Standalone Audiophile Quality Music Library Player

A Music Player – Hardware or software that plays audio files. These are called digital media players which are often portable devices. Most people listen via headphones. However, when it comes to audiophiles, they wish to listen to their music through high quality sound systems. I am such a person. I originally listened to recordings in analog form on vinyl LPs. It was the late 80s when I discovered digitally recorded music. But I was apprehensive about the digital sound.

A Music Library – Hardware or software library with individual albums/tracks automatically accessible. It was in 1997 when I finally broke down and purchased my first CD player. I grew to like the convenience of easily accessing and playing recorded music. I still have this commercial grade CD player – one of the first jukebox systems that holds 300 CDs. Subsequently in 2002, I did rip (copy) my collection of over 900 CDs to lossless files on disk. I ended up storing them on a large PC I called my Music Jukebox, which I never really used all that much. I continued to use the above multi-disc player. I have since been looking for a dedicated high fidelity music player. I’ve tried a number of solutions including using my TV room PC as such a device.

In 2010, I wrote a script that converted the raw WAV files to FLAC files which I put on my modified iPod. I then used it on a docking station as a player. However, this little thing was meant to be portable not a stationary device. There were a bunch of problems including over charging batteries, screen being too small, and its connector was a bit fragile while being attached onto the docking base.

Every music player software I looked at involved a full-fledged OS instead of being an embedded solution. This included Volumio. Then upon watching a Hans Beekhuyzen YouTube video, I decided to try out RuneAudio. The problems I encountered were that I had difficulties while trying to install it. I put it off and decided to try Volumio. This did work for me, but I had to use my phone with an app to control it. Then one day, it stopped working. I didn’t do anything about it for almost a year. I had gone back to the iPod. Finally, the iPod’s docking station died … again.

I then had to hunt down an HDMI monitor so as to diagnose the Volumio player. It turned out the SD card became corrupted. So, I downloaded a newer version of Volumio. In the process, I lost all of my settings. The music was on an external hard drive so it was OK. After I got Volumio to work again, I decided I wanted a console physically attached to the Pi. I found in my stash of stuff a 9” HDMI touchscreen monitor. I enabled HDMI and rebooted Volumio. It took over three minutes to fully boot up. Without HDMI, it only took a little over a minute to boot. I decided to relegate this Volumio device to the living room.

I had a Raspberry Pi case with a 7” touchscreen mounted in it. I was going to use this for another project which was to control a piece of machinery. I wanted to see if Rune would work for me. So, I used the Volumio RPi 3B and the DAC and I temporarily installed them in the case. I figured out from various forums how to download a stable version of RuneAudio and I burned the ISO image onto an SD card.

RuneAudio came up surprisingly fast – in less than 30 seconds. Also, it was easy to locate the hard drive where the music was stored. Unlike Volumio, I didn’t have to drill down through several layers to get to the music directories every time I wanted to make another play list or play a track. Also, Rune is really fast at loading play lists. And it shuts down very quickly, about 10 seconds.

Note.  These Raspberry Pi players must do an orderly shutdown, meaning the user selects shutdown from the Menu.  If the power is suddenly turned off, unpredictable results may occur such as corrupting the SD card or SSD.

  

The Build

I rooted around in my stash of stuff and found another unused RPi 3B. I then bought another Hifiberry DAC+ Pro. I did return the original Pi and DAC to the Volumio box. I then built the following player.

RuneAudio Embedded Raspberry Pi Music Player

RuneAudio homepage says: …it is capable of being the heart of a high fidelity digital music system. As a streaming player, it can reproduce a digital music library from local USB drives or network mounts (network access storage or NAS), and it can also play any internet stream such as web radio.

As a digital player, RuneAudio is at the top of the audio signal flow chain. It offers perfect and gapless playback of most common audio formats. RuneAudio works best when the Pi hardware is connected to an asynchronous USB 2.0 DAC, an I2S bus DAC, or an S/PDIF output to a DAC.

RuneAudio can be either a headed player or a headless Wi-Fi player. It can either be remotely controlled by multiple web browser clients running on different devices or via an optionally attached touchscreen as shown above. No installed mobile apps necessary.


Hifiberry DAC+ Pro

Specs

  • Maximum output voltage 2.1Vrms
  • DAC signal-to-noise ratio 112db typical
  • DAC THD+N -93db typical
  • Frequency response 10Hz-90kHz (-3dB)
  • Input gain -12db to 32dB
  • Power consumption <0.3W
  • Sample rates 44.1-192kHz

Audio data shaping is unaffected by the software insuring that the lossless source data is sent in its entirety directly to the DAC. Meaning, all the player does is read the data, decode it and send that data to the DAC. It is the DAC that is responsible for accurately and faithfully reproducing the music. Also if one were to choose to enable volume controlling, the volume control is done by the DAC via commands sent from RuneAudio.

Software volume control is a method of using the player software to computationally modify a digital audio data stream to decrease the playback volume by calculating a lower amplitude for each sample.

Hardware volume control is a volume control the hardware DAC board provides. RuneAudio sends the unmodified data to the DAC that handles the volume control internally. RuneAudio just sends a message to the board like “set the volume to 67%.”  Note. This method is also a computational methodology performed by the DAC similar to a software volume control. This is different from the volume control on an amplifier, which is an analog method of attenuating (decreasing) the signal being passed from the preamplifier section to the power amplifier section of an amplifier.

I disabled the volume control. I use the handy volume control on the amp. On the Volumio system, I use a remote control fob which mechanically rotates an analog volume control.


