Portable Bluetooth Speaker Build With Passive Radiators Build

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Hey, looks great, a lot of effort and well executed!
Tho, it could have been planned a bit better imo.
As mentioned, ADAU1701-DSP Boards or similar are the way to go. Well above beyond anything active circuits could achieve here.
MDF should not be used in such portable applications imo, too heavy, too easy to destroy. Better go for plywood or something. If you are using a CNC/3D-printer anyway, i'd recommend a well braced plastic enclosure. Could reduce your outer volume a lot!

regards!
 
Hey Guys,

Sorry for the lack of updates

Assembled one crossover and been listening for a while, without doubt is the best sounding speaker I've made so far, full sound without being fatiguing whatsoever, all the work done with the measurements really paid off, and thanks a lot to kimmosto for the amazing software and the tips, mainly about my first crossover layout that had a not so good power response.

I bet that if I had went with that design the listening experience wouldn't be so pleasuring, I say that because the speaker has a great definition, the highs are really present, but a bit more than that and it would be bad

An externally hosted image should be here but it was not working when we last tested it.


Also used varnish on the laminated one and really liked the end result

An externally hosted image should be here but it was not working when we last tested it.


An externally hosted image should be here but it was not working when we last tested it.


Now, a few issues, the TDA7498 is being used to the limit at high levels, the high boost in the bass causes distortion in the highs, if I sense that I need to operate them louder I will get another amp and make them bi-amped

Second, the idle current consumption is a bit high, 100 mA, for the outlet powered one that's fine, but for mine that will be powered by battery's would be great to lower that, I will see if I can find some low power op amps, still, 33 h battery life at low volume is great, and 7 h or more at full power

I'd like to finish one of them since my father's birthday is in 10 days, I don't know if it will be possible, I predict that making the grill fit nicely will involve a lot of work, besides that I just need to assemble the second crossover and put everything inside


I am just starting with sigma studio to use that board. they are $18 on ebay!

Good to know, I may try them.

Played around a bit with Sigma studi, but not quite sure if I would manage to do the band limited limiter

Hey, looks great, a lot of effort and well executed!
Tho, it could have been planned a bit better imo.
As mentioned, ADAU1701-DSP Boards or similar are the way to go. Well above beyond anything active circuits could achieve here.
MDF should not be used in such portable applications imo, too heavy, too easy to destroy. Better go for plywood or something. If you are using a CNC/3D-printer anyway, i'd recommend a well braced plastic enclosure. Could reduce your outer volume a lot!

regards!

Thanks, this is more a learning exercise, since the first portable speaker I've made I wanted to make a equalizer PCB like this, so going DSP would defeat that purpose, and was a great project to test the quality of JLCPCB

I think I need to clarify the portable I have in mind, my fathers one will stand in his desk at all times, mine I will use around the house and mainly in the workshop, if I take them out will be a few times a year for a barbecue os something like that, it's not portable in the sense to go camping or take to a festival, compact battery powered speaker would be a more appropriate term

Would love do to a full printed speaker, unfortunately my printer is no big enough and it would take a lot of time to print, I may try some smaller project with this idea

Actually, the box itself is quite light using 9mm MDF, is has a lot of holes for the drivers and passive radiators, and they weight a lot more than the box, each passive radiator needs 80g to achieve the 40Hz tunning

Awesome, looking at the photo's I felt jealous hahaha I'm still stuck on my bluetooth speaker jbl and doss soundbox touch I wish I can make my own like that someday :) great work by the way!

Thanks, I have a JBL flip 4 and have to say for the size the sound is really good, use it a lot around the house and attached to my backpack when riding a bike or skating
 
Just a long overdue update

Still no finished, lots of headache trying to connect the bluetooth module, burned 4 of them so far, so I closed it up and using only the analog input

What I can say is that there isn't anyone who wasn't impressed by listening it in this few months

I bought a higher quality module and hope it will work, this way I can finish the one for my father and start working on mine

Speaking of that, I'm going full active in it, two TDA7498 boards and a ADAU1701 board from Sure

This is what I have so far, the main modification is I will cut the whole bottom off and make a removable aluminum plate to house all electronics, easier to assemble and maintain if needed

Since I've never done an active speaker I may have done something wrong on the crossover

An externally hosted image should be here but it was not working when we last tested it.


An externally hosted image should be here but it was not working when we last tested it.
 
How is it going for you?

One box is finished, I gave up on the Bluetooth and optical in, it will be an external module with external power supply

It looks and sounds amazing, I had the opportunity to let it play in a open space where room modes are non existent and oh boy, almost nobody believed that such full sound was coming for this small speaker, I will see if I can record a video

There are a few issues that I hope to resolve when building mine, two to be precise, first, the grill vibrate at full volume on certain songs, since mine will have even more power I have to fix it, and two is that the cloth is not perfectly flat in some places

1hiep0 asked for the Hornresp input so I'm adding them bellow

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Progress after a long hiatus

Having the ADU1701 accessible is a must, so I made a receptacle that allows it to be programmable without opening the whole speaker. Battery structure is also done

I made the cutout on the bottom that will be covered by a aluminum sheet, this way its easy to work on the electronics, I really need to solve the Bluetooth problem in this one, everything will be hooked up using connectors





 
To make things easier I made the wiring schematic, mainly to avoid mistakes when selecting the connectors

The initial plan was to use and Arduíno for state of charge indication and a few other things, but after diving in the SigmaStudio it's really simple to do using the ADAU1701

One thing missing from the schematic is a voltage divider so I can read battery voltage and drive the leds

I may implement a soft latch driven by the ADAU so it can turn everything off when the battery is depleted

The green region is the rear panel, 12 pins needed, probably will keep the audio and leds on their own connector, so 3+6+3 pins needed

On the red it's the speaker cabinet itself with the drivers, 8 pins needed

I will first experiment by doing a proper star ground and see if the problems with Bluetooth noise go away, if not I will try again with a isolated DC-DC converter, it makes no sense, but it didn't help in my last try

 
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