My First Digital Audio Player

One of the facts which people have been aware of for several decades now, is that we can buy a portable player, specifically for MP3 files, and that if we do, the sound quality will not be so great.

But in more recent years, Digital Audio Players have emerged on the consumer market, that promise lossless playback of high-fidelity sound, the last part of which is just referred to as “High Resolution Sound” by now. This lossless playback-capability does not come, when we listen to MP3-Files with them, but rather, if we actually play back FLAC, or ALAC -Files.

I just bought This sort of device, which is a Fiio X1 II. One of the remarkable facts about this device is, that its Digital-Analog conversion can run at up to 192kHz, and it sports the possibility of 32-bit sound. What I assume in such a case is, that even if I was to listen to a 48kHz -sampled audio file, 4-factor oversampling would in fact take place, because the D/A converter would continue to run at 192kHz, and I’d also assume that the analog filter would stay as-is, with a cutoff-frequency around 20kHz. But because I am in fact listening to 44.1kHz -sampled sound, I also assume that the whole D/A converter is being slowed down to 176.4kHz. ( :1 )

I have this working with My recently-purchased headphones, and am listening to a mix of MP3, OGG and FLAC -compressed music. I would say that this combination has significantly better sound, than the sound-chip in my Samsung Galaxy S6 phone does. ( :2 )

When I received this DAP, it had firmware version 1.6 already installed. But, I updated the firmware to the latest, v1.7… In fact, formatting the SD card with ‘exFAT’, as well as applying the firmware update, worked easily for me, even from Linux computers. The SD Card is a Sony.

My only regret is, that I personally, don’t have the manual dexterity which would have been needed to install the supplied screen-protector properly. I had the presence of mind to pull it back off, when it did not align correctly, and to dispose of the screen-protector. So I can expect some scuff-marks in the future. :-)

Happy, with Music,

Dirk

(Updated 07/09/2018, 14h55 … )

Continue reading My First Digital Audio Player

Identifying the container-file-format, separately from the Codec.

One of the facts which the public is well-aware of, is that Sound and Video are usually distributed in compressed form, through the use of a ‘Codec’, which stands for ‘Compressor / Decompressor’. What may still have some people confused though, is that there is a separate distinction in file-formats, which is the ‘Container File Format‘. The latter distinction is observed, when giving the file its filename-suffix, such as .MP3, .MPEG, .MP4, .OGG, .M4A, etc..

  • An .MP3-File will contain sound, compressed with the Codec: MPEG-2, Layer III
  • An .MPEG-File will contain video and sound, compressed with the Codecs: MPEG-2 or MPEG-1, And AC3 or MPEG, Layer III Audio (Hence, ‘MP3 Audio’ is allowed.)
  • An .MP4-File will contain video and sound, compressed with the Codecs: H.264 or MPEG-4, And AAC
  • An .OGG-File will mostly contain video and / or sound, compressed with the Codecs: Theora (video) And Vorbis (sound)

Finally, because the ‘AAC’ Sound Codec, which stands for ‘Advanced Audio Codec’, has qualities which have been found desirable outside its initial usage-scenario, for movie-making, just for Audio, there has been some possible confusion, as to how the users should name a container file, which contains only AAC-compressed audio, but no video. On my Linux-computers, I’m used to giving those files the filename-suffix ‘.M4A’ . Other people may at one time have been doing the same thing. But because the suffix was not widely recognized, Apple specifically, may have just started the trend, of just naming the container files ‘.MP4-Files’ again, even though they contain no video. This may simply have helped their customers understand the file-formats better.

The AC3 and AAC sound Codecs both offer directionality in the sound, which was useful for movies, but which will exceed the degree of directionality, that ‘MP3 Audio’ offers. And so, even though AAC offers small file-sizes, it has become popular for Music as well, because the way in which the Advanced Audio Codec compresses its sound is ‘so smart’, that listeners tend to hear very high-quality sound anyway.

Dirk