Listen and choose the 8th generation digital copy.

[Blumlein 88]

Here is the frequency response after 8 generations. db scale on y-axis. Frequency on x-axis. This was caused by the ADC which has a tiny bit of ripple which is more than tiny at 800%. From about 15 khz and below the variance isn't really very large. Plus or minus a quarter db and less. I do think this is the main audible artifact. If I EQ'd that out might be impossible to hear.

One pass thru the ADC this ripple isn't above +/- .02 db until beyond 8 khz.

 

[solderdude]

I scored 0% (had them all picked wrong).
Did I suck at this or had preference ?
I compared it sighted (knew what was playing) to the reference and did not use ABX tools of any kind.
So I figure I just suck at it or the gear I tried it on (Linux Mint and UMC204HD) isn't up to snuf.

In any case the differences are too small for me to worry about, let alone with just 1 conversion.

 

[Krunok]

B

Here is the frequency response after 8 generations. db scale on y-axis. Frequency on x-axis. This was caused by the ADC which has a tiny bit of ripple which is more than tiny at 800%. From about 15 khz and below the variance isn't really very large. Plus or minus a quarter db and less. I do think this is the main audible artifact. If I EQ'd that out might be impossible to hear.

One pass thru the ADC this ripple isn't above +/- .02 db until beyond 8 khz.

View attachment 22333

If I understand correctly, this is not related to increased distortion but rather to a different refquency response, right?

 

[Blumlein 88]

B


If I understand correctly, this is not related to increased distortion but rather to a different refquency response, right?

Yep. This FR. Distortion is worst case less than -86 db third harmonic with everything else more than -100 db.

 

[pkane]

I voted on that other forum, but my score was 4/5. I got the Bob Marley one wrong. I was pretty confident about the four I got right -- each took about a minute to decide, focusing on higher frequencies. Bob Marley simply didn't have the same 'tells', and I spent quite a bit longer on it and was not at all certain about my choice, it was mostly a guess. X20pro DAC, HE560 headphones plugged into the balanced output directly, no amp.

 

[Patrick1958]

X20pro DAC, HE560 headphones plugged into the balanced output directly, no amp.

X20pro (Gustard) does not have a headphone output.

 

[pkane]

X20pro (Gustard) does not have a headphone output.

Balanced line output is what I used. This my office system, and I have no room for an amp here

 

[flipflop]

Maybe people are concerned their ticket to the audiophile playground might be revoked if they publicly admit to not being able to identify the 8th generation copies?

Quite the opposite, really. I see no theoretical reason as to why I should be able to distinguish between the samples, so I'm not really interested in trying.

 

[Krunok]

Yep. This FR. Distortion is worst case less than -86 db third harmonic with everything else more than -100 db.

When I was doing the test I was comparing A and B and when I picked one that sounded better I assumed that was the one that wasn't re-converted. Thinking again about this I came to conlucion that was the wrong technique as the one that sounds better to me doesn't really need to be the original!

 

[Patrick1958]

Balanced line output is what I used. This my office system, and I have no room for an amp here

 

[pkane]

Quite the opposite, really. I see no theoretical reason as to why I should be able to distinguish between the samples, so I'm not really interested in trying.

There is a theoretical reason: there are obvious measurable differences. Whether or not they are audible is the point of this test, IMHO.

 

[Soniclife]

the one that sounds better to me doesn't really need to be the original!

Very true, and a knowledge that will get you stoned to death in many a forum.

My opinion is it's important to differentiate between correct and preference, and know what you are choosing.

 

[TungstenC]

I couldn't discern differences between the files, had a hard time trying to do so.
*Tests were done wearing my Etymotic ER4SR with an O2+SDAC combo.

