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I am thinking of using a speaker with Raspberry Pi 3b+ which has a 5V output pin.

Speaker data:

  • Power rating (RMS) 30 Watts

  • Power rating (max) 60 Watts

  • Impedance 8 ohms

Will this speaker will work with 5V and 2A?

This is the speaker:

Peerless by Tymphany TC9FD18-08 3-1/2" Full Range Paper Cone Woofer

Speaker

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  • \$\begingroup\$ It is unclear what that speaker is, is it an active speaker (built in amplifier) or is it an unamplified speaker? Add a link to the model. If the speaker is active, the headphone output of an RPi can drive it. If it is a passive speaker you will need an audio amplifier module, for example a LM386 based module. That can work on 5 V. \$\endgroup\$ – Bimpelrekkie Apr 15 at 10:02
  • \$\begingroup\$ This Is the Speaker " parts-express.com/… " and This also " parts-express.com/… " \$\endgroup\$ – El_Dorado Apr 15 at 10:03
  • \$\begingroup\$ So the speaker is only a driver, then you will need a audio power amplifier module, for example an LM386 based module like: banggood.com/… You can power that from 5 V. You will not get 30 W audio power from that but that is nearly impossible from 5 V so it might not be very loud. \$\endgroup\$ – Bimpelrekkie Apr 15 at 10:06
  • \$\begingroup\$ So these Speakers will work Fine with the Raspberry Pi with a Power Amplifier Module? Like: " Adafruit I2S 3W Class D Amplifier Breakout - MAX98357A " \$\endgroup\$ – El_Dorado Apr 15 at 10:08
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Will this speaker will work with 5V and 2A?

Yes, but the maximum average output power will be less than 30 watts; a 5 volt supply capable of delivering a maximum of 2 amps can only produce 10 watts and, given that your amplifier will have an efficiency around 60%, the maximum power delivered from the 5 volt supply will be about 6 watts.

But it's slightly worse than this if you use a conventional linear amplifier because it can only produce maybe 4 volts peak-to-peak and that, as a sinewave, has an RMS value of 1.414 volts. That RMS voltage across an 8 ohm speaker produces a power of only 0.25 watts.

If you used a bridge amplifier you could achieve maybe 8 volts p-p and that would deliver a sinewave power of 1 watt.

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    \$\begingroup\$ In general, I am Not from an Electrical background so your Explanation Bounced above my Head. Sorry For that. Can you Explain in Simple terms. \$\endgroup\$ – El_Dorado Apr 15 at 10:09
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    \$\begingroup\$ They are about as simple as I can muster. \$\endgroup\$ – Andy aka Apr 15 at 10:10
  • \$\begingroup\$ Ok, I have Added Speakers Link in above Comments can you say if they will work or Not with the amplifier I have suggested above? \$\endgroup\$ – El_Dorado Apr 15 at 10:12
  • \$\begingroup\$ This are the Speakers : " parts-express.com/… " and " parts-express.com/… " and Amplifier : " Adafruit I2S 3W Class D Amplifier Breakout - MAX98357A " \$\endgroup\$ – El_Dorado Apr 15 at 10:13
  • \$\begingroup\$ From a 5 volt supply you will get 1.8 watts into an 8 ohm speaker at 10% distortion (it's all there in the Adafruit details). If you expect some level of high-fidelity then you can't expect more than about 1 watt (as per my answer). Given that your speaker is rated for 30 watts you will be significantly under-utilizing its capabilities. \$\endgroup\$ – Andy aka Apr 15 at 10:16
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From the way youve written your question im assuming youre trying to hook the speaker up to one of the Pis GPIO pins and the 5V 2A supply is whats powering the PI. The answer to that is no, youll fry the pi. The amount of power available out of the GPIO pins is not the same as the power supply going into the pi. The max output current of a pi 3 gpio pin is approx 16mA. As your speaker is 8 ohm it will try to draw 412mA.

