Yamaha CDX-10000 vs. Creative Audigy 4, Need help of interpreting sigle-blind hearing test (CD-player vs. PC) Options

[hdablin]

I need help in interpreting test results.
Preface:
I have a home stereo system: CD-player + amp + speakers.
I want to replace my CD-player with a PC with high-quality soundcard (here is my thread about choosing the one). I'm afraid to loose the sound quality of CD-player.

One of the members, Arnold B. Krueger (many thanks!!!) proposed me to run a blind test, to prove that I really can hear difference between the PC and the CD-player. Now, here is the results of the test.

Test environment.
1. The first source is Yamaha CDX-10000 cd-player;
2. The second source is an average PC with Creative Audigy 4 (SB0610) soundcard (I was luckely gifted).
3. We use two albums for our test:
a. KorovaKill - WaterHells
b. Various Artists - Wir Rufen Deine Wolfe

Both of the sources are connected to the same amplifier and speakers.

Test methodology.
First of all, it was only single-blind test, not double-blind one. The second is the test was not actually an ABX test (I do not have an ABX-ing hardware device). The test was processed as following:
1. My friend was an operator, and I was a listener. Both sources was turned to the max volume (0dB), the amplifier's volume control was not touched during the test;
2. We make two test sessions (I do not see or discuss the results before the sessions was ended). We use one of CD for one session;
3. Each of sessions was processed the next way:
3.1 I wake out of the room;
3.2 My friend throwing the coin to choose which of source to run, then she using Bash random generator to choose test track within the CD;
3.3 I entered the room (by eyes was covered, so I cannot see the equipment or the operator), I listened the sound and tried to guess which source is actually plays;
3.4 I left out the room (to avoid hearing of coin's fall or swithching the sources);
3.5 The next iteration begin.

Test results:

CD 1
Try No. |Real source|Track No.|My Guess|
1. | Copmuter | 10 | Computer
2. | Computer | 11 | CD-player
3. | CD-Player | 10 | Don't know
4. | Computer | 3 | Computer
5. | CD-Player | 5 | Computer
6. | Computer | 5 | CD-player
7. | Computer | 9 | CD-player
8. | CD-player | 11 | Don't know
9. | Computer | 12 | Computer
10. | CD-player | 10 | CD-player
11. | Computer | 8 | CD-player
12. | CD-player | 9 | CD-player
13. | CD-player | 9 | Computer
14. | Computer | 5 | Computer
15. | CD-player | 2 | CD-player
16. | Computer | 3 | Computer
17. | CD-player | 9 | Don't know
18. | CD-player | 6 | CD-player
19. | Computer | 1 | CD-player
20. | Computer | 4 | Computer
21. | CD-player | 1 | Computer
22. | CD-player | 5 | Computer
23. | CD-player | 10 | Don't know

CD 2
Try No. |Real source|Track No.|My Guess|
1. | CD-player | 10 | CD-player
2. | Computer | 7 | Computer
3. | CD-player | 6 | Computer
4. | CD-player | 4 | CD-player
5. | CD-player | 6 | Computer
6. | CD-player | 12 | Computer
7. | Computer | 6 | CD-player
8. | CD-player | 3 | CD-player
9. | Computer | 4 | Computer
10. | Computer | 7 | Computer
11. | Computer | 3 | Don't know
12. | CD-player | 2 | CD-player
13. | CD-player | 3 | CD-player
14. | CD-player | 11 | Computer
15. | CD-player | 2 | CD-player
16. | Computer | 6 | Computer
17. | CD-player | 1 | CD-player
18. | CD-player | 6 | Computer
19. | Computer | 5 | CD-player
20. | CD-player | 6 | Computer
21. | Computer | 10 | Computer
22. | CD-player | 2 | CD-player
23. | Computer | 8 | CD-player

The questions:
1. How can I interprete the results (actually, this test was not an ABX, so I don't know, weather I can use ABX-interpreting method described in the FAQ).
2. How do you think, was this test enough accurate to make some desicion?
3. Does it really mean that I cannot hear any difference between the sources?

[Brand]

Glancing at the results, it seems like you didn't manage to hear a difference.

But regarding the methodology, I'll repeat what I said in another thread, just in case: you should use the same input on the amp (for example "CD") for both sources. Not all analog inputs are audibly the same. (Perhaps in theory yes, but I've had a case of an amp where an input was audibly different.)

[mixminus1]

Also, "Both sources was turned to the max volume (0dB)" does not guarantee that they were level-matched - you need to play some test tones and actually measure the voltage outputs of the CD player and sound card to make sure that they are really outputting the exact same level, as our ears tend to give preference to louder sources, even if they don't actually sound different.

[hdablin]

Glancing at the results, it seems like you didn't manage to hear a difference.

Yes, I'm thinking the same.

But regarding the methodology, I'll repeat what I said in another thread, just in case: you should use the same input on the amp (for example "CD") for both sources. Not all analog inputs are audibly the same. (Perhaps in theory yes, but I've had a case of an amp where an input was audibly different.)

Thank you for the comment. But I didn't hear difference, so, I think that both analog input sound the same for me (because output sounds from the speakers are the same).

Also, "Both sources was turned to the max volume (0dB)" does not guarantee that they were level-matched - you need to play some test tones and actually measure the voltage outputs of the CD player and sound card to make sure that they are really outputting the exact same level, as our ears tend to give preference to louder sources, even if they don't actually sound different.

I've running some volume calibration tests (playng well known tracks) before starting. Neither me, nor the operator heard volume difference. I have no technical possibility to measure the volume objectively, but it seems that volume levels were equal.

This post has been edited by hdablin: Jun 6 2011, 12:32