10-Jan-2024, 18:40
Dear all,
while trying to improve the power supply of my system, a strange phenomenon occurred, the cause of which appears to be my Expert 220 Pro. I would be grateful if there was a clue to the cause or possible solutions here in the forum. So:
I first tested two different filter systems, one of which was a Puritan PSM156. (There are already other Devialet owners here who have had good experiences with it.) The phenomenon occurred that a linear power supply that was also connected began to hum when the Devialet was switched on.
This surprised me because the outputs in these filters are shielded from each other. However, the buzzing occurred in both filters, and so I assumed that the linear power supply might be defective. But then:
Since I wasn't really convinced by the sound of the filters, my dealer recommended a technically different solution, an Audes ST-1500 as an isolation transformer. This is really very satisfying in terms of sound - although clearly more expensive, but also a very clear step forward from any filter solution that I know of. BUT:
Now the Audes hums when the Devialet is turned on. And it's not quiet, so something you could tolerate, you can hear it at distances of up to 8 meters. In a kind of elimination process, the following can be said so far:
- the Audes only hums when the Devialet is switched on.
- This happens even if nothing else is connected to the Audes or Devialet.
- the Audes does not hum with other amplifiers, although we have only been able to test A/B amplifiers so far.
- An additional DC filter looped between Audes and Devialet does nothing (as expected).
We were able to reproduce the problem with a friend's Devialet 440 Pro Dual on an Audes ST-3000. Therefore I assume that my 220 is not defective, but that we are dealing with a quirk of the Devialet Experts.
Because of our work with filters, my friend and I already know that the Devialets return about 600mV of EMI radiation per device into the network. But here the phenomenon seems to occur that the Devialets also reflect DC, but we are not sure.
Does anyone here know this problem and can say something about it? I would be very happy.
Digant
while trying to improve the power supply of my system, a strange phenomenon occurred, the cause of which appears to be my Expert 220 Pro. I would be grateful if there was a clue to the cause or possible solutions here in the forum. So:
I first tested two different filter systems, one of which was a Puritan PSM156. (There are already other Devialet owners here who have had good experiences with it.) The phenomenon occurred that a linear power supply that was also connected began to hum when the Devialet was switched on.
This surprised me because the outputs in these filters are shielded from each other. However, the buzzing occurred in both filters, and so I assumed that the linear power supply might be defective. But then:
Since I wasn't really convinced by the sound of the filters, my dealer recommended a technically different solution, an Audes ST-1500 as an isolation transformer. This is really very satisfying in terms of sound - although clearly more expensive, but also a very clear step forward from any filter solution that I know of. BUT:
Now the Audes hums when the Devialet is turned on. And it's not quiet, so something you could tolerate, you can hear it at distances of up to 8 meters. In a kind of elimination process, the following can be said so far:
- the Audes only hums when the Devialet is switched on.
- This happens even if nothing else is connected to the Audes or Devialet.
- the Audes does not hum with other amplifiers, although we have only been able to test A/B amplifiers so far.
- An additional DC filter looped between Audes and Devialet does nothing (as expected).
We were able to reproduce the problem with a friend's Devialet 440 Pro Dual on an Audes ST-3000. Therefore I assume that my 220 is not defective, but that we are dealing with a quirk of the Devialet Experts.
Because of our work with filters, my friend and I already know that the Devialets return about 600mV of EMI radiation per device into the network. But here the phenomenon seems to occur that the Devialets also reflect DC, but we are not sure.
Does anyone here know this problem and can say something about it? I would be very happy.
Digant
