[drummerdimitri]

I am wondering why my OTG cable that connects my phone to USB devices wont work with my RSA predator amp/dac if using USB dac as input from the phone.
 
The AQ dragonfly works this way so does the device need to support it with hardware or what?
 
The OTG cable works as external storage but I'd like to use it with my predator from my phone.
 
Can this be done? If not why?

 

[ClieOS]

  I am wondering why my OTG cable that connects my phone to USB devices wont work with my RSA predator amp/dac if using USB dac as input from the phone.
 
The AQ dragonfly works this way so does the device need to support it with hardware or what?
 
The OTG cable works as external storage but I'd like to use it with my predator from my phone.
 
Can this be done? If not why?

 
It all depends on how much power is being drew over the USB connection.
 
Newer generation of DAC/amp that are optimized for OTG usually have either fully self-powered USB DAC section or draw under 150mA in total in order to work with smartphone's very limited USB power supply. Older DAC/amp however are designed with PC in mind and thus draw too much power from the smartphone - which either trigger a warning on over-drawing power on the smartphone itself or the smartphone simply fails to power up the USB DAC section completely,
 
It can probably be done if you connect the smartphone to a self-powered USB hub first, then the USB hub to the USB DAC. Then again, not really portable anymore.

 

[drummerdimitri]

I just measured the current draw from the USB port to be 20 mA  from both the computer and the phone so it's definitely not a power issue.
 
What else could be the problem here? I'm guessing the implementation of the DAC is different in the RSA than the dragonfly.
 
Any ideas?

 

[drummerdimitri]

Never mind. I read an article and turns out it was just the software.
 
I downloaded a USB player for my phone and now detects the DAC and plays music through it!
 
All solved with 10 bucks