ブラインドテストは信頼できますか? Are Blind Tests Reliable?

私たちがテストを行う数週間前に、シークレットフォーラム貢献者は、Stereophile編集主任ジョン・アトキンソンによるブラインドアンプテストのレポートに私たちを誘導しました。雑誌は1989年にソリッドステートのAdcom GFA-555(750ドル)と同じように強力なtubed VTL 300W monoblock(4900ドル/ペア)を使っています。 完全なレポートは http://www.stereophile.com/features/113/index.html で見つけられるかもしれません。
In the weeks preceding our test, a Secrets forum contributor guided us to a report by John Atkinson, Stereophile Editor-in-Chief, of a blind amp test the magazine had conducted in 1989 between the solid-state Adcom GFA-555 ($750) and the similarly powerful, tubed VTL 300W monoblock ($4900/pair). The complete report may be found at http://www.stereophile.com/features/113/index.html.

そこから簡潔に引用します:
To quote briefly from that report:

アンプの違いを聞きとれる重要性に関する論議の多い問題で、何も人々を分極するように思えません。主観的な違いがあると思うなら、あなたはオーディオマニアです。 違いがないと思うなら、あなたはオーディオマニアではありません。そして、確立した知恵はクチコミ(非オーディオマニアの)を確認してください。アンプもレシーバーも価格がいったんあるレベルを超えると、音質におけるどんな更なる改良も無関係になるということです、どんな見かけの利得のためにも価格を提供しないので。 言い換えると、アンプのこととなると、「もっと」よいというものがあります。しかし、この雑誌の読者として私は、それにはあなたがいるだけではないと予想するでしょう。コンシューマリポーツが同じに聞こえるように、見なすアンプの本当の主観的な上質の違いに露出されます。あなたはそのような違いを聞くことに基づいて購買決定をさせました。
“Nothing seems to polarize people as much as the vexed question concerning the importance of audible differences between amplifiers. If you think there are subjective differences, you’re an audiophile; if you don’t, you’re not. And as any glance at an appropriate issue of Consumer Reports – the publication for non-audiophiles – will confirm, the established wisdom is that once the price of an amplifier or receiver crosses a certain threshold, any further improvement in sound quality becomes irrelevant, in that it puts the price up for no apparent gain. In other words, when it comes to amplification, there is such a thing as being “too” good. Yet, as a reader of this magazine, I would expect that not only have you been exposed to real subjective quality differences between amplifiers that Consumer Reports would regard as sounding identical, you have made purchasing decisions made on the basis of hearing such differences.

“It has often been said that the only way to resolve this apparent dichotomy is to use carefully controlled blind listening tests, where the listener does not know what he or she is listening to. In this manner, imaginary differences should fall away, leaving real differences that can then be correlated with objective measurements. Unfortunately, as you will have noted, for example, from David Clark’s infamous blind amplifier test in Stereo Review, it seems that with such blind listening tests, all perceived subjective differences between amplifiers (apart from those due to level, absolute polarity, and amplitude-response differences) fall away. The conclusion then drawn by some observers is that, indeed, once above a certain performance threshold, amplifiers do sound alike.

“But when you have taken part in a number of these blind tests and experienced how two amplifiers you know from personal experience to sound extremely different can still fail to be identified under blind conditions, then perhaps an alternative hypothesis is called for: that the very procedure of a blind listening test can conceal small but real subjective differences. Having taken part in quite a number of such blind tests, I have become convinced of the truth in this hypothesis. Over 10 years ago, for example, I failed to distinguish a Quad 405 from a Naim NAP250 or a TVA tube amplifier in such a blind test organized by Martin Colloms. Convinced by these results of the validity in the Consumer Reports philosophy, I consequently sold my exotic and expensive Lecson power amplifier with which I had been very happy and bought a much cheaper Quad 405 – the biggest mistake of my audiophile career!

“Some amplifiers which cannot be distinguished reliably under formal blind conditions do not sound similar over lengthy listening in more familiar and relaxed circumstances.

“There is also the fact that the ability to reliably hear differences between hi-fi components varies considerably from person to person . . .”

今日の人気記事