有谁知道这张碟?
我<<MY DISC>>这张测试碟的详细中文介绍,有谁知道?或给个联接,谢了! 挑选音源的试金石《MY DISC》(我的碟)摘自《电子报》2003.9.28 作者：小反
有没有不借助仪器就能试出器材性能的CD碟呢?回答是肯定的。由喇叭花唱片推出的《My Disc》(我的碟)就是这样一张猛碟。它不仅用于挑选音源，还用于整个音响系统的甄别、摆位调校以及煲机、练耳，用本碟的第33段—第42段，会把音源的极限状态考出来。
第33-41段为相同的爵士乐片段，第33段为标准电平0dB，以后每段减弱lOdB直到-90dB，第42段为完全寂静，在第33-37段之间还容易听得清晰每个乐音，随着声音越来越小，你可以逐渐开完功放的音量，把耳朵贴在喇叭上……。
这时音源的噪音也开始显现出来，器材的解析水平也将水落石出，最后乐器声越来越难显现出来，许多乐音将在噪声之中挣扎直到最后完全淹没在噪声中。有许多器材在后几段中将出现声音发破，或者有汽船声、电流声，或者是光头读碟时伺服电路工作发出的怪声，不一而足。我曾听到过有每秒响一次规则的“嘟呼”声(结果是显示屏电路秒闪干扰)，越好的器材越能听到高的段位，并且噪音越低越好，许多号称用 PCMl704作DA转换的CD机都过不了这关。
……(据说世界上最猛的解码器应能完整解出第 41段，并且在第4l段和第42段之间还能听出本底噪音有一点差别，那对我们来说只能是一种可望不可及的神话了)……
第42段的用处是绝对寂静，它和机器暂停时不一样。大家知道许多CD机在暂停时都要发出静音指令以切断输出(静噪门打开)，所以听第42段和机器暂停时不一样，前者是反映机器通路畅通时电路的噪声水平，器材的设计功底一目了然。
——市面上的VCD机在第38段还可以过(有的连第38段都解析不出来)，但噪声已成汪洋，一片沙沙声，很难辨出乐音来。第39段已成大海捞针，曾经去掉
过一机的OK电路，也只能是减低部分噪声，没有根本的改变，可见是D／A转换器的精度太低，机内数字、模拟、视频电路互相干扰。
——近几年来国产DVD设计上有了长足的发展，写这篇文章时测过最新款的单芯片DVD(机型：奇声 DVD8831——本机主观听音高频较硬)，本底噪声较低，在第39段弱音开始发破，第40段乐音开始调制噪声而引起声音完全变形(这可能就是本机主观听音高音较硬、毛的原因)，第41段静噪门打开(静音)，第42段3秒时静噪门关闭，本底噪声低到令人满意。
兴致中我还连续对比了几款奇声DVD，基本上第 39段和第40段都有类似的调制情况，在第41段和第 42段会出现静噪门打开的情况(静音)。当然，拿CD机的要求来强求价值几百元的DVD机可能勉为其难口巴。
——入门名机马兰士63SE(音色温暖)，这款机型听第38段的弱音有断音，第39段声音时断时续、打嗝(但不乱)，估计设计时对弱音打开静噪门(静音)，整机噪声较低，第41段和第42段静噪门打开(静音)，宁可让其无，不可让其乱，这也是它音色温暖的原因，即虽性能不是很高却深受乐迷喜爱的原因。
——在听过的器材中解析最好的要数奥斯1900解码器(声音中性自然灵动)，第40段较完整，极弱音已不能出来，第在41段乐音的强音能冒出几颗，但是没有乱的感觉，弱音已不在。印象极深的是这台机器本底噪声非常致密平和，这是印象中听过最利害的机器(按：此机设计者为原杭州中裕公司总工贺建华，现在美国加州硅谷的电脑公司工作)。
——在写这篇文章时还测过家里的SONY X333ES(音色厚暖)，采用磁悬浮线性伺服机心，模拟和数字电路独立供电设计，噪声水平极低，几近奥斯 1900的水平，但第40段中声音就开始断弱音(但没有乱的感觉)。本机播李娜《苏武牧羊》缺少奔放张狂之气，让笔者一直引以为憾，感觉李娜唱得平和，没有了野性，可是每次换上奥斯1900或DAC-I总能让人感动于这张碟的大气和奔放，场景历历在目，里面的人和物都又活过来一回，又重演一幕历史的千古绝唱……
——曾听过一款用双片PCMl704作DAC的CD机(声音动态凌盛威猛)，用本碟测试，在第39段声音已发毛混有许多高频噪声，第40段完全无法听清乐音，噪音和乐音交织在一起，机内虽采用双变压器数模独立供电，但设计排版布线有很大问题，此机售价虽高，但用本碟立现原形。
经过以上实测可以得出如下结论，乐迷选音源应选能完整听完第39段，有可能的话最好能完整听完第40段的机型(但银子已直线上升)，噪声可接受并和乐音不互相交调即为电路设计不错。最后要提醒大家，在用本碟测试时一定要注意音量的掌握，特别是在听第38-42段之前要先全面听一下这几段和第43段，并注意掌握好时间，以免听过了段位而损坏设备和耳朵。
CD: The Sheffield-A2TB Test Disc: "My Disc" - The Sheffield-A2TB Test Disc: "My Disc"
Sheffield Lab 10508-2-T
01. The Power of Seven - Up Front / Stranger In My Bed
02. Thelma Houston - I've Got The Music In Me / Dish Rag
03. Prokofiev's - Romeo & Juliet / Dance of the Knights
04. Adam Makowicz with Phil Woods - The Name is Makowicz / Dirty Blue
05. Michael Ruff - Speaking In Melodies / Wishing Well
06. Lincoln Mayorga & Distinguished Colleagues - Vol. III / Dock of the Bay
07. 1 KHz sinewave at -20 dBFS
08. 1 KHz sinewave at 0 dBFS
09. 20 Hz one octive warble
10. 62 Hz one octive warble
11. 125 Hz one octive warble
12. 250 Hz one octive warble
13. 500 Hz one octive warble
14. 2.5 KHz one octive warble
15. 5 KHz one octive warble
16. 10 KHz one octive warble
17. 15 KHz one octive warble
18. 19 KHz one octive warble
19. Person Counting from 1 to 25
20. Right Channel Identification
21. Left Channel Identification
22. Relative polarity between left & right channels
23. Polarity pulses
24. 1 KHz sinewave with bottom half clipped
