How relevant is PA's sound quality?

[drftr]

Hi all,

 

I'm planning to move away from my iPod and start using a Galaxy A52 with the recent Sony WF-1000MX4 Bluetooth in-ear headphones. If I understand things correctly, no matter how good or bad the music app sounds, it won't have an effect on the sound quality I will witness, as the Sony (or any Bluetooth headphones really) has it's own DAC. On top of that Bluetooth 5.0 has it's own restrictions for any signal passing through.

 

My questions are whether my assumptions are correct, and whether Poweramp possibly changes any part of the signal in the digital domain as to provide a "better" source signal to the headphones' DAC.

 

Your thoughts are appreciated...

 

drftr

[drftr]

Nobody knows? Can't be true when talking about audiophiles' favourite app, right?

 

I do know there's a lot of confusion about this subject though from checking the web. But that's exactly why I would like to double check with (f)actual users (and developers of course!).

 

Tnx...

 

drftr

[MotleyG]

Kind of a subjective question. But given that you are asking about SQ and listening to Bluetooth headphones, there is already going to be compromised sound issues. This may or may not be the weakest link in the chain in my opinion, but you also have to consider the source files, the playback device, and others. The app is of course important too, and Poweramp is one of the best sounding. But are your files sourced from high quality means like lossless hi def? Does your device support hi res files and have a decent DAC and amplifier? Are your headphones able to deliver hi definition?

So many questions, the app itself is just one component in the chain.

[maxmp]

@drftr Poweramp changes sound if you command it to do so. It doesn't change anything if equalizer/tone (and other knobs) sit on zero. Poweramp v3 has a bit more accurate decoders/audio engine in terms added quantization noise for the compressed formats (no intermediate fixed point 16 bit conversion as most other players do) and few other techniques such as wide intermediate 64 bit format for DSP, but this is not possible to hear and very hard to measure things.

[drftr]

Thanks all...

 

Since the signal that is received by the Sony WF-1000XM4 is digital (it has to be for going through Bluetooth) and gets converted in its internal DAC, I take it any change in the analog domain on the phone is ignored / bypassed, and the headphones completely interprets the source file itselves. I think this simply HAS to be the case UNLESS Poweramp is not (or not only) changing the analog signal that can be picked up directly through the phone's speakers or analog headphones, but also changing the DIGITAL signal so that the changed signal is picked up by Bluetooth and seen as the new original "source file" by the Bluetooth headphones. If that is the case then I think there's only 2 possibilities:

 

1. Poweramp is somehow able able to change files in the digital domain;

2. Poweramp uses a DAC, then changes sound, etcetera, and then uses a ADC to convert it back to digital again.

 

Since both options seem to be very "expensive" (technology, power consumption, etc) my expectation is that there is another option:

 

3. In the case there is a DAC AFTER the digital signal leaves the phone that is used by an external headphones (or whatever), Poweramp's sound modifications are ignored / bypassed and the only functionality that can be used are related to the music player itself.

 

Funny thing is that when checking so called audiophile forums you can find that option 3 is the only option possible but ALSO the exact contrary. For that reason I'm reaching out to you guys to find out what is really happening, because I take it a digital signal can't be changed in the analog domain.

 

drftr

[andrewilley]

4 hours ago, drftr said:

2. Poweramp uses a DAC, then changes sound, etcetera, and then uses a ADC to convert it back to digital again.

The path stays digital right until it gets to the point where the output device needs to create actual waveforms to be amplified and sent to your ears. There is no analogue audio processing technology in a phone until it hits the phone's DAC for the audio amp output stage (for the internal speaker or wired headphones).

So for Bluetooth, the original compressed audio file is converted to an uncompressed digital audio stream, and then any required manipulation (EQ, gain, frequency, etc) is done purely in the digital domain. That data is then passed via the Bluetooth transmitter using its own digital transmission format (which may well be lossy in itself, and potentially require other sampling rate and bit depth changes) and only finally ever converted back to an analogue signal inside the headphones to create the sound waves that your ears hear.  

Andre  

[drftr]

Thanks for the excellent answer, André!

 

drftr