I am new to this so please bear with me. Also I hope I can get some responses.
I had an AmazonBasics Bluetooth speaker with crushed woofers so I decided to use the card inside to make a better Bluetooth speaker out of 1 old Sony SS-EC50. It sounded quite good, but I quickly learned that it didn't get very loud.
One of my old teachers says I should wire the output from the Bluetooth card to a 3.5mm jack and plug that into an amp which then goes into the speaker. That makes sense to me, however, I'm struggling to find battery powered amps because I still want it portable.
Hopefully someone can help. Thank you in advance!
I had an AmazonBasics Bluetooth speaker with crushed woofers so I decided to use the card inside to make a better Bluetooth speaker out of 1 old Sony SS-EC50. It sounded quite good, but I quickly learned that it didn't get very loud.
One of my old teachers says I should wire the output from the Bluetooth card to a 3.5mm jack and plug that into an amp which then goes into the speaker. That makes sense to me, however, I'm struggling to find battery powered amps because I still want it portable.
Hopefully someone can help. Thank you in advance!
Printed circuit boards (kits) and ready-made amplifiers (ICs) of class AB or D are sold inexpensively on Internet sites. Speakers too. Power can be obtained with a 12V supply.
Develop a project DIY: case, speakers, power (battery) and power supply.
The existing device can be connected to a 100 ohm load followed by a 20 khz PC filter. A small matching transformer can be used.
Усилитель TDA7297 (сборка и подключение) - YouTube
Develop a project DIY: case, speakers, power (battery) and power supply.
The existing device can be connected to a 100 ohm load followed by a 20 khz PC filter. A small matching transformer can be used.
Усилитель TDA7297 (сборка и подключение) - YouTube
The amazon Basics seems to be specified as 2.5W output. That speaker you are using is rated at 50W. This is like trying to pull a freight train with a mini.
Nothing wrong with that, but as your teacher said, you'll need an amp to go between the two if you want to get a reasonable result.
It does not need to be a standalone amp either - there are many amp kits on ebay and the like, for pennies. If you are using battery power, select one that operates at whatever your batteries output (5V or 12V typically) and up to 50W (your speaker's power limit). Just remember that the higher the power, (generally) the more battery it will suck up.
I'd suggest a Class-D module because they are more energy efficient and require less in the way of cooling for a given power. They might not sound as good as class A/AB but you get more play time, and we are talking a mono implementation anyway.
Something like this would be easy to implement: 30W*2 TPA3118 DC 12V-24V D Class Digital Audio Amplifier Board Power Amp Module | eBay
Oh and welcome to DiyA!
Nothing wrong with that, but as your teacher said, you'll need an amp to go between the two if you want to get a reasonable result.
It does not need to be a standalone amp either - there are many amp kits on ebay and the like, for pennies. If you are using battery power, select one that operates at whatever your batteries output (5V or 12V typically) and up to 50W (your speaker's power limit). Just remember that the higher the power, (generally) the more battery it will suck up.
I'd suggest a Class-D module because they are more energy efficient and require less in the way of cooling for a given power. They might not sound as good as class A/AB but you get more play time, and we are talking a mono implementation anyway.
Something like this would be easy to implement: 30W*2 TPA3118 DC 12V-24V D Class Digital Audio Amplifier Board Power Amp Module | eBay
Oh and welcome to DiyA!
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The battery voltage determines the power though, so you should choose that according to the power level you want. For a typical bridged class-D amp 5V will get you 1.5W, 12V 9W, 24V 36W, all into 8 ohms. You're not going to get 50W into 8 ohms from less than 28V,
the formula for bridged class-D is
power <= Vsupply^2 / (2 R)
where R is the speaker impedance, typically 8 or 4.
Hopefully this tags you avtech23. Thank you for the info. If I were to go with the module you recomended, how would you recommend powering it? Thank you again!
Absolutely right, I was just trying to keep things simple.
So for the speaker you have (6 Ohm, 50W max):
24v supply will give: (24*24) / (6*2) = 576 / 12 = 48W theoretical max.
12v supply will give: (12*12) / (6*2) = 144 / 12 = 12W theoretical max.
Just to be clear, the board I suggested is just an example, not an endorsement but something like that should do the job. There are many similar designs available online.
As to powering it, I would personally either get a 6 cell 18650 lithium battery holder with BMS (Battery Management System) and the whole lot could be put installed inside the speaker and made into a standalone unit, or just a plug pack.
Downside for the lithium option is battery life - the amplifier module I mentioned for example has a current draw of up to 3A, so you might get 1 hour or less on battery at full draw depending on the cells you use.
A plug pack would be ideal and can cost around $15-20 and upwards. Obviously the downside is that the speaker will be tethered to an outlet. But often that's not such a big problem. Benefits of using a plug pack are unlimited play time, ease of assembly (most modules have a DC socket) and no exposure to dangerous mains voltages. Plug pack specified amps can be higher than the module specified amps (the module only draws what it needs).