First ever build - Overnight Sensations with DIY wooden enclosed amp

[jamurphy880]

Got the Overnight Sensations kit as a birthday gift from the wife. Had never soldered anything before this project. Took probably a couple weekends from glue to finish to crossover and amp build. The speakers and amp were both simply finished with a few coats of clear poly. Had a blast working on this project and they sound great. Well.. we're playing toddler tunes probably 95% of the day. So my kid is listening to some HiFi nursery rhymes and rocks out to them.

The amp enclosure initially worried me because when I received the parts I noticed the binding posts had a good amount of thread depth but the depth of the threads on each of the other parts I needed to install on the amp were all pretty small (the pot/3.5mm jack/DC jack/switch/LED). I was worried I couldn't get the wood of the amp enclosure thin enough without splitting/cracking the wood to get the parts to stay put without glue especially for the jacks because of the inserting and removal of plugs. I did some research attempting to find those same parts that maybe were made to be installed on material thicker than sheet metal but didn't have much luck.

What I ended up doing was glue together two of the three 5"x5"x1" poplar boards and when dry I laid out all the parts (10K audio taper pot, switch, LED, DC jack, 3.5mm jack, four binding posts) and traced an outline. I cut out the interior of the two poplar boards glued together with a drill and coping saw. I didn't have a jigsaw and figured the coping saw would be better anyway to prevent any wood breaking when getting to the thinner parts of the cutout as I could better control the speed and depth of the cut. I followed up with a file on the coping saw cuts to get the wood thickness thin enough for each of those components to secure to the wood properly.

Parts list in case anyone was interested, everything from Parts Express except the last item:
- Overnight Sensations MT Kit
- 8x Dayton Audio BPA-38SN HD Binding Posts (4x for speakers, 4x for amp)
- Audtek Electronics SKRL-16-50 16 AWG OFC Speaker Wire 50 ft.
- TDA7492 Digital Audio Amplifier Board 2x50W
- Parts Express 10K Audio Taper Stereo Potentiometer 1/4" Shaft
- SPDT Mini Toggle Switch
- 3.5mm Stereo Panel Mount Jack
- 2.5mm Metal Panel Mount DC Jack
- LED/knob/18 gauge wire were picked up from a RadioShack going out of business


Please let me know your thoughts!

[bullittstang]

Looks very nice, I like the clear poly finish. Why do you have (aluminum foil??) laying over and around the wires? If it is foil, you need to be certain it doesn't touch the power wire and any other metal, it will short out by completing a circuit.

[jamurphy880]

Looks very nice, I like the clear poly finish. Why do you have (aluminum foil??) laying over and around the wires? If it is foil, you need to be certain it doesn't touch the power wire and any other metal, it will short out by completing a circuit.

Oh wow. I initially had noticed some hum when first firing everything up and someone had suggested using foil to sort of prevent interference if the power wires were touching or in close proximity to the speaker wires? Should I remove the foil then? Thank you for your feedback!

[bullittstang]

I would try twisting the speaker wires and power wires if possible, that create some shielding without actual shielded wires. I would remove any loose metal, just to be safe. If you have hum, that's a sign of a ground loop issue (normally) so you need to re-arrange the wires so the power and signal are as far apart as possible, or shield the signal wires (input signal), as that is what generally picks up interference.
At the very least, wrap some electrical tape around the foil wrapped/close to any power wires.

[wogg]

Looks good! I love those Radio Shack knobs, I've used a bunch of them myself.

[Paul Carmody]

Wait, did you hog out just a solid block of wood for the amp? That's cool!

[jamurphy880]

Wait, did you hog out just a solid block of wood for the amp? That's cool!

Unfortunately, I'm not that cool! But that was the look I was going for. I cut down to three pieces of 5"x5"x1" poplar board, two of which I glued together and after drying, and cut out the pattern for all the components. I then glued on the third piece as the top and a lot of sanding later finished with a few coats of clear poly to match the speakers. Thank you by the way for the speaker design. They sound great!

[stellarelephant]

Wow, awesome look with the natural wood finish and matching amp. Inspirational!

[tomzarbo]

Nice Job, I like how you kept the wood very light in color. The look is classy.

I like the amp case too, that really came out nice. What size power supply did you end up using for the amp?

Great work!

TomZ

[jamurphy880]

Nice Job, I like how you kept the wood very light in color. The look is classy.

I like the amp case too, that really came out nice. What size power supply did you end up using for the amp?

Great work!

TomZ

Thank you! For the amp I ended up using a 24V 4.75A power supply I got here at parts express.