DK Design VS.1 Reference mkII - Optimization

I also don't understand the 'wave' concept, I can understand EM fields of changing intensity, but 'waves' which bounce back and forth off some surfaces but not others? Are you aware of any science which supports this?

Tvad, Audioaril, Tom, anyone - please help me to understand this.
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I sure can't, and that's why I'm not convinced EMI effects are the reason Audioari1 hears benefits with the DK top off. If Tom's vibration theory is correct, then why would the amp sound better with the top off? More vibration causing additional microphonics in the tubes? I have heard some claim that microphonic tubes...just below the threshold of causing ringing and echo...sound more spacious and open, and therefore "better".

Audioari1, in what ways does the DK sound better with the top off. Would you please describe what you hear?

Tvad, I'll take a stab at the vibration/top issue, by way of example. I have a CDP with case vibrations induced by the transformer. These vibrations are sufficient to rattle the tube innards which increases any potential they have to be microphonic. When I take the top off the CDP I'm eliminating one of the surfaces which facilitate the transmission of the vibrations. Often the audible (as well as physical) frequency (pitch if you will) and intensity of the vibration changes - usually lessens. Mass loading can have a similar effect.

If you have the best LN tubes and your unit has a low noise floor you might not actually change anything except reduce the audible transformer hum (not a bad thing at all), but if you have borderline tubes and a highish noise floor these vibrations can induce tube microphonics which can be audible. FWIW, I think there are better ways of getting 'spacious and open' than using microphonic tubes. :-)

I think I misunderstood Tom's point. I thought he was suggesting that removing the top increased vibration due to a less rigid case structure (which is the case in automobiles...coupes being more rigid than convertibles in the same models), when it appears Tom was suggesting that removing the top decreases case vibration. Sheesh, I'm confused.

I don't know whether to remove my Magic Fingers motel bed from my listening room, or to keep it in.

Hey guys my thoughts were that removing the top changed the vibrational pattern and therefore the sound...for the better or for the worse. I am very comfortable with myself knowing that vibration can be given a pattern as well as direction in all things that are in motion, which is everything. Removing the case which is more likely less massive than the main chassis would probably reduce the amount of various resonance points that could be transfered back to the main chassis and electrical components to be reamplified in the mix. Most of you know my previous history and thoughts ..mass loading versus mechanical direct coupling..anyway the case removal altered the vibrational direction and flow..Proper mechanical grounding of all the boards, transformer and power supply caps to the main chassis and all of this direct coupled to a greater mass {the floor of your home} would transfer vibrational energy away from and out of your component..The result would be greater resolution and dynamic scale. So I have experienced.. Tom

07-08-06: Theaudiotweak
Hey guys my thoughts were that removing the top changed the vibrational pattern and therefore the sound...for the better or for the worse.

Indeed.