Low-pass filter for audio out

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Popcorn
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Re: Low-pass filter for audio out

Post by Popcorn » Tue May 10, 2016 2:19 am

Can someone please tell me again why we just aren't using a $1 USB sound adapter? Seems like we are reinventing the wheel that is on the cart before the horse. :D

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Re: Low-pass filter for audio out

Post by crispy_tofu » Tue May 10, 2016 4:18 am

Popcorn wrote:Can someone please tell me again why we just aren't using a $1 USB sound adapter? Seems like we are reinventing the wheel that is on the cart before the horse. :D
But think of the precious USB ports! ;)

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Re: Low-pass filter for audio out

Post by Fleder » Tue May 10, 2016 6:07 am

Popcorn wrote:Can someone please tell me again why we just aren't using a USB sound adapter? Seems like we are reinventing the wheel that is on the cart before the horse. :D
Do you mean USB Soundcards?
The one i found, that works with Pis is 7,99€ and uses a lot of space (relatively).
And yeah, the USB Port :D

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Re: Low-pass filter for audio out

Post by Popcorn » Tue May 10, 2016 6:18 am

But we are saving the footprint from the custom breadboard that we need to put in there for this PWM audio hack. And that's about the same size.

Anyway, we have 4 ports right?

1) Teensy Keyboard/Gamepad
2) USB Sound Adapter
3) Bluetooth
4) link to external - where I will place my Wifi dongle.

All good, I think. And if we go GPIO instead of the teensy, we gain a port back. What else are you planning to plug into your pi zero?

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Re: Low-pass filter for audio out

Post by the watchmaker » Tue May 10, 2016 6:43 am

Chiz is using one in his project. See 7th picture from the top
http://www.sudomod.com/forum/viewtopic.php?f=9&t=55

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Re: Low-pass filter for audio out

Post by the watchmaker » Tue May 10, 2016 7:06 am

Helder wrote:
the watchmaker wrote:Can someone tell what that middle block is? thanks
It's a double buffer IC, tiny little bugger.
https://www.fairchildsemi.com/products/ ... 7WZ16.html
sorry, And that thing on the right under the headphone-jack?

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Re: Low-pass filter for audio out

Post by the watchmaker » Wed May 11, 2016 1:47 pm

there might be an even easier way. Limmits to mono I think
see:
https://www.reddit.com/r/raspberry_pi/c ... _question/

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Re: Low-pass filter for audio out

Post by crispy_tofu » Wed May 11, 2016 8:20 pm

the watchmaker wrote:
Helder wrote:
the watchmaker wrote:Can someone tell what that middle block is? thanks
It's a double buffer IC, tiny little bugger.
https://www.fairchildsemi.com/products/ ... 7WZ16.html
sorry, And that thing on the right under the headphone-jack?
That's an ultra-fast switching diode, possibly for ESD protection? :|
https://www.fairchildsemi.com/datasheets/BA/BAV99.pdf

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Re: Low-pass filter for audio out

Post by yves1984 » Thu May 12, 2016 11:09 am

is there already a solution für the audio output from the zero?

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Re: Low-pass filter for audio out

Post by crispy_tofu » Thu May 12, 2016 5:39 pm

yves1984 wrote:is there already a solution für the audio output from the zero?
To enable audio on the Pi, either get a USB sound card or build the circuit from this link:
https://learn.adafruit.com/introducing- ... io-outputs

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