The Black Hole

Vibration Tests

Part Two

Here is the audio output of a 1kHz square wave at -12dB. The horizontal blue line charts circuit board vibration, the red line charts the audio signal.

Without The Black Hole:

Square Wave Without The Black Hole

With The Black Hole:

Square Wave With The Black Hole


The two square waves look virtually the same. One small glitch on the first square wave shows a correlation between circuit board vibration and the output signal:


Square Wave/Vibration Correlation

These jaggedy lines represent micro-vibrations of high frequencies and very low amplitude. Something like this showing up once in your favorite recording would go by unheard and unnoticed. If this glitch were repeated 1,000 times every second though, perhaps it might tweak the audible portion of a musical note or orchestral passage with a slight tinge? We believe so.

The little red vibration above is approximately 40kHz, a pitch beyond human hearing and at a nearly imperceptible amplitude. You would not hear it. The vibration is not isolated of its own, though; it is part of a larger square wave and sufficient to render the whole square wave just slightly out of phase or to oscillate in and out of phase minutely. Listened to on its own, this would make no difference to the listener. In relation to other parts of a stereo montage, however, a slightly out-of-phase frequency can have profound effect on the acoustical rendering of soundwaves. You might very possibly hear the effect on stereo imaging and tonal character. A soundwave just barely out of phase with a complementary soundwave will attenuate that frequency and affect that portion of simultaneous tones. In a stereo recording, soundwaves appear in all various degrees of in-phase and out-of-phase--this gives a sense of natural ambience and atmosphere. When phase relations come out of the speakers other than how they were intended, the audible result is other than what is intended. A soundwave that's not in proper phase can likewise falsely amplify other parts of the musical mosaic, causing brightness, sibilance, bloopy bass and a host of other sonic anomalies.

Of course the first and most important step to superior music reproduction is to start with a very good player. Here is the same square wave reproduced with a Pioneer Elite DV-59AVi without The Black Hole, with all other conditions identical to the square wave test at the top of the page:


1kH Square Wave with Pioneer Elite

The Pioneer square wave is much smoother, with less circuit board vibration (the blue line) and quicker rise/fall. No surprise that it sounds better, but it also costs a lot more than the inexpensive Sony.

It seems like The Black Hole can make a cheap player sound better. But how can The Black Hole bring a better-quality player like the Pioneer Elite up to the next level?

It seems to be in the resolution of very low level information.

Part Three