The EtherREGEN thread for various network, cable, power experiences and experiments

[Duke40]

On 12/31/2019 at 7:47 PM, JohnSwenson said:

One very important thing to understand is that the IR emission from a black surface is vastly greater than from a bare metal surface, so putting a bare metal heatsink on top of an ER will actually increase the  temperature of the case because you are almost stopping the IR emission. If you DO use a heatsink make sure it is black!

 

This brings up another interesting way to cool the thing, put a black thick aluminum plate under the ER, the bottom will transfer a lot of heat to the plate through IR, which then spreads out through the plate into the environment. You could also make that into a nice anti vibration platform.

 

 

I have a number of 10mm thick Aluminium plates it was bare metal, and I remembered this post you made last year, so I painted them black on the weekend.

 

Have noticed both of my ER temperature drop considerably.

 

As a test tonight, I left one right side up with the rubber feet still attached, the other upside down (to see if a closer, direct contact would further reduce the temperature. Oh, by the way, the aluminium plates still have several markings & swirls underneath to help prevent standing waves (from a post you made several years ago on another AS thread regarding vibration/resonance control). Please excuse the mess, my network is undergoing several changes.

 

[Duke40]

On 10/8/2020 at 6:58 AM, JohnSwenson said:

This combination does a very effective job of blocking seismic waves from reaching the crystals in the oscillators. As far as I have been able to tell seismic waves (very low frequency waves in the ground, caused by ground heating and cooling and nearby trucks or trains) are one of the biggest contributors towards oscillator output contamination. These temperature change induced seismic waves are one of the reasons a lot of people like listening in the middle of the night, the ground temperature has stabilized thus produces much less intense seismic waves.

 

Unfortunately there is a correlation that the oscillators with the lowest phase noise also have the highest sensitivity to seismic waves, so measures like these can become quite important for very high quality digital systems.

 

A few words on the aluminum slab. The 1/2" thick aluminum plate has several very good properties one one bad property.

 

The good:

thick aluminum is a good absorber of higher frequency vibrations. It is good shielding both for electrical waves AND magnetic waves (thin aluminum sheets do not shield well from magnetic fields, but thick ones do). At 1/2" it is very rigid so provides a good base for dealing with the low frequency seismic waves. Sheet metal (particularly the case of most electronics) bends at these low frequencies significantly decreasing the effectiveness of the roller bearing

 

The bad:

thick aluminum "rings" like crazy. This after all is how wind chimes work. It turns out the ringing is caused by surface acoustic waves forming standing waves on the surface of the aluminum. Fortunately this can be damped out by things touching the surface, thus scattering the patterns and preventing standing waves. On the bottom this is the balls through the mirrors, for the top just putting your equipment on the top disturbs the waves enough to prevent the standing waves.

 

Apart from painting the Aluminium plates black (I use them as part of my "anti vibration/heat absorbing/shielding" platforms, I placed an IsoAcoustics Aperta 300 stand underneath the ALU plate. The Aluminium no longer rings like crazy. 

 

The top shelf of my network rack, which holds my ERs is also isolated from the rack by using 3 Townshend Audio Seismic Pods, which do a pretty good job of dealing with the seismic wave issue. I'm kind of using the Pods in a similar manner to your use of the roller bearings.

 

I'm doing a bit of experimenting at the moment, though eventually I need to clean up the cables once I have settled on a final support system for both of my ER's, as I until I take care of cable dressing, I may be causing some "mechanical shorts", reducing the effectiveness of the "anti vibration/heat absorbing/shielding" platforms.

 

Three things I have noticed in my testing over last few weeks (for platform under my ERs):

1)  Black. Painting the Aluminium black changed the temperature of the ERs from hot, to just warm.

2) PRAT. Placing the IsoAcoustics Aperta 300 stand under the Aluminium plate got rid of the Aluminium from ringing, and Pace, Rhythm and Timing improved.

3) Raised Soundstage, more articulate bass (and the other usual stuff that the Townshend Audio Seismic Pods bring benefits for). I was thinking of the line you wrote "Unfortunately there is a correlation that the oscillators with the lowest phase noise also have the highest sensitivity to seismic waves, so measures like these can become quite important for very high quality digital systems.", and wanted to provide an ideal environment for the ERs by taking care of seismic issue, so used the Pods.

 

Just my thoughts, Townshend Audio Seismic Pods do a better job in the vertical plane, IsoAcoustics do a great job especially in the lateral plane, the use of Aluminium (which no longer rings due to IsoAcoustics), and then painting the Aluminium black, all brought beneficial changes. I think it has a special synergy.

 

For underneath my JS-2, I tried Black 10mm Aluminium plate on top of an IsoAcoustics stand, did not notice any real change. Its the ERs which like really benefited from the support system described above.