Spoiler: ABX RESULTS

foo_abx 2.0.6c report
foobar2000 v1.4.2
2019-02-23 10:04:54
File A: Bob Marley A.wav
SHA1: d3768ea41258201067946670f840a45f5f1e3a54
File B: Bob Marley B.wav
SHA1: 6dce64b387b81639b9644d8be79dd5eae90fcf17
Output:
WASAPI (event) : SDAC (SDAC), 24-bit
Crossfading: NO
10:04:54 : Test started.
10:07:44 : 00/01
10:16:05 : 00/02
10:17:41 : 00/03
10:18:26 : 01/04
10:20:13 : 02/05
10:20:32 : 03/06
10:21:03 : 04/07
10:22:01 : 05/08
10:22:40 : 06/09
10:22:53 : 06/10
10:23:32 : 06/11
10:23:32 : Test finished.
----------
Total: 6/11
p-value: 0.5 (50%)
-- signature --
500c977e2d51e51742869875e6518437ddb5065c

foo_abx 2.0.6c report
foobar2000 v1.4.2
2019-02-23 10:26:50
File A: Cowboy Junkies A.wav
SHA1: d0f0644367e8ba5d83407d438b3353a42348740c
File B: Cowboy Junkies B.wav
SHA1: 10cf5046197d55e47908412ef7bf02779b37b258
Output:
WASAPI (event) : SDAC (SDAC), 24-bit
Crossfading: NO
10:26:50 : Test started.
10:28:47 : 01/01
10:29:22 : 02/02
10:30:06 : 02/03
10:31:06 : 02/04
10:31:33 : 03/05
10:33:30 : 04/06
10:34:23 : 04/07
10:35:45 : 04/08
10:37:45 : 05/09
10:38:40 : 05/10
10:39:50 : 05/11
10:39:50 : Test finished.
----------
Total: 5/11
p-value: 0.7256 (72.56%)
-- signature --
b2b830a023d72cba7af3cfbcdd873a4b16c9ba89

foo_abx 2.0.6c report
foobar2000 v1.4.2
2019-02-23 10:41:04
File A: Jennifer Warnes A.wav
SHA1: ede63a55290916546e1b3c1e820484a640e54847
File B: Jennifer Warnes B.wav
SHA1: b2267d2dfca51d73226afb57ddb9667adbc342f5
Output:
WASAPI (event) : SDAC (SDAC), 24-bit
Crossfading: NO
10:41:04 : Test started.
10:43:26 : 01/01
10:44:32 : 01/02
10:45:26 : 02/03
10:47:23 : 03/04
10:48:05 : 03/05
10:49:11 : 03/06
10:50:05 : 04/07
10:51:42 : 04/08
10:54:21 : 05/09
10:58:27 : 05/10
10:59:28 : 06/11
10:59:28 : Test finished.
----------
Total: 6/11
p-value: 0.5 (50%)
-- signature --
3ea6533699673105f4160107d07edfb7091de4f5

foo_abx 2.0.6c report
foobar2000 v1.4.2
2019-02-23 11:01:57
File A: Phil Woods A.wav
SHA1: 05c277bc622eeacf1109f6754a23e0c859c5a379
File B: Phil Woods B.wav
SHA1: 7646a7da269e70c05d60a0056c1165ecd1f3dbdb
Output:
WASAPI (event) : SDAC (SDAC), 24-bit
Crossfading: NO
11:01:57 : Test started.
11:04:31 : 00/01
11:09:59 : 01/02
11:17:51 : 02/03
11:18:24 : 03/04
11:19:01 : 03/05
11:19:30 : 03/06
11:20:50 : 03/07
11:21:31 : 04/08
11:22:29 : 05/09
11:23:11 : 06/10
11:24:52 : 07/11
11:24:52 : Test finished.
----------
Total: 7/11
p-value: 0.2744 (27.44%)
-- signature --
256cda182eecc0726c243a7e5f0202df2a72f96f

