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Let's say that I want to build a mobile phone or a truly AIO (All-in-One) PC based on RPi. Is this possible? If yes, then, please, guide me through the audio issuse, as I am failing on this.

In my research I managed to cover:

  • main unit -- RPi,
  • control -- touch screen,
  • video -- touch screen + camera,
  • communication -- RJ45, Wi-Fi, GPRS, Bluetooth etc.,
  • power -- micro USB cable, battery-based power or PoE HAT,

But I failed completely on:

  • speakers and
  • microphone

because I found no solution that would allow me to connect these two directly to RPi (i.e. not via mini-jack or USB).

Since I am building (at least in theory) a mobile phone or all-in-one station then I am not satisfied by simply connecting some standalone speaker to mini-jack and some also standalone microphone to USB. I know that this is very simple.

I have contacted two local RPi stuff suppliers and both said the same: most likely possible, but never seen something like that and never heard about any parts that could be used within (i.e. mike and speaker as an electronic part, attached to RPi's mainboard).

I want to be able to 3D-print my very own case, put everything inside (including mike and speaker) and build "a box". I want to add an ear and a mouth to my RPi Is this possible at all?

trejder
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  • For a mic you could use an I2S mic like [this](https://www.adafruit.com/product/3421) which has a guide on how to use it with the Pi. There are also I2S amps like [this](https://www.adafruit.com/product/3006) one where you only need to connect a speaker to it. (After connecting the I2S pins to the Pi) – Unsigned_Arduino May 08 '21 at 02:06

1 Answers1

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According to specifications 1 the Raspberry PI has neither an amplifier to support larger speakers, nor an ADC with amplifier for sound input from a microphone.

So you must connect some additional hardware to achieve what you want. There are various HATs than can help you. For example there is from Hifi-Berry a soundcard as HAT, 2. But still you need an amp for supporting larger speakers or you need active speakers.

Update: After comments: If you want to use a low quality speaker with low quality audio you can use the PWM outputs and a filter device to generate output. That kind of filter device is already built in when you use the 3,5 mm Jack. See 3.

Of course you could also solder to get the audio inside. For RPI 3B+ for example you would have to solder to PP25 for left audio channel and PP26 for right audio channel and ground of course, see 4.

For audio input without a additional device you're out of luck, see 5.

Hannes
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  • Thank you. From my perspective your answer answers only half of my question. I have reviewed a wide range of products based on your recommendation, but all of them includes jacks, pins or connectors for connecting _external_ mikes or speakers. Because they're all meant to be a base for a high-quality sound system. I don't need that. The core idea in my question is to have both mike and speakers _internal_. As in: "_put everything inside_". I only need my Pi to barely speak and listen. I want to make a mobile phone or all-in-one PC, not a sound system. – trejder May 07 '21 at 22:46
  • My mike and speakers doesn't have to be of a high quality. Frankly saying, they doesn't have to be of any quality, as long as one of them can generate sound (at a level of speech coming from Skype) and the other one can record it (same here: video call quality). So the question remains: Is there any solution that allows me to have any pair of speakers and mike _inside_ Raspberry Pi? Can you extend your answer to address this issue? – trejder May 07 '21 at 22:47
  • Answer updated. – Hannes May 07 '21 at 23:05