DIY Bluetooth Boombox

Computer and electronic gizmo support.
Post Reply
Sarsippius
Posts: 4336
Joined: Tue Jan 11, 2005 1:13 pm
Location: Darwin

DIY Bluetooth Boombox

Post by Sarsippius »

First a little bit of background, a while ago I bought a little Logitech X50 bluetooth speaker just to listen to some tunes when I wash the car. I had heard one before but I was pleasantly surprised at how good it sounds given how small it is. However I was having to push it to it's limit volume wise so I figured something a bit bigger might be in order. I ended up getting a Harmon Kardon Onyx Mini cheap for $100 but the seed had been planted. I wanted something that sounded good but I guess the emphasis on bluetooth speakers is size and portability and I didn't want to spend $4-500 on something that has compromised sound, you just can't get around physics.

So I started looking at building something that was more like a normal speaker, something like a rectangular box divided internally with some full range drivers or some car speaker splits. I wasn't sure these would turn out well so I started delving into getting separate woofers and tweeters and designing some appropriate enclosures and crossovers but that can become a very deep rabbit hole to dive into.

Then I came across some recommendations to use proven designs that speaker building enthusiasts who have done all the research etc have come up with. This Classix II design was very well regarded, seemed to fit the bill sound wise and was even sold in various kit forms at Parts Express.

https://sites.google.com/site/undefinition/classix-ii

So I went about learning how to use Sketchup and designed something a bit like an old school boombox with a divided section in the middle for an amp and battery. One small snag came up though, of the two Parts Express kits one came with the full un-assembled cabinet, the other with front baffles, neither of which I really wanted as the shipping was much higher due to the extra weight. In the end I grabbed the kit with the baffles as it still worked out the cheapest way to get all the components but it meant rather than a single piece of wood for the front of the boombox I had to go with a slightly weird design as you can see in the pics. It wasn't such a bad thing though as my wood working skills are virtually non existent and cutting and offsetting the holes for the drivers was going to be a real challenge.

https://www.parts-express.com/classix-i ... --300-7110

Parts Express have a cool little amplifier board that is pretty much perfect for this application, while it accepts analog input it also has bluetooth and you can purchase extra modules such as a rechargeable battery extension board, headphone jack and volume knob with cables and led indicator lights.

https://www.parts-express.com/dayton-au ... 0--325-104

Like I say I'm a novice at woodworking but I bought a big sheet of 18mm MDF from Bunnings and got them to make all the cuts for me based off my Sketchup design. The cuts were accurate and using some wood glue and clamps I was able to put the box together. You can see in some of the pics as I was part way through this process. I used a jigsaw to cut the two holes in the back for the ports, they're not great but the ports will hide my cutting skills. I borrowed a circular saw to cut up some of the extra MDF into some pieces to add in the cabinet bracing and then cut up and put in the provided sound dampening (it has adhesive on one side) before gluing the baffles in place.

I'm fairly handy with a soldering iron and I found some examples of how others had put together the speaker crossovers. I used a kinda cool circular layout someone had done with the components just hot glued to a piece of cardboard and with the wires poking through underneath and soldered together. Doesn't look the greatest as you can see in the pics but I've tested them and they all work ok.

Right now I'm at the point where I've sanded the exterior of the box ready to paint on some sanding sealer, I'll then sand this back smooth and apply some dark wood vinyl adhesive to the exterior to make it look pretty ;) The idea with sealing it all and sanding it smooth is so the vinyl adhesive will stick well.

I've ordered some speaker corner protectors to hopefully protect against any bumps and have some rubber feet and a strap handle to carry it around. It's not exactly going to be light but won't be too bad to lug around the place and should sound much better than anything store bought (I've done a little testing without the box fully completed and they do sound good).

Sorry this had ended up a bit of a wall of text and I'm not sure how interesting it will be but thought it'd be good to share. I'll update with some more info and pics once I'm finished.

User avatar
wobblysauce
Seen it, Done it, Invented it!
Posts: 10489
Joined: Thu Aug 25, 2005 9:53 am
Location: On an Island in the south

Re: DIY Bluetooth Boombox

Post by wobblysauce »

Reminds me of this video.
Some play it safe on the merry-go-round, others go for the thrills of the roller-coaster.

ᕙ༼ຈل͜ຈ༽ᕗ vs ლ(ಠ益ಠ)ლ

I have a joke for you. I have a prediction that you are going to walk into a bar, my prediction was wrong and your wallet is gone.
Sarsippius
Posts: 4336
Joined: Tue Jan 11, 2005 1:13 pm
Location: Darwin

Re: DIY Bluetooth Boombox

Post by Sarsippius »

Yeah you can find quite a lot of videos on Youtube of bluetooth speaker builds, good for getting some ideas.
User avatar
wobblysauce
Seen it, Done it, Invented it!
Posts: 10489
Joined: Thu Aug 25, 2005 9:53 am
Location: On an Island in the south

Re: DIY Bluetooth Boombox

Post by wobblysauce »

Pretty much, mostly the same components and just pick what you want to look at.
Some play it safe on the merry-go-round, others go for the thrills of the roller-coaster.