foo_abx 2.0.6c report
foobar2000 v1.4.2
2019-02-23 11:51:39
File A: Ry Cooder and VM Bhatt A.wav
SHA1: 2b1b878c4b8a31535a43ad9037ff3b582b1fe1c2
File B: Ry Cooder and VM Bhatt B.wav
SHA1: 1833211cbc558646d94a7e40ccfbc938e42dcafd
Output:
WASAPI (event) : SDAC (SDAC), 24-bit
Crossfading: NO
11:51:39 : Test started.
11:52:22 : 00/01
11:52:36 : 01/02
11:53:13 : 02/03
11:53:28 : 02/04
11:53:39 : 02/05
11:56:00 : 02/06
11:56:26 : 02/07
11:57:52 : 03/08
11:59:03 : 04/09
11:59:25 : 04/10
12:00:05 : 05/11
12:00:05 : Test finished.
----------
Total: 5/11
p-value: 0.7256 (72.56%)
-- signature --
fe98e0260781f0c5623100fc31dae58dd7ed5847

 

[Blumlein 88]

I couldn't discern differences between the files, had a hard time trying to do so.
*Tests were done wearing my Etymotic ER4SR with an O2+SDAC combo.

Spoiler: ABX RESULTS

foo_abx 2.0.6c report
foobar2000 v1.4.2
2019-02-23 10:04:54
File A: Bob Marley A.wav
SHA1: d3768ea41258201067946670f840a45f5f1e3a54
File B: Bob Marley B.wav
SHA1: 6dce64b387b81639b9644d8be79dd5eae90fcf17
Output:
WASAPI (event) : SDAC (SDAC), 24-bit
Crossfading: NO
10:04:54 : Test started.
10:07:44 : 00/01
10:16:05 : 00/02
10:17:41 : 00/03
10:18:26 : 01/04
10:20:13 : 02/05
10:20:32 : 03/06
10:21:03 : 04/07
10:22:01 : 05/08
10:22:40 : 06/09
10:22:53 : 06/10
10:23:32 : 06/11
10:23:32 : Test finished.
----------
Total: 6/11
p-value: 0.5 (50%)
-- signature --
500c977e2d51e51742869875e6518437ddb5065c

foo_abx 2.0.6c report
foobar2000 v1.4.2
2019-02-23 10:26:50
File A: Cowboy Junkies A.wav
SHA1: d0f0644367e8ba5d83407d438b3353a42348740c
File B: Cowboy Junkies B.wav
SHA1: 10cf5046197d55e47908412ef7bf02779b37b258
Output:
WASAPI (event) : SDAC (SDAC), 24-bit
Crossfading: NO
10:26:50 : Test started.
10:28:47 : 01/01
10:29:22 : 02/02
10:30:06 : 02/03
10:31:06 : 02/04
10:31:33 : 03/05
10:33:30 : 04/06
10:34:23 : 04/07
10:35:45 : 04/08
10:37:45 : 05/09
10:38:40 : 05/10
10:39:50 : 05/11
10:39:50 : Test finished.
----------
Total: 5/11
p-value: 0.7256 (72.56%)
-- signature --
b2b830a023d72cba7af3cfbcdd873a4b16c9ba89

foo_abx 2.0.6c report
foobar2000 v1.4.2
2019-02-23 10:41:04
File A: Jennifer Warnes A.wav
SHA1: ede63a55290916546e1b3c1e820484a640e54847
File B: Jennifer Warnes B.wav
SHA1: b2267d2dfca51d73226afb57ddb9667adbc342f5
Output:
WASAPI (event) : SDAC (SDAC), 24-bit
Crossfading: NO
10:41:04 : Test started.
10:43:26 : 01/01
10:44:32 : 01/02
10:45:26 : 02/03
10:47:23 : 03/04
10:48:05 : 03/05
10:49:11 : 03/06
10:50:05 : 04/07
10:51:42 : 04/08
10:54:21 : 05/09
10:58:27 : 05/10
10:59:28 : 06/11
10:59:28 : Test finished.
----------
Total: 6/11
p-value: 0.5 (50%)
-- signature --
3ea6533699673105f4160107d07edfb7091de4f5

