Absorption of digital hash

@greg_f . In a review of Alpha Reference mention of "material" added to absord radiated digital noise, nothing complicated.

Thanks guys. I've found Holland Sheilding System as a result of your helpful comments. Now will do some shopping :)

Yes. Radiated. Berkeley owners must know...

@erik_squires . Like to improve my Oppo 205 without any upgrades. Just read about Berkeley as I'm considering dac upgrade ( or Spectral spinner). Still love disc movies on my Sony 4k. Mu metal for transformer 'may' be interesting. I'm just getting back to listening. Been busy w project. Relaxation coming up-again :)  Time to ponder hi-fi improvements. Your comments always interesting/informative/ mannerly :)

Material was added under top plate.

This is the comment from Mr. Harleys' review of the Dac 3. I'd like to know the material.

"When I removed the Alpha 3’s top panel, I noticed a square of material above the digital-to-analog conversion section, just as in the Reference. This ultra-expensive material absorbs and diffuses RF energy. Noise radiated by circuits is absorbed rather than being reflected from the top panel back into the circuit board."

Thanks for all helpful responses. I don't have a problem I have an Oppo 205 and thought if this material is good enough for Berkeley it's probably goid enough for Oppo. I have no complaints with my Oppo.