Exploring the Aurender ACS100 CD-Ripping Process

April 10th, 2021
By: Carlin "Rick" Smith

Background

It's been a while since I have written a new article but decided to sit down and share my thoughts on how Aurender digital transports capable of CD-Ripping work. This would include as of date of this article three models - A30, ACS10, and ACS100. For this evaluation I chose the relatively inexpensive ACS100 to study the process. This article does not cover playback of music with the ACS100. The ACS100 is certainly capable of that and most would use it as a streamer/ripper/music player. My goal was to study two aspects of the ACS10/ACS100 as part of Aurender ecosystem. The first is to perform all ripping strictly with the Aurender versus utilizing a computer for ripping. The second is to pair the ACS100 with another Aurender, in this case a W20SE, as additional storage for that unit.

If you are coming across this article, you might ask yourself your expectations of metadata of your music library. If you are the type that just plays music and could care less about uniformity or consistency of your album metadata like genres, covers, and naming conventions, to name a few, then I can short circuit the article and say the Aurender system could absolutely replace a computer for ingesting your CDs in lossless audio. If you are the type at an audio show that picks up an iPad to pick a song to demo and it feels like you just pulled into the local salvage yard to try and find something, then read on as the answer is more nuanced. I definitely fit the latter category and have spent literally thousands of hours curating my own 100,000+ song library over two decades. These are not right and wrong categories, not chocolate or vanilla, each person will ultimately do what works for them.

Enough setting up the experiment lets dive in.

About the Aurender ACS100

The ACS100 was developed to be a more cost-effective version of the ACS10 offering many of the same functions as the ACS10.

As a music server / streamer, the ACS100 enjoys operational control via Aurender Conductor for both iPad/iPhones and Android devices. All the features you’d expect from Aurender like clutter-free direct access to your music as well as app-embedded Tidal and Qobuz subscription streaming services, Spotify Connect, internet radio, MQA Core decoding (optional), CD ripping and advanced metadata editing and library management.

Storage

ACS100 provides two sliding trays located on the rear panel that are designed to hold your choice of HDDs or SSDs for storage. You can install one drive to start and as your storage requirements change, add another or load both for maximum storage capacity.

CD Ripping

Aurender’s CD ripping engine creates the best sounding files in your choice of FLAC, WAV or AIFF codecs. Metadata is automatically retrieved, and the album cover art and other metadata can be viewed on the front panel display. A TEAC CD-ROM drive extracts the CD data in bit-perfect fashion in a one-touch operation and places the file in a user determined folder for immediate playback.

Tag Editing and Library Management

Smart Tag Editor is an application for the modification of various metadata fields allowing user to correct the files tags to suit their music sorting requirements. A Copy / Move / Delete feature allows for easy transfer of music libraries from various other network attached devices and can also perform a scan for duplicate file removal.

Aurender Ecosystem

One can use the ACS100 as a central server for other Aurender players. Connectivity is accomplished over the network allowing the ACS100 to be placed anywhere convenient. Although the ACS100 can operate as a stand-alone music server / streamer, best sound quality is achieved when using an N100H, N100C, N100SC, N10, A100, A10, A30 or W20SE Aurender music server / streamer as the main player.

I/O Ports

A USB Digital Audio Class 2.0 output allows ACS100 to function as a music server / streamer when connected to an external DAC. Two USB 3.0 data ports (one on the front panel, one on the rear) allow for fast data transfer to the ACS100’s internal drives. Another USB 2.0 located on the rear panel can be used for thumb or USB storage devices or for connecting to a Acronova Nimbie AutoLoader (optional – third party supplied). An isolated LAN port is provided for direct connection to your router.

Power Supply with Integrated UPS

A 19V power supply adapter plus a “super capacitor” based uninterruptible power supply (UPS) for stabilizing the ACS100 under an abrupt power outage condition.

I installed a Western Digital Blue 2TB SSD in the ACS100 for this test.

My Normal Ripping Process

While it is becoming an increasingly less frequent activity these days my typical workflow for ripping a CD is the following:

Let's dive into these steps and why I use them.

