Hi, everyone,
So basically I am dreaming of a very ambitious project which seems mostly impossible right now. So before jumping into the project i just wanted to know more about certain things. That's why i am posting here.
I want build a DAP{or close to a DAP} reusing old android phones giving them some extra life and reducing e waste.
I want to achieve these following things:
1. A DAP or close to DAP level sound quality.
2. A custom Android OS containing only Audiophile related apps and programs and nothing else for clutter free music experience.
Now, I am seeking help from you guys to enlighten me with your knowledge and make this project possible. I am sure that if this project become possible some other enthusiasts might try this and give a fresh breathe to old phones.
Thanks in advance.
So basically I am dreaming of a very ambitious project which seems mostly impossible right now. So before jumping into the project i just wanted to know more about certain things. That's why i am posting here.
I want build a DAP{or close to a DAP} reusing old android phones giving them some extra life and reducing e waste.
I want to achieve these following things:
1. A DAP or close to DAP level sound quality.
2. A custom Android OS containing only Audiophile related apps and programs and nothing else for clutter free music experience.
Now, I am seeking help from you guys to enlighten me with your knowledge and make this project possible. I am sure that if this project become possible some other enthusiasts might try this and give a fresh breathe to old phones.
Thanks in advance.
Hi this is suprising, because this was an idea i was having as well. I was planning on using a smartphone debloating or using a custom rom on it (perhaps even try to have a Bluetooth decoding ability) . Then disassembly the device build a secondary amplifier board where i would use a TPS65131 to essentially leech off the phones own battery. And then get out +-12 voltage and then use that to power the amplifier and use a usb hub chip to act as bridge so that i could charge the device/tranfer files to and then have a secondary port for a usb dac (maybe a cheap Chinese dac or the apple dongle ) to act as a dac and pre amp. And then create a custom enclosure for it (perhaps even hook up 2 batteries in series to increase the run time). Ofcourse my idea would need more time and would requite items a whole another pcb and all. If i do build something I shall surely atleast share it's schematics. On here
You guys have the right idea...I've also been thinking of a good way to DIY a DAP. I have an Anker power bank I plan to use with flat ribbon cables as a battery, and the Moondrop dawn pro as a cheap and small dac/amp. What I need is a usb source that drives a small screen, and android would be good but I'd rather install an extremely lightweight Linux based OS so that it could run on a very small one or two colour OLED. I have a pirate audio headphone amp for the pi zero that I could strip the screen from.
Currently I'm deciding whether to use a RPI zero 2w as the source device and install Volumio, but the case necessary for that would likely be clunky and heavy. I have ordered a faulty iPod classic that I intend to strip the guts from and see if I can somehow fit everything in there. Then I will Dremel around the 30 pin charging port to fit the dawn pros PCB and the charging port. I will let you know how it goes.
Wishing you both the best of luck!
Currently I'm deciding whether to use a RPI zero 2w as the source device and install Volumio, but the case necessary for that would likely be clunky and heavy. I have ordered a faulty iPod classic that I intend to strip the guts from and see if I can somehow fit everything in there. Then I will Dremel around the 30 pin charging port to fit the dawn pros PCB and the charging port. I will let you know how it goes.
Wishing you both the best of luck!
Hi,
it's not based on a phone, but I "built" a DAP (only the software) using a cheap Wio terminal as hardware, driving USB DACs (I have UAC1 IFI goBlu, UAC2 Shanling UA1+, Colorfly M1P) .
The UI is far from being as nice as commercially available models, because I put all the effort on making it fast and efficient.
It's able to playback RIFF/WAV and FLAC at 16b/44.1kHz with a (downclocked) 64MHz microcontroller and 192kB of RAM, and can accomodate up to ~10000 audio files from an exFAT sdcard (currently I'm using a 512GB sdcard that's half full with 7.7k+ audio files and a few thousands various non audio files).
I started this project when I read a long time ago (8 years maybe) that high end DAPs would need up to 2 minutes to parse a 32GB sdcard when inserted for the first time. I was wondering what took so long when you have a cortex-A type of CPU running at 800+MHz, 2 minutes is a huge amount of CPU cycles.
I posted a short video on youtube
Cheers
it's not based on a phone, but I "built" a DAP (only the software) using a cheap Wio terminal as hardware, driving USB DACs (I have UAC1 IFI goBlu, UAC2 Shanling UA1+, Colorfly M1P) .
The UI is far from being as nice as commercially available models, because I put all the effort on making it fast and efficient.
It's able to playback RIFF/WAV and FLAC at 16b/44.1kHz with a (downclocked) 64MHz microcontroller and 192kB of RAM, and can accomodate up to ~10000 audio files from an exFAT sdcard (currently I'm using a 512GB sdcard that's half full with 7.7k+ audio files and a few thousands various non audio files).
I started this project when I read a long time ago (8 years maybe) that high end DAPs would need up to 2 minutes to parse a 32GB sdcard when inserted for the first time. I was wondering what took so long when you have a cortex-A type of CPU running at 800+MHz, 2 minutes is a huge amount of CPU cycles.
I posted a short video on youtube
Cheers
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Damn that ui is pretty bare bones but that speed is really impressive. As far on the topic of a linux based os for a lightweight ui. I am of the belief of we actually strip out an older version of Android (as we aren't connecting it to the internet even something as old as 6 (but preferably 9) will work (we want something after 5.1 as project butter was introduced post 5). As a lightweight framework and then use a pre-existing media player as the ui and the be done with it. (Though one feature we would be missing is Bluetooth decoding as I am yet to find a way to get that working on a normal Android phone)
Yes the UI is very simplistic, because I don't really care about the UI on a DAP.
I just want it to be fast, efficient and reliable. I'm probably not gonna spend 1% of the time looking at the screen, just listening to music.
There used to be DAPs with very simple UI, such as the Shozy Alien+, and I loved the concept. It means longer battery life, too.
Now I agree that if you integrate more complex services such as e.g. spotify, such a basic UI is probably not gonna be sufficient.
I just want it to be fast, efficient and reliable. I'm probably not gonna spend 1% of the time looking at the screen, just listening to music.
There used to be DAPs with very simple UI, such as the Shozy Alien+, and I loved the concept. It means longer battery life, too.
Now I agree that if you integrate more complex services such as e.g. spotify, such a basic UI is probably not gonna be sufficient.