Why is CD transport still being used?

[boxerfan88]

Digital files (WAV, FLAC, AIFF, etc...) is generally acknowledged as an error free method to store digital music (16b/44k1 etc..).

Why is it some audiophile still like to use CD transport which can be error prone due to dirt/scratches/etc... ?

Does these error help make CD sound better than digital files ?

Each frame contains a total of 588 channel bits with the following break-down:

• sync pattern 24+3
• control & display 1*(14+3)
• error correction 8*(14+3)
• user data (or application data) 24*(14+3)
• Frame Total 588 bits

Sequence: Sync + Control & Display + 12 Data + 4 Error Handling + 12 Data + 4 Error handling

Error Handling:

• The goal of error handling on a CD-DA is the detection and correction of typical error patterns. An error is usually the result of scratches or dirt.
• The first level of error handling implements two-stage error correction according to the Reed-Solomon algorithm. For every 24 audio bytes, there are two groups of correction data bytes, each of four bytes.
• The first group corrects single-byte errors while the second group corrects double-byte errors.
• In the second level, real consecutive data bytes (24 bytes) are distributed over multiple frames. The audio data are stored interleaved on the CD-DA. In this way, burst errors will always damage only parts of the data.
• An error rate of 10-8 is achieved.

encl:

 

[ml]

I will hazard a guess in response to your question / topic…..(getting ready anti-flame suit)….

Decisions on choosing what way to playback digital files:

How are the digital info stored? CDs, or in SSD or even HDD? Or no storage device (solely dependent on subscription service to service provider, therefore no choice on individual level what music he or she can keep in possession)?


How durable is the storage device or medium (SSD etc vs CD), chances of data loss / leak / corruption over time, and what ways to correct / remedy this ?

Costs involved (over how many years)?

Sound quality comparison? It is not merely accuracy of 1s and 0s, but also the accompanying power supply / noise / software or hardware etc of the device concerned…..

Convenience (in procurement, setting up, storage, playback, etc)?

Past history / experiences in the hobby? Perhaps the hobbyist already has huge collection of CDs to begin with, before streaming / computer audio comes into being?


Hi boxerfan88, have you compared side by side between a cd transport / cd player against a device playing back digital music in another way? What are your opinions regarding the respective sound qualities?

 

[boxerfan88]

Hi boxerfan88, have you compared side by side between a cd transport / cd player against a device playing back digital music in another way? What are your opinions regarding the respective sound qualities?

Just over 10 years back when I began re-ripping my CDs to FLAC, I did compare the two. I couldn’t tell them apart. That’s why I went full on to rip all my CDs into FLAC.

My CDs are all now in boxes. My CDP is also stored away.

 

[boxerfan88]

Additionally, for some HiFi visits this year, I cut into CD-R (CDDA) some of my favourite (FLAC) test tracks to bring along coz the host didn’t have streaming.

The self-made CD-R sounded the same as the FLAC files when I tested the CD-R on my own system (to confirm the CD-R is created properly).

 

[ml]

Some people do find some differences in sound quality between CDs and streaming, and between SSD and HDD music etc, so there lies some of the reasons ….

 

[boxerfan88]

I would split digital music to 3 categories:

1. CD
2. CD rip
3. Streaming

From my own experience, referencing my own CD collection, I find (1) sound the same as (2).

And if I compare (2) and (3), I also do sometimes hear some differences between CD rip and Streaming on my own system.

I cannot say for certain why it is so, but my guess is:

• different mastered copy on the streaming platform, compared to my CD rip
• streaming platform enforcing loudness normalization (https://youlean.co/loudness-standards-full-comparison-table/)
  • Spotify -14LUFS, true peak -1dB
  • Tidal -14LUFS, true peak -1dB
  • Apple -16LUFS, true peak -1dB
  • Amazon -14LUFS, true peak -2dB

As I type this post, an idea came to my mind ... when I have spare time ... I should use DeltaWave to compare one of my CD rip with Streaming copy...

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[blue_starfish]

My own finding so far descending order of quality :
1. Mid-tier CDP (more engaging sound although ragged at times)
2. CD drive, direct playback via streamer (Sabre R2R chip - very smooth but robs the rawness of live recordings)
3. Stream from SSD in WAV format (very close to #2 above. Cannot tell unless A/B immediately one after another)
4. Stream from SSD in FLAC format (too polite, loss HF sparkle)

Yet To Do and critical listen :
a. Stream from TIDAL/Apple Music (results still TBD)
b. Attach my mid-tier CDP and use as a transport via 75 ohm SP/DIF co-axial cable to DAC section of streamer

 

[Bloody Chowbotak]

I have compared the following 2 combination:

1 YBA CDT450 cd transport to Chord Dave DAC
2 Naim NDX streamer as transport to Chord Dave DAC

1 has an overall brighter, slightly airer and more details
2 sounds a little less detailed, smaller soundstage but has a more engaging or should I say more musical

I suppose it all depends on what eqpt u use to compare and the other eqpt in yr setup

 

[boxerfan88]

I found a little bit of time this afternoon to do a comparison.

I selected one of my favorite CDs of all time - ABBA Gold - and choose the song "Chiquitita".
The CDrip was from the CD I bought decades ago.

Preparation

• I took my CD rip file, decoded it to WAV.
• I obtained Tidal file, and decoded it to WAV.