Ripping a CD from a physical drive I use dBpoweramp. This is a mature application available on both Windows and macOS and is extensively configurable. As an example, I prefer my filenames closely resemble the track title and it is easy to configure dBpoweramp to conform to my chosen naming convention. I also ensure before ripping that metadata including covers meet my expectations. There is another more important feature which is the ability to check the quality of your rips against known good rips through integration with AccurateRip. There are other rippers that use AccurateRip and although not advertised the ACS100 uses it as well - more on this later. More information about dBpoweramp is available here.
If need to make other post-rip adjustments I use Yate. Since my Aurender represents a copy of my library where the master copy is stored off-line for backups (including DR copies in the cloud) I will often use other tags like GROUPING, STYLE, Comment and a few others. Conductor doesn't use any of these, but it gives me a way to look at the library in other dimensions on the computer. Predominately I use Yate when purchasing digital music downloads in which case steps 1 & 2 are inverted and as opposed to the ripping function of dBpoweramp I use the converter just to readjust all files names to my standard. Yate is an incredibly powerful application, but the learning curve can be somewhat steep to utilize the automation features. More information about Yate is available here.
The next two steps are about quality assurance of the files. In step three I use PerfectTUNES which looks at your library from a macro perspective and can identify inconsistences in the metadata. For example, if an artist's name is spelled different on two different albums or has an inconsistent case. It also communicates with AccurateRip so if you have never scanned your CD lossless files it's a good way to get a view of the quality of the rips. More information about PerfectTUNES is available here.
Step four I use a free program called Audio File Health Check from the same company, 2ManyRobots, that produces Yate. This application looks at the structure of the metadata itself and can identify errors like multiple tags, etc. The first time I ever used this program I was surprised at the number of these small issues throughout my library. While this program is free if you want to automatically fix anything logged you do need Yate which reads the logs and will fix the majority of errors in a batch process. More information about Audio File Health Check is available here.
The final step is to synchronize the changes of the master library to the Aurender itself. I use Chronosync mainly because of its excellent configurability and the inherit knowledge of macOS, Finder tags, UNIX file permissions, and to chain together multiple sync operations in a batch. This is helpful when you Aurender contains more than one disk, or you have more than one Aurender in your ecosystem as I did in this evaluation and files are distributed amongst them. Chronosync also allows for pre and post sync operations and I have scripts that remove extra files and attributes from the music library before files are copied to the Aurender. The Aurender safely ignores these extra bits but I like knowing the library is clean. More information about Chronosync is available here.

There are many good applications that exist on Windows and macOS. This is set of applications I have landed on after much experimentation through the years.

This is a carefully crafted process based on two decades of experience with digital music files. Almost every time I think it can't be improved any more, I learn something new, and I have probably been through my entire library or portions hundreds of times with bulk batch operations. It normally starts with some hypothesis like do any of my files have more than one cover embedded, or do I have any legacy iTunes specific tags from early days either ripping with iTunes or manipulating the library with it? The applications in my toolbox allow me to test the hypothesis and if true fix it in bulk across 100K files.

Taking the plunge of not doing any of these steps on the computer and instead using the ACS100 for rips and ACS Manager on the iPad for metadata management was a big one. Let's explore how things changed during this evaluation.

ACS100 Ripping Process

The ACS Manager home page depicted below now becomes your single interface to your metadata.

In a much more simplified approach, you place a CD in the ACS100 slot drive and ripping will begin automatically. The picture below shows the default factory options. Also note that the RIPs are stored on a drive you have previously inserted and formatted. There are relatively few options.

Under tag editing the number of options is even more limited.

In the ACS Manager you can see the status of your current rip and history. Along the bottom of the application screen are the options available to adjust Artist, Album Artist, Album Name, Track Titles, Album Art (Cover, Back, Liner), Genre, Year, and Composer. Conductor doesn't use any other metadata, so it makes sense when ripping on the ACS100 the only editable tags are the ones the player uses.

Once the rip is finished you can use the ACS Manager File Utility to move the music around on either the local unit or you can copy/move files to Aurender players connected to the ACS100. In this screen shot an Aurender N100 is attached to the ACS100 and you can move files between units and various drives.

After ripping completes the music is integrated into the Conductor music library for playback. On the playback Aurenders you can configure the ability for each Aurender to have it owns music library or have a single aggregated library on the Aurenders used for playback. Each ACS10 or ACS100 can support ten connected Aurenders. For my evaluation I chose the combined Conductor database being on a W20SE that showed music from both the local drive in the W20SE and the drive in the ACS100. This feature is pretty cool if you have a large library that won't physically fit on a single Aurender and want extra space without having to purchase and configure a NAS solution. If you have a multi-room listening environment it also allows for the music to be centralized.

The final step three is more a recommendation than a necessary step which is to backup your Aurender since it is now the single source of truth.

Simple, easy, it works, and requires no computer. However, I want to dig deeper.

More About ACS100 Ripping Process and Editing

I wanted to understand more what was happening behind the scenes. I connected to the Aurender remotely to inspect the ripped files.