ᕙ༼ຈل͜ຈ༽ᕗ vs ლ(ಠ益ಠ)ლ

I have a joke for you. I have a prediction that you are going to walk into a bar, my prediction was wrong and your wallet is gone.
Sarsippius
Posts: 4336
Joined: Tue Jan 11, 2005 1:13 pm
Location: Darwin

Re: DIY Bluetooth Boombox

Post by Sarsippius »

Well I finally managed to finish off the speaker yesterday.

I didn't take any pictures but I put on a couple coats of the sanding sealer and sanded it down ready to put the vinyl adhesive on. I previously sealed the speaker and vent holes with some paper and masking tape, I wanted to put in the sound damping before gluing the baffles on but didn't want it getting covered with sanding dust.

This is part way through the process of putting on the vinyl adhesive, it was actually fairly easy to put on but the fiddly part was trimming the edges, moreso once getting to a side that was already covered, trying to trim as close as possible but not cut into the existing vinyl.

Image

Vinyl all done, driver and vent holes trimmed and ready to install the drivers.

Image

I pre-drilled some holes and screwed on some rubber feet using some standard speaker screws.

Image

For the carry handle I used a couple bolts, drilled all the way through the MDF and affixed with some nuts on the inside. Some screws just screwed into the MDF wouldn't be strong enough.

Image

Drivers all installed. I soldered everything up to the crossovers, I started soldering to the undersides but it kinda didn't work too well so I ended up soldering to the top side where the components were joined together. The amplifier came with a four pin plug with wires, I'd pre-drilled a couple holes for these to go through to the centre section and sealed them up with hot glue.

Image

I previously cut a piece of 3mm MDF to use as a cover for the centre section, I sealed, sanded and put vinyl on this piece as well and then drilled holes for the various bits to poke through. The amp came with a power switch and I bought the extra modules for the LED lights and the volume knob and headphone jack. I got a DC socket from Jaycar to suit the laptop power supply I bought.

Image

This is a shot of the interior, at the back is the extra module you can buy for the amp which takes 3x 18650 rechargeable batteries, it plugs into the amp board and charges the batteries when power is plugged in. The amp is at the front with everything plugged in, I didn't bother screwing these in, just got some pcb standoffs and hot glued everything down.

Image

Now some glamour shots with everything all complete :D

Image

Image

Image

As for the sound, impressive! The Classix II design has a very good reputation and it is well deserved, I'd read that the bass response is good but I was surprised how deep they go, they seem to go just as low as my floorstanders and the bass seems even a bit warmer. They really sound very good all round and the little amp can drive them to quite a loud level, it's not going to do for a dance party or something like that but they're more than loud enough for what I want would do well for a backyard party or that sort of thing. :yes:
User avatar
KNAPPO
Master artist
Master artist
Posts: 10311
Joined: Sun Jul 17, 2005 1:26 am
Location: North of the dog fence, Adelaide.

Re: DIY Bluetooth Boombox

Post by KNAPPO »

Awesome, they came up a treat.

Well done.
Life is hard...but, life is harder when you're dumb.
User avatar
pixelboy
Posts: 8063
Joined: Tue Dec 14, 2004 4:07 pm
Location: Shitney

Re: DIY Bluetooth Boombox

Post by pixelboy »

Well done.. They look fantastic.. Make me some :up:
eek
User avatar
Cutter
Legend in his own lunchtime
Legend in his own lunchtime
Posts: 3952
Joined: Sat Dec 18, 2004 6:27 am
Location: Location, Location

Re: DIY Bluetooth Boombox

Post by Cutter »

Bloody good work mate, very impressive.
Cutter ~ Carl Rickard

Image
User avatar
wobblysauce
Seen it, Done it, Invented it!
Posts: 10489
Joined: Thu Aug 25, 2005 9:53 am
Location: On an Island in the south

Re: DIY Bluetooth Boombox

Post by wobblysauce »

Nice, like the shots with the media source in it for the scale of size.
Some play it safe on the merry-go-round, others go for the thrills of the roller-coaster.

ᕙ༼ຈل͜ຈ༽ᕗ vs ლ(ಠ益ಠ)ლ

I have a joke for you. I have a prediction that you are going to walk into a bar, my prediction was wrong and your wallet is gone.
Sarsippius
Posts: 4336
Joined: Tue Jan 11, 2005 1:13 pm
Location: Darwin

Re: DIY Bluetooth Boombox

Post by Sarsippius »

Thanks guys I appreciate it, I'm very happy with how they've turned out particularly given it's my first time building something like this from scratch.

Not so much in response to you Wobbly but I took one final pic that gives a better sense of the size. I also decided to weigh them and they come in at 18kg lol :faint: so while they're technically still portable I won't be walking around with it on my shoulder 80's ghetto style :lol:

Image
User avatar
wobblysauce
Seen it, Done it, Invented it!
Posts: 10489
Joined: Thu Aug 25, 2005 9:53 am
Location: On an Island in the south

Re: DIY Bluetooth Boombox

Post by wobblysauce »

Well, you do have that stylish carry strap on it... or is that just for aesthetics.
Some play it safe on the merry-go-round, others go for the thrills of the roller-coaster.

ᕙ༼ຈل͜ຈ༽ᕗ vs ლ(ಠ益ಠ)ლ

I have a joke for you. I have a prediction that you are going to walk into a bar, my prediction was wrong and your wallet is gone.
Post Reply