Cherry Inlay Self Powered Voxel Build

[Altoid]

Recently I had a giveaway for a custom speaker. The winner got to choose a custom speaker (within reason) for me to make a custom design on. He really wanted a small subwoofer for his soundbar. I immediately thought about Paul Carmody Voxel subwoofer. However this gentleman really wanted something self powered and pretty. After some discussion and thoughts I came up with this design in sketchup.

Once he approved I went to work. I really wanted a nice smooth finish on this, so I decided I was going to bondo the entire box. Then use whatever paint I want. So that is exactly what I did. But before that, I decided to cut out a spot for a cherry inlay.

I also decided to wire it with this low pass board and this amp with a 19v 4.74a power supply. I also upgraded the knobs to some guitar style knobs. I felt they were heavier duty and fit the look I was going for.

Once it was finished I sealed everything up and laid the inlay. I must say I am very happy with the resutls. I only wish it could stay in my house .


Final Thoughts: I think I may do a redesign on the box. The box is great, but I think the port may be a little too small. I get some port noise and I would like to minimize that. Also if I were to do it again, I would consider adding an anti pop board. When you turn on the amplifier, it does make the speaker pop. However, I am less inclined to do that on a subwoofer, since I typically leave it on all the time. Overal I love how much bass this little sub puts out.

[KEtheredge87]

Nice work sir! I had similar experiences when modifying a voxel sub design to go downfiring and add a Dayton SA70 amp. My port noise issue required a flare on the internal end of the port tube as well to combat noise. It worked out pretty well, as the noise only remained on high output bass passages. Also, the port noise was reduced to a level that could only be heard if you were up close to the port AND you were really listening for it.

Hope your giveaway winner loves the sub! That Cherry Inlay is slick!

[Millstonemike]

When did you buy the pre-amp board? The two different versions offered by PE each have issues.

[xmax]

The ones I got recently worked but both pots seemed to only adjust level. They went into a silly table top vintage
thing and worked fine for the application.

[Altoid]

When did you buy the pre-amp board? The two different versions offered by PE each have issues.

I just bought this a few weeks ago. I knew they had issues, but I really didn't know what other solutions there really were for an application such as this. Do you remember what the issue was with this one?

[Millstonemike]

I just bought this a few weeks ago. I knew they had issues, but I really didn't know what other solutions there really were for an application such as this. Do you remember what the issue was with this one?

The old one had a top LP frequency of 107 Hz. As you lowered the LP frequency, gain was also reduced. Down below 80 Hz caused real issues with the sub gain. PE picked up on that and issued a new version. Gordy bought the new version. From his reading off the component changes on the updated version, I surmised the it shouldn't work at all. Perhaps PE issued a corrected version.

I did a full analysis and modification in this thread. My original analysis implemented a complete overhaul. However the decreasing sub gain with lower LP cutoff can be fixed by simply removing a resistor (on the original version).

It would be helpful if you can post a high res pic of your unit.

[Altoid]

Thanks Mike! There's a lot of great information there. It may take some time for me to digest. I looked to see if I got any real good closeup pictures of the amp, but I did not. It's hard to get a camera in there now. However, I watched video of the amp as I was assembling it and can confirm that it is the exact layout of this board - even missing the 10k resistor. I am not sure which version this is. Based off the video all the values match this board perfectly.

[Millstonemike]

Thanks Mike! There's a lot of great information there. It may take some time for me to digest. I looked to see if I got any real good closeup pictures of the amp, but I did not. It's hard to get a camera in there now. However, I watched video of the amp as I was assembling it and can confirm that it is the exact layout of this board - even missing the 10k resistor. I am not sure which version this is. Based off the video all the values match this board perfectly.

The current picture on the PE site implies they fixed one of the 2nd version's issues as reported by Gordy: replaced a resistor that should not have been removed (correctly leaving just R7 out). But I can't determine the pot values from the pic. That was also an issue with the 2nd version limiting overall gain.

If it does the job for you as-is, enjoy. If not, let me know and we can delve into it further.

BTW: Nice sub.

[Altoid]

Thanks Mike!  I thought i would throw out an update.  The gentleman received the voxel last week and was very happy with it's performance and looks.  As far as I can tell, the board works correctly.  However, I do not have the testing equipment some of you have.  But all in all, the results turned out great.

[Altoid]

I just finished the build video if anyone is interested. I even linked my site if you wanted more information on the build process.