Raspberry "Pianoputer" ?

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Woody
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Raspberry "Pianoputer" ?

Post by Woody »

Hello everybody !

I'm learning piano (near total noob).

Here is my current "Biography" http://linuxmusicians.com/viewtopic.php?f=12&t=13215

I wonder if attempting to create a Raspberry Pi "Pianoputer" is a good idea ?

Here is my knowledge about the hardware :

- Poor audio output ? (I heard about PWM / only one bit etc)
- Limited computational power (captain obvious :) )
- Low memory
- Low consumption
- Linux available

So far, I know it's a capable machine for playing MP3 / Video etc.

My "SkilZ" :)

I can tweak, search, try, solder, code a lil'bit of this and that (Python and Co).
I'm already a hobbyst with Arduino stuff and I've some Raspberries ready to go.

I have a 88 keys midi keyboard and needed speakers / amp etc.

My goal :

- Create a tiny computer, a kind of "midi expander" dedicated to piano.
- If the sound is "average" it's already very good for me.
- Latency must be very low
- It must be able to run a sampler and a kind of tiny deamon for showing what note is played (coz'I'm'A'noob) :D

My ideas so far :

- Using a DAC in order to shortcut the internal audio : I heard that the RaspPi can't do "massive" polyphony, can I solve the problem with a DAC ? (I think I'll shortcut the RaspPi's PWM stuff with a DAC ?, it's a kind of audio card in fact ?)
- Using a Linux piano sampler and samples with small footprint (something like that ? http://linuxmusicians.com/viewtopic.php?f=50&t=12046)
- Use a very simple Linux distro when the setup is Ok... launching the sampler when starting the card, use GPIO and a button in order to turn off the beast etc.
- Use a "car rearvision" TFT monitor, cheap and tiny (I'll tinker for soldering and so on)

My fears :)

- Massive latency ? I have no idea how it can perform...
- Not enough memory... 512Mo...
- DAC not improving something...
- Jar Jar Binks in StarWars 7 (or any kind of stupid sidekick :-D )

Any guess and tell is welcome :)

May the force be with you !
tramp
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Re: Raspberry "Pianoputer" ?

Post by tramp »

well, to a limited amount that will be possible, have a look here what autostatic does about that:
https://www.youtube.com/watch?v=wUVFfxqXjIc

here you will find some scripts to set things up:
https://github.com/AutoStatic/scripts/tree/rpi

(Most people tend to use a pcduino instead a rapsberry for audio work, . . )
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Woody
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Re: Raspberry "Pianoputer" ?

Post by Woody »

Thanks ! :)

I'll try the same setup, but with a DAC. I'll see if it increases polyphony.
If it does so, it would be marvelous.

About pcDuino, I'm already aware of such boards... the thing is I've already some RaspPi I wanted to use :)

Olimex provides this kind of bord for exemple : https://www.olimex.com/Products/OLinuXi ... e-hardware
Total bargain.. I ordered a lot from them but more for embedded things (alarm systems, automation etc).

Thanks for the script link, I'll not reinvent the wheel :)
tramp
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Re: Raspberry "Pianoputer" ?

Post by tramp »

Woody wrote:Olimex provides this kind of bord for exemple
Oh, a Allwinner A20 Dual Core Cortex-A7 to a really good price, also, thanks for the link. :wink:
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Woody
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Re: Raspberry "Pianoputer" ?

Post by Woody »

You're welcome :)

Olimex is based in Hungaria if I remember well. So it's very easy for us european to order from this location.
Everything is made in Bulgaria, and price is very good. Quality is very high as well.

They're just god of electronic :)
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