Starting with the album Discovery from Daft Punk below is a screen shot of the resultant files I copied off the ACS100.

Key points:

You notice this album has both the cover and backcover art
The cover artwork is 1000x1000 pixels while the backcover is only 300x300
Files are reasonably named
Default folder name is Album Year - Album Title
There are three other files .accurip, .log, and .out which are the ones I want to examine

Starting with Discovery.log unveils that under the cover the ACS100 is using the open source CUETools application and specifically the CUERipper component.

CUERipper v2.1.6 Copyright (C) 2008-13 Grigory Chudov

EAC extraction logfile from 30. October 2020, 17:59

Daft Punk / Discovery

Used drive : TEAC CD-SN250 Adapter: 1 ID: 0

Read mode : Burst
Utilize accurate stream : Yes
Defeat audio cache : Yes
Make use of C2 pointers : No

Read offset correction : 0
Overread into Lead-In and Lead-Out : No
Fill up missing offset samples with silence : Yes
Delete leading and trailing silent blocks : No
Null samples used in CRC calculations : Yes
Used interface : Native Win32 interface for Win NT & 2000
Gap handling : Not detected, thus appended to previous track

Used output format : Internal WAV Routines
Sample format : 44.100 Hz; 16 Bit; Stereo

TOC of the extracted CD

Track | Start | Length | Start sector | End sector

---------------------------------------------------------
1 | 0:00.32 | 5:20.63 | 32 | 24094
2 | 5:21.20 | 3:27.40 | 24095 | 39659
3 | 8:48.60 | 4:58.25 | 39660 | 62034
4 | 13:47.10 | 3:44.22 | 62035 | 78856
5 | 17:31.32 | 3:31.48 | 78857 | 94729
6 | 21:03.05 | 1:44.35 | 94730 | 102564
7 | 22:47.40 | 3:57.60 | 102565 | 120399
8 | 26:45.25 | 3:21.60 | 120400 | 135534
9 | 30:07.10 | 3:51.05 | 135535 | 152864
10 | 33:58.15 | 3:47.65 | 152865 | 169954
11 | 37:46.05 | 5:44.67 | 169955 | 195821
12 | 43:30.72 | 3:26.65 | 195822 | 211336
13 | 46:57.62 | 4:00.13 | 211337 | 229349
14 | 50:58.00 | 10:00.22 | 229350 | 274371

Track 1

Filename /tmp/Ripping/Daft Punk/2001 - Discovery/01. One More Time.wav

Pre-gap length 0:00:02.42
Peak level 100.0 %
Track quality 100 %
Track progress 100 %
Copy CRC 3E5C754E
Cannot be verified as accurate (confidence 1458) [FBEC24D3], AccurateRip returned [1DCA4E34]
Copy OK

.........

Track 14

Filename /tmp/Ripping/Daft Punk/2001 - Discovery/14. Too Long.wav

Peak level 100.0 %
Track quality 100 %
Track progress 100 %
Copy CRC A51BA676
Cannot be verified as accurate (confidence 1441) [C81B055D], AccurateRip returned [04F5282B]
Copy OK

No tracks could be verified as accurate
You may have a different pressing from the one(s) in the database

No errors occurred

End of status report

CUETools supports MusicBrainz and freeDB metadata databases. This is a solid choice given a mature application and one that also utilizes AccurateRip. However, there is nothing on the ACS100 display or the ACS Manager UI to notify the user that a rip is considered good or if any errors exist. Your only choice if you want to know this detailed information is connect via a computer and examine the files. If you do this, you fundamentally break one of the value props of the ACS100 which is to avoid using the computer.

The other observation from this log file is that the tracks appear to be ripped in WAV format regardless of the ACS Manager setting chosen. In my case converted to my preference of FLAC.

This Discovery.out excerpt seems to confirm this conversation after ripping.

REM DISCID AF0E4A0E
PERFORMER "Daft Punk"
TITLE "Discovery"
CATALOG 0724354278228
REM DATE 2001
REM DISCNUMBER 1
REM TOTALDISCS 1
REM COMMENT "ACSRipper Copyright 2018, Aurender Inc."
FILE "00. (HTOA).flac" WAVE
TRACK 01 AUDIO
PERFORMER "Daft Punk"
TITLE "One More Time"
INDEX 00 00:00:00
FILE "01. One More Time.flac" WAVE
INDEX 01 00:00:00
FILE "02. Aerodynamic.flac" WAVE
TRACK 02 AUDIO
PERFORMER "Daft Punk"
TITLE "Aerodynamic"

The last observation is that CUETools is a Win32 application. My initial reaction was - uh what? - since the Aurenders run Linux not Windows. This must mean that a Linux compatible program like Wine is being used to emulate Windows. From examination of the CUETools Wiki page I found the following:

Users report they have been able to use it under Linux, using

Mono, but in this scenario only WAV audio is supported, as other codecs are not yet ported to C#.