Hifiberry DAC+ Pro on Raspberry Pi 3B+

DAC Attributes

  • Dedicated 192kHz/24bit high-quality Burr-Brown DAC.
  • Gold-plated RCA jacks.
  • Hardware volume control. You can control the output volume using RuneAudio or any application that supports ALSA mixer controls.
  • Connects directly to the Raspberry Pi. Plugs onto Raspberry Pi conforming to hardware-attached-on-top (HAT) specification.
  • Compatible with Raspberry Pi models A+, B+, and 2B.
  • Directly powered from the Raspberry Pi or by additional linear power supply making the DAC completely independent from the noisy Raspberry Pi switching power supply.
  • Ultra-low-noise voltage regulator.
  • Two ultra-low jitter clock generators (22.5792 MHz and 24.576 MHz) make the DAC independent from the Raspberry Pi clock.

   

The Case

 

SmartiPi Touch Pro Case for Raspberry Pi 7" Touchscreen Display – Large sized (deep shell). The Raspberry Pi with the mounted Hifiberry hat with the RCA audio sockets protrudes too far to the back for the small (shallow shell) case.


RuneAudio Player Back

Music data is stored in WAV file format on a 1TB 2.5 inch SSD in an enclosure which is attached with Velcro to the back of the case.

The disc’s parent directory is divided up into Genera, subdivided by album and then by tracks. There are some folders that are album compilations such as the Beetles, Deep Purple, A Jazz Night Out with Verve and multi-disc albums including the Toscanini RCA Collection.

Note. The RCA plugs had to be rather stubby to fit within the tapered back of the case.

For faster track search and selection, one should use a Raspberry Pi 3b. A power hungry RPi 4 would be overkill and is not really necessary.


Raspberry Pi 7 inch Touchscreen Display

  

The Power Supply

The power supply I used is a NOS linear 3A regulated 5V supply. These non-switching supplies are readily available on eBay.

Instead of adding a second power supply for the Hifiberry, a filter circuit was constructed. The resistor reduces the fan load and its speed. RuneAudio doesn’t tax the Pi’s processor so it runs rather cool. The resulting 5V output to the DAC is very clean DC.

  

The Volumio Player


Volumio Music Player

As I said before, I did build a Volumio music server with a Raspverry Pi 3B and Hifiberry DAC+ Pro. On this setup, I obtained a steel case that held both the Pi and DAC. I eventually used an external monitor and a dual 5v supply. I added a barrel jack to the case for the DAC’s filtered 5 volt supply.

  VS   

In my comparison of these two players, I prefer RuneAudio. For what I use these platforms for, I like the simplicity of Rune. As for audio quality, it doesn’t matter which platform is used. It is the DAC that determines the audio quality. I also wanted a touchscreen attached to the Pi. The problem with Volumio is, it is extremely slow in coming up with a touchscreen monitor connected. As for RuneAudio, it takes only about 15 seconds to fully come up and start playing music. It seems Volumio is designed for smart phones. Also, it is said to be feature rich and is what the modernist would very much like – such as streaming. However, most external streams are of a substandard audio quality.

Finally, the cost. RuneAudio is free and is supported by kind donations. Whereas Volumio… Though its basic functions are free, the advanced features require a monthly subscription.

The final thought about the two systems: They both require file metadata to allow them to display genera, track number, album title, song title, etc. The problem is, I have wave files. WAV files don’t support metadata. Within Winamp, there was a kind of scripting language that allowed it to read and parse the folder/file names to obtain this metadata information which was encoded in the folder, subfolder, and file names.

Classical
    Bach - Goldberg Variations
        01 - Glenn Gould – J.S. Bach- Goldberg Variations – 1. Aria
        02 - Glenn Gould – J.S. Bach- Goldberg Variations – 2. Variation 1
        …

Rock
    Deep Purple
        Deep Purple – Machine Head
           01 – Deep Purple – Highway Star
           02 – Deep Purple – Maybe I'm A Leo
           …
       Deep Purple - Machine Head (Roger Glover Remixes)
          01 – Deep Purple – Highway Star
          02 – Deep Purple – Maybe I'm a Leo
          …

Genera
    Compilations
        Composer/performer – album title
           Track – Artist – Title – Subtitle

The separator is “blank hyphen blank” a blank, a dash and a blank. “J.S. Bach- Goldberg Variations” is treated as one title because there’s no blank before the hyphen.

As you can see, all the metadata is there. It’s just that both Volumio and RuneAudio can’t parse out the information.

So many people today want all kinds of accessibility to allow them to listen to and download their entertainment. As I’ve said in The New Audio Fidelity, most of the stuff available is compression-based and in no way measures up to audiophile standards. Also, every track I have in digital form is on a corresponding legally obtained archival grade CD or LP. No bootleg stuff.

Aw yes, Winamp, the holy grail of music players.

Out of the box: everything’s at your fingertips – on one screen – not feasible with today’s smart phones. Well, not fingertips; rather, a mouse pointer.

It seems everything has been dumbed down for these relatively tiny mobile devices. We sacrificed so much for portability. I guess it’s because so many of us no longer stay at home and are on the road for so many hours a day. So, I guess we have to be into portability.

The new owners of Winamp keep claiming they are – rebuilding Winamp for the next-generation. Not just updated, but totally remastered. The new Winamp connects you to your music wherever you are. It brings you closer to the artists you love. It’s home to your favorite music podcasts and radio stations.

Meaning, it’s not going to be the same Winamp.

S December 4, 2021