My bluetooth speaker project

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the 3 amp was on a lion battery. I have no clue what the amp draw is on the lipo other than it says 35c . But it seems to handle the high volume well, 30 minutes cranking, still cold to the touch both battery and amp. Now I just need to wire up some on/off switch and figure out the wiring so I can keep it hid and still charge some how. Also looking at project box to put the amp in, kinda wish I had bought one that was already enclosed.

As far as sound goes, I compared it to my Sony BTX300 bluetooth speaker, and it blows it out of the water as far as sound goes, way better in the mids and highs. But compared to my Wharfdale studio monitors the bass sounds stressed and distorted. Maybe EQ that out , I need to mess around with bass frequency more until I get it tuned right
 
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Now I just need to wire up some on/off switch and figure out the wiring so I can keep it hid and still charge some how. Also looking at project box to put the amp in, kinda wish I had bought one that was already enclosed.
Very Important > add a pigtail fuse ( an inch or two) close to the battery. You can buy them at an auto parts store.

As far as sound goes, I compared it to my Sony BTX300 bluetooth speaker, and it blows it out of the water as far as sound goes, way better in the mids and highs. But compared to my Wharfdale studio monitors the bass sounds stressed and distorted. Maybe EQ that out , I need to mess around with bass frequency more until I get it tuned right
That's nice. Just looking at it youll have to EQ the base way down or add more cone area down low. Outdoors the situation becomes noticeably worse!
That's why the 'boominator' started with 10" pro drivers and less importantly class-D amps. The road you are starting down has been traveled well by others.
 
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Thanx for the advice infinia, I think I have one of those fuse holders in my parts box.

I also noticed that if I hold my hands over the ports that the bass sounds better to me, more smoother punch. I am going to try out different port sizes, I might have the ports too large.

And my other main challenge now is enclosure for the amp. Again, I rushed and didn't think about the actual size of this particular amp, I remember when first started I was going to use a smaller amp that would fit inside the amp but now I need to build an enclosure that conforms with the wedge shape of the speaker tower, kinda difficult, I tried some aluminum flat plate I had , got it bent pretty close to what I wanted, but decided it wasn't gonna work. I think plastic is going to be easier to get the shape I want.

And I also goofed on my bass speaker watts spec I thought it was 50 watts but its actually 20 watts rms so I will add a voltage regulator to keep the voltage at a steady 12v which should keep the power within the speaker specs
 
And I also goofed on my bass speaker watts spec I thought it was 50 watts but its actually 20 watts rms so I will add a voltage regulator to keep the voltage at a steady 12v which should keep the power within the speaker specs
What amp do you have? I very much doubt a Vregulator will improve things for you esp considering battery power.
Infact most audio folks agree it's always better to have higher watts for the amplifiers than the speakers average ratings, for 'dynamic headroom' and all that.. me i'd use bass EQ like you said earlier. If things start to sound bad or congested simply turn it down.
 
Well if the amp is run at 12 volts it puts out less watts, in my case due to my speaker selection isn't this what I need? Remember my speaker rms on the woofer is 20watts and on the 6 @2 inch speakers 5 watts wired in two sets of 3 parallel I think giving me 15 watts each side. The spec sheet on the TPA3116 shows that if ran at 12 volts it will produce less watts around 15 watts I believe.

Now that being said, it sounded fine at the 16 volts my lipo fed it and most likely I would be fine without a voltage regulator but I figured it would maybe add a safety net in case I or someone cranked the volume up too loud.

I am also going to rebuild the bottom by adding mdf to the sides and bottom, basically to cover up the ports and give me space below the speaker tower to enclose the amp.
 
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Well if the amp is run at 12 volts it puts out less watts, in my case due to my speaker selection isn't this what I need? Remember my speaker rms on the woofer is 20watts and on the 6 @2 inch speakers 5 watts wired in two sets of 3 parallel I think giving me 15 watts each side. The spec sheet on the TPA3116 shows that if ran at 12 volts it will produce less watts around 15 watts I believe.

Now that being said, it sounded fine at the 16 volts my lipo fed it and most likely I would be fine without a voltage regulator but I figured it would maybe add a safety net in case I or someone cranked the volume up too loud.

I am also going to rebuild the bottom by adding mdf to the sides and bottom, basically to cover up the ports and give me space below the speaker tower to enclose the amp.
Closely matching amp power to speaker power is a fools errand. Why? because you don't really know what either of those numbers are from the sales brochures or until you design the speakers inside your box/ port tunings including crossover points and slopes. (yup its like the fake news) You never said if your speakers impedance is either 4 or 8 ohms, AND does that match the amplifier design that you have selected?
FWIW most DIY people that have that chip amp use laptop power bricks 19-20 VDC. but on the other hand most folks try to get the most efficiency and power from their designs. What I do know is adding stuff on power supplies most often results in a big mess. ( BTW IF you can hide another master volume knob IMO a much better solution than " a power supply regulator")
 
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And maybe I should point out the direction of this speaker build. This is to be used as an amp/outdoor speaker, so I play electronica music, keyboard synth and Ipad both going through 4.2 bluetooth.
Oh the bass speaker is 8 0hms and the 2 inch speakers are 20 ohms but wired in parallel brings it down to 6 ohms and this was confirmed with my multimeter. The amp says 4-8 ohms.

And yes this is actually my second but we'll call it my first actual speaker build that I am trying to actually do it somewhat correctly. So I am learning a lot I never knew before.

As far as matching the speakers to the amp, I am trying to get it as close as possible with the available info that I had from the speakers. Only the woofer had full specs , the 2 inchers only had watts and ohms listed. And of course we don't know if the watts were rms or peak. So I figured better to play it safe, keep the wattage to the low side, maybe down the road, I will replace the speakers with all high end.

I also had my bass player come in and listen, he said they sound good but wouldn't hurt to put some eq on the mids and highs. So now I am looking at adding an equalizer to the set up. Maybe like this Pyle Pyle - PLE420P - On the Road - Equalizers - Crossovers

Just gotta figure out what that addition will do to battery power, looks like the wall wart I have will handle both. I also will have to figure on the amp where the bluetooth comes into the amp circuit so I can tie the audio in to the eq and back out again.

Fun challenging stuff I ahead I guess.
 
Ok update, I decided to ditch the eq addition due to difficulty to implement into this particular design.

I also received the 4.2 Bluetooth receiver KCX Bt002 Bluetooth 4.2 Audio Receiver Module Wireless Circuit Board Stereo | eBay

Got it connected powered up ,I left the audio output wires unsoldered until I can figure out how to connect it inline with tha amp,s onboard Bluetooth receiver. Which I am unable to find a pin out for its chip, I figured maybe take the 4.2 output and touch leads off the on boards ic until I hear something....if I don,t blow something up
 
Ok I am just about finished!!

The good: power hook up works perfect, running 14.4 v 4s Lopo with voltage regulator. The sound is decent, I brought it up to my room for an a/b test against my wharfdale studio monitors,overall I am satisfied,just tad more midrange and it would be perfect. Spatial effect sounds great.

The bad: the 4.2 Bluetooth module I added has a high pitched noise,also I wired the power to it off the usb and this might be the problem as It sometimes kicks on the onboard Bluetooth thus cutting it out,I will probably remove it altogether .
The paint job came out like crap. I was using Rustoleum Bedliner the first two cans were a nice matte finish,but the can I got off Amazon which had the same label as my first two was glossy and sandy finish and this was only applied to the bottom half, ’ll live with it.
 

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