This reader’s mail which has just reached us first left us a bit perplexed and we have decided to process it in this column, as this situation could happen to other enthusiasts who possess the first device in question and would want to get a Qobuz streaming subscription.

Hello,

I just received the FDA FX Audio 802 amplifier, after being convinced by your review. I connected my Pioneer XDP100R audiophile digital audio player (which you also reviewed) via OTG on the amplifier’s USB input and I just noticed that Qobuz doesn’t work. And yet, the player provided with the digital audio player (the “Music” application) works perfectly.

I’m really at a loss and I don’t understand how it is possible, especially since you must have checked this type of connection with your application during your review. Therefore, I’m getting back to you to ask you if you could help me, before I send back this amplifier which will be of no use to me if your application doesn’t work via USB-OTG.

Thank you in advance for you answer.

Best regards.

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Before answering, let us remind you that a USB OTG (On-The-Go) connection between two peripheral devices compatible with OTG allows these devices to directly establish a dialog together, without needing a host computer.

With a smartphone (or a tablet) running Android connected to a DAC, the latter will automatically be handled by the smartphone (or the tablet), without any need for the user to do anything aside from authorizing the audio application when it asks to be connected to the USB DAC.

Our answer

Just like every time we receive this kind of mail, we take a look at the testing grounds of the devices in question to try to identify the problem, but here, it’s when we read the comments at the end of the Pioneer XDP-100R testing ground that an idea came to us.

- Here’s the comment which led to the idea:

Published by rono93

It would seem (according to some forums) that the ESS Sabre DAC from the XDP-100 is only used for Pioneer’s Music application. The other applications (like Qobuz, for example) don’t have access to this DAC, but only to the DAC integrated to the processor (which is equivalent to the ones present in smartphones). Are there any experts that could confirm this? Can Qobuz developers work on this?

Anyway, I’m indeed noticing a difference between music read on the stock application and the one read on the Qobuz application, and I much prefer the sound from the stock application…

- And the idea that we got from that:

Since the Music audio application installed on the Pioneer detects the connecting of an OTG DAC, why wouldn’t the USB Audio Player Pro application, which integrates Qobuz in Hi-Res and which is an audio application just like Music, also be able to do that?

And since, fortunately, we possess a Pioneer XDP-100R with USB Audio Player Pro installed on it, we proceeded to the experiment with two OTG DACs, the first (a S.M.S.L X4) being connected via an OTG micro-USB/micro-USB cable, and the second (a mDSD Encore) via an OTG micro-USB/USB A adapter allowing you to plug a standard USB cable or a USB drive-type DAC, and both worked with USB Audio Player Pro and the Qobuz application that is integrated to it. And it even worked with our Sony UDA-1 amplifier equipped with a DAC possessing a USB B input.

Therefore we think that, logically, our reader should find a solution to his problem by using USB Audio Player Pro and we would like to thank rono93 for his salutary comment.

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