You will require an amplifier to meet the power demands of a speaker. For 8 ohm at 5V then the power output will be v^2 / R = 25 / 8 = 3.125W So the speaker will work but it will be quieter

For more understanding I would suggest this article: Speaker power article

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  • \$\begingroup\$ I have added the Speakers in Above Comments Can You please refer it and Suggest me. \$\endgroup\$ – El_Dorado Apr 15 at 10:06
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    \$\begingroup\$ What do you want me to suggest? my answer and the (better) answer by Andy aka still stands even with the information youve added. When you mention the 5v output pin, what pin is that? maybe a diagram or schematic of what youre trying to do might help \$\endgroup\$ – Andy West Apr 15 at 10:12
  • \$\begingroup\$ If youre not from an EE background and just want some speakers for your pi then why not use the audio jack and something like this? uk.rs-online.com/web/p/pc-speakers/7302732 \$\endgroup\$ – Andy West Apr 15 at 10:13
  • \$\begingroup\$ Because I am creating a voice assistant and need Speaker Which can Speak Clearly so.. And the pin is power supply 5V GPIO of Raspberry Pi. \$\endgroup\$ – El_Dorado Apr 15 at 10:14
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    \$\begingroup\$ A GPIO cannot provide 2A output. \$\endgroup\$ – JRE Apr 15 at 10:18
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  1. The Raspberry Pi outputs are 5V, but nowhere near 2A. More like some tens of milliamperes.

  2. 5V at 2A is only 10 watts, so it would be safe to operate that speaker from an amplifier operated from 5V.

  3. 5V into 8 ohms can only push 0.6 A through the speaker, so you can only get like three watts RMS into an 8 ohm speaker from an amplifier operating on 5V.

If you want to make full use of the speaker's rated power then you will need an amplifier capable of providing that power.

The Raspberry Pi can't provide that power. A typical Raspberry Pi has a 5V powersupply rated for 2A. That's only 10 watts so it's nowhere near the rated power - and you can't even get that because the voltage is too low for the speaker impedance.


30 watts RMS is ********* loud.

Had to work on a bunch of radios once. Speakers were rated for 12W RMS, and the amplifiers could provide it.

Some jerk set the (push button controlled) volume all the way up to maximum before disconnecting the things and sending them to the company I worked for.

The only way to turn down the volume was to power up the radio and use the push buttons.

Problem was, the darned things played this 5 second long "Gong" sound at power on.

The first one I ran into like that near blew my ear drums out. It rattled the windows, and made people in other companies in the building come over and ask what happened.

I cursed over the second one.

At the third one, I cursed the technician who had removed the radios from the police cars because it was obvious he had cranked up the volume on them on purpose.

Thereafter, power up of each radio consisted of placing the speaker face down in the cushions of my chair, me sitting on it, turning on the radio, and waiting for the gong to end.

The equipment belonged to the customer. I couldn't modify the cable set to disconnect the speaker, and you had to have the whole cable set to get the radios powered up to the point you could turn down the volume.

My buns were numb from the vibrations before I got all the radios powered on and checked (and the volume turned down.)

And, that was only 12W RMS. Not 30W like you want to use.

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  • \$\begingroup\$ My second Suggested Speaker is of 12WATT and 8ohm wil it work? \$\endgroup\$ – El_Dorado Apr 15 at 10:20
  • \$\begingroup\$ It won't work any better. Power out of a GPIO pin is like 0.08 watts, and if you connect it straight to the speaker it'll probably burn out the GPIO pin. You must have an amplifier between the Pi and the speaker. \$\endgroup\$ – JRE Apr 15 at 10:25
  • \$\begingroup\$ Yeah Going to use Adrafruit provided AMplifier : Adafruit I2S 3W Class D Amplifier Breakout - MAX98357A \$\endgroup\$ – El_Dorado Apr 15 at 10:26
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    \$\begingroup\$ For Pete's sake: Buy a simple USB sound card for the Pi. Buy a simple powered speaker (it contains an amplifier.) Use standard software and drivers on the Pi to make your sounds. \$\endgroup\$ – JRE Apr 15 at 10:35
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    \$\begingroup\$ Good. Just connect a powered speaker to the 3.5mm jack. \$\endgroup\$ – JRE Apr 15 at 10:37

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