to the SR-71's, and they definitely are. They integrate seamlessly with the speakers and sound awesome together

I love my ZDT3.5's. They are very neutral, transparent and get out of the way.

Here is a pic of the center (along with Zaphs' ZA5.3c)

I am in process of redoing the l/r cabinets now that I have a local source for wood veneered MDF (yeah!).

Here is the thread on my Statements build.

[Tim D.]

Wow. Are you self-taught?

I am "internet-taught"

Learned everything I needed from the forums and others who did something similar. Before I did the speaker build, I didn't even have any power tools. I decided I wanted to build some speakers, so I got a table saw, router, and sander and I was good to go.

[Tim D.]

I love my ZDT3.5's. They are very neutral, transparent and get out of the way.

Here is a pic of the center (along with Zaphs' ZA5.3c)

I am in process of redoing the l/r cabinets now that I have a local source for wood veneered MDF (yeah!).

Here is the thread on my Statements build.

The Statements are looking great! Can't wait to see the finished product. I have read great things about those speakers.

[jinjuku]

I am "internet-taught"

Learned everything I needed from the forums and others who did something similar. Before I did the speaker build, I didn't even have any power tools. I decided I wanted to build some speakers, so I got a table saw, router, and sander and I was good to go.

You must be my evil twin.

[Upstatemax]

I think you might have inspired me to build my own sub...

I already have all the tools I would need, now I just need to find time!

[geoff727]

Outstanding!

I've subscribed to this thread to remember where it is.

G~

[Tim D.]

I think you might have inspired me to build my own sub...

I already have all the tools I would need, now I just need to find time!

You should definetly go for it! It really was not a difficult project, and was much easier than the speaker build IMO. Just makes sure you take your time and don't try to rush through any of the steps. Doing to project is very fun, but the satisfaction of listening to what you have made and it sounding so good is very satisfying.

[Toxis]

What was the reason for not using any screws in the enclosure? I would think it was to keep the finish smooth and less smoothing/sanding but wouldn't it keep it tighter? Or maybe if you don't get on it (HT style) you don't need a box to hold as much pressure...?

[dorokusai]

Excellent work. Why not an X brace inside or alternative to the bracket style? Just wondering since you have the skills and equipment.

[rooftop59]

Those look incredible.

Any in-room measurements of the finished subs?

[jinjuku]

What was the reason for not using any screws in the enclosure? I would think it was to keep the finish smooth and less smoothing/sanding but wouldn't it keep it tighter? Or maybe if you don't get on it (HT style) you don't need a box to hold as much pressure...?

No need for mechanical fasteners in speaker cabinet building. Proper joinery and wood glue is more than of a sufficient mechanical bond to keep it together.

Wood glue is of such a nature that the wood will give out before the glue. See my Statements build thread. All dado and glue.

I've been feeding my 3.5 cubic foot sealed subs with 1200 watts per channel for a couple of years now.

[dorokusai]

Agreed. It took a very wise man to teach me the finer points of proper wood fastening, and to have faith in them....and who'd a thunk it, he's a finer member of the board to boot.