I have used the ND65-4 in a few builds and have been pretty impressed with them. Most of the time, I just used them in a sealed enclosure, as I tried to keep the size down. This time, I decided to use a 1″ port.
My friend was having a home warming party and wanted me to bring a few speakers. Since, he has seen all the speakers I have already built, i decided to bring something new to this party. And since this was a happy celebration, why not an Emoji? Since this party was going to be held outside, I made this a portable unit with batteries. However, you could do without this if you do not need the portability aspect.
2 – Dayton ND65-4
1 – 1″ Port
1- DC Jack
2 – 0.38 Ohm Inductors (no longer available – 0.4 air core Inductor
1 – 12″ Concrete Forming Tube
2 – 1/2″ pieces of MDF
First I took the 12″ concrete forming tube and cut it to 3 2/3.” Next I took my Jasper Circle cutter and cut two pieces of 1/2″ MDF that would fit inside the concrete forming tube. In my case, I had to make them 11.5″ outside diameter. Based off my calculations, the resulting volume should be about 0.16 cubic feet. However, once we add in the rear mounted speakers, the amp and the battery pack we would be closer to .15. This is about perfect for these speakers.
So I proceeded to cut out holes for both speakers, and a hole for the port. I was careful to line up the holes perfectly, in order to make the face. On the rear panel I cut out a rectangle that could be removed, if you ever needed to get in the speaker. And added a few holes for the power jack and the 3.5mm jack. I also applied a 3/8 round over to the speaker holes. next I cut the 1″ port to about 3″, which should tune it to about 60hz.
Finally, I started assembling it. I glued on the front. Once that was dried, I painted the front and back separately. I did seal it first with a little bondo. I used bright yellow Krylon paint, but I do not recommend that brand. It was on sale, but I personally did not enjoy using it. I will go back to my good old trust Rustoleum on my next project.
Once the paint is to your liking you will need to hook start installing everything. Everything is installed fairly straight forward. I did add a BSC to the driver. You will need to take one 4 ohm resistor and a .38 inductor and solder both ends together (aka parallel). This will go in-line with the positive (aka in series) wire of one of the woofers. Now do the same thing to the other woofer. Glue on the back and you are finished.
I am extremely impressed with this speaker. The amount of bass this puts out is unbelievable for it’s sized speakers. Everyone at the party was shocked at the sound quality. They just sound much bigger than they are. In fact, numerous people asked me how much this build cost and were in shock with the cost of the it. It just sounds a lot better than you would imagine for the size speakers.
Of course, you do not have to build an “Emoji” if you do not want. Just keep the relative volume, and you will be happy. Also, I will have a build log Video coming later as well as sound demonstration. Until then, ask any questions you want.