foo_abx 2.0.6c report
foobar2000 v1.4.2
2019-02-23 11:01:57
File A: Phil Woods A.wav
SHA1: 05c277bc622eeacf1109f6754a23e0c859c5a379
File B: Phil Woods B.wav
SHA1: 7646a7da269e70c05d60a0056c1165ecd1f3dbdb
Output:
WASAPI (event) : SDAC (SDAC), 24-bit
Crossfading: NO
11:01:57 : Test started.
11:04:31 : 00/01
11:09:59 : 01/02
11:17:51 : 02/03
11:18:24 : 03/04
11:19:01 : 03/05
11:19:30 : 03/06
11:20:50 : 03/07
11:21:31 : 04/08
11:22:29 : 05/09
11:23:11 : 06/10
11:24:52 : 07/11
11:24:52 : Test finished.
----------
Total: 7/11
p-value: 0.2744 (27.44%)
-- signature --
256cda182eecc0726c243a7e5f0202df2a72f96f

foo_abx 2.0.6c report
foobar2000 v1.4.2
2019-02-23 11:51:39
File A: Ry Cooder and VM Bhatt A.wav
SHA1: 2b1b878c4b8a31535a43ad9037ff3b582b1fe1c2
File B: Ry Cooder and VM Bhatt B.wav
SHA1: 1833211cbc558646d94a7e40ccfbc938e42dcafd
Output:
WASAPI (event) : SDAC (SDAC), 24-bit
Crossfading: NO
11:51:39 : Test started.
11:52:22 : 00/01
11:52:36 : 01/02
11:53:13 : 02/03
11:53:28 : 02/04
11:53:39 : 02/05
11:56:00 : 02/06
11:56:26 : 02/07
11:57:52 : 03/08
11:59:03 : 04/09
11:59:25 : 04/10
12:00:05 : 05/11
12:00:05 : Test finished.
----------
Total: 5/11
p-value: 0.7256 (72.56%)
-- signature --
fe98e0260781f0c5623100fc31dae58dd7ed5847

All right. Way to do the test. Well other than you didn't hear the difference.

 

[Krunok]

All right. Way to do the test. Well other than you didn't hear the difference.

Speaking of the results, what are yours?

 

[Veri]

Bob Marley A
Ry Cooder A
Cowboy Junkies B
Phil Woods B
Jennifer Warnes A

edit: yep I sure failed this test

 

[Blumlein 88]

Speaking of the results, what are yours?

I can hear all of them. It took some doing on the Cowboy Junkies and the Ry Cooder and V.M. Bhatt however. I couldn't hear them at 1st, 4th or 6th generation. I think if I flattened out the response with some careful EQ I wouldn't hear them at all. I did manage this before I knew there was some FR ripple.

 

[Blumlein 88]

BTW, if anyone has reported their results and not gotten a Conversation with the answers just let me know. I'll shoot you the guide to the recordings.

 

[Krunok]

I can hear all of them. It took some doing on the Cowboy Junkies and the Ry Cooder and V.M. Bhatt however. I couldn't hear them at 1st, 4th or 6th generation. I think if I flattened out the response with some careful EQ I wouldn't hear them at all. I did manage this before I knew there was some FR ripple.

Congrats!

Btw, is there any way you can make similar files that differ only in THD but not in frequency response? In ideal case the same recording would have different levels of THD, say 0.05%, 0.1%, 0.5%, 1% etc..

 

[solderdude]

Here is the frequency response after 8 generations. ..This was caused by the ADC which has a tiny bit of ripple which is more than tiny at 800%. ...

It would be fair to say that we were actually listening to the ADC in this case as this seems to be the bottleneck in this case and not the DAC.

It makes me wonder how many generations it would take before differences would be audible when say an RME would be used to record the DAC's output ?