Listening test

• The CD version sounded a little soft yet very balanced and nice, soundstage was set a little bit back, the highs were crisp and pleasant.
• The Tidal version sounded much louder, and more "in your face" and "shouty", warmer, more bass thump, and the highs wasn't as nice.
• Conclusion: I preferred the CD version for sure.

Analysis (only done after listening test)

• FC /b comparison confirms both WAV files are different.
• A look at the file sizes show slight differences (74KB).
  • 
• A look at the waveform in Audacity ... oh gosh ... so very very different.
  • 
  • Walao eh ... somebody remastered the Tidal version, and compressed the hell out of it - look at the chopped off peaks. Siao ah..
• A look at both WAV files in DeltaWave.
  • blue = cdrip, white = tidal
  • 

Conclusion:

• From just listening, I definitely preferred my CDrip copy.
• From the analysis, we can see that the Tidal streamed copy has been remastered/loudness normalized and compressed.
• No wonder people still like CDrip/CD version.
• I am happy that differences that I heard can be explained scientifically from the analysis.

.

 

[tachyons]

Good work on the analysis. It also explains why I always find Tidal sounds louder and more boosted than Apple Music for the same song.
For streaming, local streaming is the way to go with ripped FLAC or WAV files on a NAS, or even better, an SSD directly plugged into the USB port of the streamer.

 

[Cash]

well, here's my point of view...
Tidal or Apple music or Spotify also need to get the music files ripped into their own respective streaming platform storage..
so if they get CD's or Master Tape Reels or Vinyl Records to Rip to their own storage ....
the question is.... where did they procure the music file, and "Pressed and Mastered by who"?
if u get japanese pressed cd's, its always gonna sound "Shrill"
if u get USA pressed cd's, it also isnt reallly that great.
European cd pressing is much better.
Heck, i could swear that Indonesian Pressings are the best.
the music engineer/sound man is the crucial "Player/Ears" in all of these disparity in sound perception.

 

[blue_starfish]

The difference may be even wider if you rip the CD direct to WAV. And not rip in FLAC and then convert.
Saying this only because I hear differences between direct rip to FLAC, and direct rip to WAV. With WAV being superior.

 

[boxerfan88]

Let's deep dive a little bit and take a look at the DAC itself ... using AKM AK4191EQ+AK4499EX DAC as an example.

The DAC has been split into 2 chips ... a digital processor/transcoder that feeds into a converter chip.

Let's zoom into the AK4191EQ and see what sort of signals it accepts ...

The DAC chip accepts either DSD or PCM via it's data interface.

WAV and FLAC are both not accepted by the DAC chip.

What this means is that somewhere before the DAC chip, a computer of some sort will have to decompress and extract out PCM data from either WAV container or FLAC container or AIFF container or OGG container or XXX container. Place the extracted PCM data into a buffer, and then feed it into the DAC chip for conversion to analog.

.

 

[tachyons]

Just to clarify, When I refer to a DAC in my last post, I do not mean the DAC chip alone. The DAC I refer to is the entire device responsible for converting digital signals to analog, including the power supply, digital processing circuits, analog output stages, and sometimes software for additional processing tasks.

 

[boxerfan88]

Just to clarify, When I refer to a DAC in my last post, I do not mean the DAC chip alone. The DAC I refer to is the entire device responsible for converting digital signals to analog, including the power supply, digital processing circuits, analog output stages, and sometimes software for additional processing tasks.

Yup yup.

Most box DACs take in PCM and/or DoP/DSD at their input connections, not WAV or FLAC or AIFF or OGG or DSF or DFF ...

Normally something upstream need to decompress/extract PCM and/or DSD/DoP and then pump it into the box DAC.

.

 

[boxerfan88]

In a streamer/DAC combo, this "upstream computer" is typically an ARM chip running Android/Linux and the manufacturer developed app that drives the streamer UI/UX, storage management and during playback it does the decompression/extraction of PCM and/or DSD/DoP into a buffer that is then pumped to the built-in DAC (and/or outboard DAC if supported).

.

 

[tachyons]

Paiseh, I removed my earlier post due to technical inaccuracy.

 

[Sphinx]

Some people do find some differences in sound quality between CDs and streaming, and between SSD and HDD music etc, so there lies some of the reasons ….

Hi! May I know what are the reported differences between SSD and platter HDDs? I never had the chance to do such a comparison. There are some differences between .wav files and .flac files - in certain tracks, it is clear. in others, too close to bother. for convenience and space, no real need to bother. there are also differences in the streaming options. Tidal being the least musical actually. Qobuz is preferred if available for the track desired. I find the difference between the DSD and CD versions more bothersome, with many DSDs remastered to sound worse - I presume to prove the format, they change the sound to be more hifi but failed miserably.

 

[ml]

Hi Sphinx, I myself have not dabbled in SSD or HDD, nor any streaming to begin with, so cannot relate for you any of my personal experience. However, there should be some info out there in internet pertaining to such topic, with google or other search engines being your best friend, it shouldn’t be too difficult to find at least some inputs on that….

One example:

Computer Audio – SSD versus HDD

This may be hard to believe but the type of drive also has an influence on the sound.

www.hifi-advice.com

 

[ml]

Other perspectives on SSD vs HDD:

One more time, SSD vs HDD

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