WHAT HAS WORKED FOR YOU? ISOLATION PLATFORMS, FOOTERS, ETC. for a DAC?

Hi David,

You are moving in the right direction IMO.

"Soft" footers "cushion" the component from external vibration from the floor/rack but also trap internal vibrations inside the component (isolators vs conductors).

Symposium Acoustics system of combining Rollerblocks with their Svelte shelves (conduct then isolate) drains the vibrations from both the component (on top) and from external vibrations from the floor/rack (from below) into the vibration-absorbing membrane sandwiched between SS plates. Detail and coherence are improved over soft (and hard) footers, cones, and Rollerblocks without the shelves IME

Adding spring devices underneath the Svelte shelves (I use Solid Tech) can improve the sound further for extremely sensitive gear.  

Dave

Unfortunately it’s not really a question of "microphonic immunity." There is nothing you can do to make a component - any component - immune to low frequency seismic type vibration, I mean other than isolate it from those vibrations using some type of low pass mechanical filter. That’s because the entire building is shaking, so anything connected to it is shaking right along with it.

Obviously some steps can be talken (but usually aren’t) inside the component to guard against vibration with higher frequencies, you know, using damping techniques,including those produced by the component itself such as transformer hum, CD transport mechanical noise, motor noise, etc.

Right Geoff. I use vibration damping material inside the chassis and stick-on wheel weights on transports/CD players to good effect.

There seems to always be room for improvement in this area.

Dave

Interview discussing microphony and other design choices. The important takeaway is that some designers choose to tackle power supply and microphony issues and others ignore them. If you buy a DAC that is not designed to eliminate these issues then of course you can spend far more than you spent on the DAC itself trying to fix power supply and microphony issues.

http://www.stereo-now.co.uk/interviews-Benchmark.html

"In a well-designed system the DAC chip is the limitation. Anyone who is building “high-end” products that are limited by power supply performance should find a different “d**n” business."

"Before any product is released to market, we subject it to very high levels of vibration while listening to the noise floor and while viewing the noise spectrum on a high-resolution audio analyser. Any disturbance in the noise floor is an indication that a microphony problem exists. We also tap each component with a ceramic probe while listening to the noise floor. Benchmark products are not microphonic and can be used in high sound pressure and/or high vibration environments without isolation accessories."

On the DAC2 and DAC3 the power supply is switched Mode and this new form of power supply running at very high frequency has eliminated all the 60Hz hiss and hum issues that come with a linear power supply.

Benchmark is not the only maker of excellent sounding DACs but I present their design philosophy here to show that not all designers ignore the problems of power supply and microphony - so choose your products wisely or else you face the challenge of trying to get them to work properly through the use of band-aids!

Tapping noise and 60 Hz noise is not why we employ isolation. Those are examples of higher frequency vibration and induced vibration. One needs to address induced noise, airborne vibration AND low frequency seismic type vibration. Even solid state amps and power supplies, .i.e., things with no moving parts or things that seem solid, should be isolated. The printed circuit boards and wires are all subject to vibration. For components with transformers on board the transformer should be isolated from everything else, especially the printed circuit boards. Bolting the transformer tightly to the chassis is probably one of the dumbest things manufacturers ever did. And they’re blissfully unaware of the issue. Or, if they are aware they dismiss it.