• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required as is 20 years of participation in forums (not all true). Come here to have fun, be ready to be teased and not take online life too seriously. We now measure and review equipment for free! Click here for details.

Is there a way to turn an Android phone into a bluetooth transmitter?

Joined
Jun 21, 2019
Messages
69
Likes
55
#1
My goal here is to play video games on my laptop on the couch, but have the audio sent to my DAC with LDAC bluetooth. My computer does not support LDAC but my phone does. Is there a way to connect my phone to my laptop with USB, then have the phone stream my computer's audio over LDAC? Basically turn my phone into a bluetooth transmitter?
 
Joined
Dec 10, 2019
Messages
37
Likes
39
Location
Thunder Bay, ON
#2
INSANE SOLUTION:

I can't think of anything already made that is capable of doing this. Android phones have the capability to do this via their kernel configfs gadget drivers. You could in theory write a USB Audio Class 2.0 compliant gadget driver that when you plug your phone into a device, it is recognized as a USB audio output, and playing to it from a host, the phone could decode and route the incoming USB audio packets to a virtual ALSA input device on the phone, (on a non-rooted device you would want this to go through a few Android layers for apps to get access to) which then you could run a a simple Android app that has Bluetooth audio streaming permissions to once again forward that input to the Bluetooth audio encoder.
Yikes.
I don't think the Android team would do it for you though, lol.
Another option is for an app developer to come up with a LPCM over WiFi protocol and just write a Windows audio driver to forward over WiFi to an Android or Apple app that could send it to the Bluetooth encoder.

NOW FOR THE SANE SOLUTION:

https://www.amazon.com/Anker-Soundsync-Transmitter-Synchronization-Connection/dp/B07BR3FFTB/ ($39, maybe not the greatest reviews)
https://www.amazon.com/Bluetooth-Transmitter-Receiver-Boltune-Headphones/dp/B07V44WM9J/ ($35 with coupon applied, better reviews)
just use your laptop's optical output if it has one (usually it's the 3.5mm line out, with a glowy red coming from it)
and connect it to this!
Pair the Anker Soundsync/Boltune Transmitter with your DAC and you're good to go, sorry it's only aptX HD, but they're pretty much indistinguishable in quality most of the time
If your laptop does have a 3.5mm optical out, you will want a Toslink Mini to Toslink cable, ex. https://www.amazon.com/Toslink-Fosmon-Digital-Optical-Chromecast/dp/B01N6KZU6N/ (that was the cheapest I could find with decent reviews)

Oh, apparently you can just grab this instead: https://www.amazon.com/Avantree-Bluetooth-Transmitter-Headphones-Broadcast/dp/B07W5DDZQN/ ($39)
This simple dongle appears to support both aptX HD and aptX low latency, unlike Intel Bluetooth which only supports aptX v1 implementation.
Nice, thanks for making me research this, I'm gonna buy this myself lol!

Remember, if you are playing video games you will pretty much NEED aptX-LL. Bluetooth has latency, and aptX-LL is spec'd for under 50ms, which is still quite a bit of latency when watching movies or gaming. (realistically I'd expect around 18ms which isn't too bad)
LDAC on the other hand is not suitable for movies or gaming at all, and you can easily expect more than 120ms latency with it.

IF YOUR LAPTOP HAS AN INTEL 8000 SERIES OR NEWER WIFI CARD:

You can just pair your DAC to your PC and enable aptX audio. Honestly this is what I'd do. If your laptop doesn't, some manufacturers allow you to upgrade your WiFi cards and WiFi cards are hella cheap (like $25)
At the same time, some manufacturers are evil and have BIOS whitelists for WiFi cards and won't let you boot if you upgrade it.
 
Last edited:
Top Bottom