Wine, using Winetricks or PlayOnLinux to install the .NET Framework and Visual C++ 2008 runtime files in a wineprefix.

Perhaps Mono is being used to run CUETools on Aurender's Linux distribution and is why all files are ripped to WAV first then converted to either FLAC or AIFF based on user preference in the ACS Manager. I have not confirmed this with Aurender, but the evidence supports the hypothesis.

The last file Discovery.accurip is the output of the comparison of tracks to the AccurateRip database.

Below is an excerpt of this accurip log file from the album When The Pawn by Fiona Apple. This particular disc has a known issue on track 3.

[CUETools log; Date: 10/30/2020 4:48:25 PM; Version: 2.1.6]
[CTDB TOCID: 0N3KZOaor0jBX18V5Ccx.Uei838-] found.
[ CTDBID ] Status
[7d1f703f] (22/22) Differs in 22 samples @10:30:43,10:38:41,10:44:26,10:49:04,10:52:74,10:53:11,11:03:52
Track | CTDB Status
1 | (22/22) Accurately ripped
2 | (22/22) Accurately ripped
3 | (22/22) Differs in 22 samples @01:26:28,01:34:26,01:40:11,01:44:64,01:48:59,01:48:71,01:59:37
4 | (22/22) Accurately ripped
5 | (22/22) Accurately ripped
6 | (22/22) Accurately ripped
7 | (22/22) Accurately ripped
8 | (22/22) Accurately ripped
9 | (22/22) Accurately ripped
10 | (22/22) Accurately ripped

Compare to same CD during ripping in dBpoweramp on computer below and you can see same issue with track 3.

Below shows a PerfectTUNES check of the files copied off the ACS100.

Lastly there are some UD (User defined) tags written to the files by CUERipper. An example in the below screenshot.

One More Thing....

I decided to spend some time making random edits to the metadata of about twenty ripped albums. The interface was reasonable if not a little unrefined compared to the relative maturity of the Conductor application. After making the changes with ACS Manager the metadata would update in the Conductor interface relatively quickly so all good.

But then I noticed something very peculiar which is that the information in Conductor indeed reflected my changes but the time stamps on the music files themselves were not changing. How could this be when I know the metadata was changing. I transferred a few of the rips back to the computer and they had the old metadata not the changes I made. My conclusion is that post rip ACS Manager simply updates the metadata that Conductor uses and does not write the changes to the files themselves. I personally find this an odd design decision and the only real positive I could muster is that it doesn't require scanning or re-writing files. I also speculate the reason this occurs is that the ripping process relies on a 3rd party open-source tool and additional manipulation of the music files is just not part of the Aurender applications at the moment. The only choice is to update the Conductor database until such time as they gain such capability. The negatives of this approach are many. My biggest gripe is that a copy of the files off the Aurender is now not a perfect copy and the ability to restore these metadata changes are in question if you had to replace a failed Aurender. I have written an extensive article about the Aurender backup/restore process and I don't believe this metadata is in that backup.

Conclusion

This was very interesting technical evaluation over sixty days, and I will summarize my conclusions.

Positives

Aurender ACS100 has three main features in one chassis - music streamer, CD Ripper, and centralized storage for other Aurender players
The ACS Manager is capable of accurate rips with a proven ripping tool
The ACS Manager can edit the limited number of tags that the Conductor currently uses
A non-technical user or a person that just doesn't want to deal with computer based ripping can easily live in this environment
Existing music on an Aurender from other sources can be edited with ACS Manager
Integration with additional playback Aurenders is very nice feature

Improvement Areas

The ACS Manager application while functional definitely feels like a "1.0" application but I am sure will mature over time
A setting to edit metadata before ripping starts
Aurender needs to address the ability to backup metadata through Aurender backups or writing tags to files themselves
Aurender should show the user a summarized accuracy reports after rips in the ACS Manager

At the end of the day the ACS100 doesn't fulfill my personal needs for metadata manipulation but to be honest I never expected it to or think that it should. I found myself after learning how the process works would utilize the ACS100 to do the rip and then immediately transfer files to computer for further manipulation. I have no issue doing this and the other uses of the ACS100 in conjunction with my primary Aurender were solid. The ACS100 also gives you a 2nd player if anything happens to your primary.

Revised Process Using ACS100

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