TL;DR: Is my music collection transcoded from flac to Opus under all circumstances when streaming to the Android Plex / Plexamp client?
I’ve been a Plex Pass member for a few years but not really taken advantage of it until the last few weeks. I’m in the process of encoding all my CD collection in flac. Also, I’m an Android user and plan on using Plexamp and/or Plex as my primary client.
I’m also looking to purchase new earphones/headphones and checking out different codecs. I understand that Apple devices stream so well to Apple (and other) headphones because they’re typically streaming AAC encoded files to AAC over BT, meaning there’s no conversion going on.
As an Android user I’ve typically stuck with aptX codecs for audio over BT, and recently seen some headphones that do not support aptX. I’d imagine that makes no difference to me since all my music is being transcoded from its original flac to Opus to aptX. However, is that correct? Or if I encoded everything to AAC would it stream AAC and subsequently be no codec required to transmit over BT?
There’s also the possibility that my understanding is way out I’ve tried scouring these forums and support articles but I’ve not found anything specifically relating to audio that gives me this information yet
Thanks,
Al
Server Version#: 1.23.2.4656
Player Version#: Plexamp 3.4.7
has the same number of audio channels as the original file
is allowed to use sufficient bandwidth to stream the original file
it will play the file as-is (i.e. “Direct Play”).
Flac stereo can be played “direct”, both on Android and iOS.
First thing to check is whether the device which is running the Plex client, is able to communicate with your server directly. (Verify the connection is not tagged as “indirect” in the Plex Dashboard).
Then you need to check whether the server is considering the client as being “remote”. Because for remote access, there can be different bandwidth limitations than for “local” connections.
Third is to check the defined bandwidth limitations. Settings on both the server and the client have an influence here.
4th is the cache of the clients. Plexamp in particular has a pre-cache ability, which can buffer several files at once very far in advance. If the client was remote when the file was buffered, the files in the buffer can be in OPUS format.
Even if the device moved into the local network of the server in the meantime, it will still use the pre-buffered file instead of loading the original file driectly from the server.
Plexamp has quite a few preferences to influence these mechanics.
The regular Plex apps for Android and iOS have different (and fewer) relevant preferences.
Most apps (including Plex and Plexamp) on Android and iOS are limited in which sampling rates and word depths they can use. So I’d not expect anything above 48kHz/24bit to play directly anyway.
I’ve tried scouring these forums and support articles but I’ve not found anything specifically relating to audio that gives me this information yet 