25. 3 people describing position on sound stage in stereo
26. Same as track 25 except talking simultaneously
27. Music for evaluating accuracy and focus of sound stage in stereo
28. Same as track 27 except in mono (L + R)
29. Same as track 28 except sent to left channel only
30. Same as track 28
31. Same as track 28 except sent to right channel only
32. Same as track 27
33. Music recorded with normal transfer level of 0 dB
34. Music recorded withl transfer level of -10 dB
35. Music recorded withl transfer level of -20 dB
36. Music recorded withl transfer level of -30 dB
37. Music recorded withl transfer level of -40 dB
38. Music recorded withl transfer level of -50 dB
39. Music recorded withl transfer level of -60 dB
40. Music recorded withl transfer level of -70 dB
41. Recording of Digital Black or 0 bits
42. High Frequency low level alternating between 0000 & FFFF
43. Correlated pink noise 20 Hz to 20 KHz
44. Uncorrelated pink noise 20 Hz to 20 KHz
45. Pink Noise raised in 1 dB steps every 3 seconds
46. Pink Noise raised in 3 dB steps 4 times
47. 1/3 octive Pink Noise at 25 - 31.5 - 40 Hz
48. 1/3 octive Pink Noise at 50 - 63 - 80 Hz
49. 1/3 octive Pink Noise at 100 - 125 - 160 Hz
50. 1/3 octive Pink Noise at 200 - 250 - 315 Hz
51. 1/3 octive Pink Noise at 400 - 500 - 630 Hz
52. 1/3 octive Pink Noise at 800 Hz - 1 - 1.2 KHz
53. 1/3 octive Pink Noise at 1.6 - 2 - 2.5 KHz
54. 1/3 octive Pink Noise at 3.15 - 4 - 5 KHz
55. 1/3 octive Pink Noise at 6.3 - 8 - 10 KHz
56. 1/3 octive Pink Noise at 12.5 - 16 - 20 KHz
57. 20 Hz to 20 KHz continuous warble
58. 100 Hz to 20 Hz warble for subwoofer evaluation
59. Individual frequencies from 10 Hz to 99 Hz
60. Flat low distortion sweep from 20 - 200 Hz
61. Flat low distortion sweep from 200 Hz - 2 KHz
62. Flat low distortion sweep from 2 - 20 KHz
63. Contains the musical note A (440 Hz)
64. 100 Hz tone burst with duty cycle of 25%
65. Same as track 64 except at 1 KHz
66. Same as track 64 except at 10 KHz
67. 100 Hz square wave
68. Same as track 67 except at 1 KHz
69. Full dynamics of the original recording
70. Compressed version of track 69 with same peak level
71. Tone with 0.03% distortion
72. Same as track 71, except with 0.1% distortion
73. Same as track 71, except with 0.3% distortion
74. Same as track 71, except with 1% distortion
75. Same as track 71, except with 3% distortion
76. Same as track 71, except with 10% distortion
77. Music with distortion of about 0.03%
78. Same as track 77, except with 0.1% distortion
79. Same as track 77, except with 0.3% distortion
80. Same as track 77, except with 1% distortion
81. Same as track 77, except with 3% distortion
82. Same as track 77, except with 10% distortion
83. Musical selection with no added delay
84. Same as track 83 with 7 mS of group delay below 100 Hz
85. Standing between Penske's pits and main straightaway
86. Short walk down pit row of race car track
十分感谢ZONEBOUN朋友，让你费心了。
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