Faut-il bichonner le serveur ? (et jusqu’à quel point ?)

[ThierryNK]

Vacuum a écrit : …
Et quelle différence entre une alimentation à découpage et une autre alimentation à découpage ? 

J'aimerais bien le savoir ! 
..

C’est une sacrée digression qui concerne plutôt les amplis, mais bon, il y aura peut être deux ou trois trucs qui pourraient titiller les fans d’alimentations dites linéaires. 

Citation :  

• Resonant Switch-Mode Power Supply Most high-end power amplifiers use unregulated linear power supplies. The conventional wisdom is that linear supplies are electrically quieter than switching supplies. Benchmark's research shows that this is a myth. Linear supplies have transformers that operate at the AC mains frequency. The problem with these 50 to 60 Hz transformers is that they must be very large in order to supply the required power. These large low-frequency transformers generate large stray magnetic fields that can interfere with other nearby devices, and with the amplifier itself. The noise performance of many traditional power amplifiers is limited by the amplitude of the AC line-related hum. This hum is often magnetically induced and is very hard to eliminate. To solve these problems, Benchmark now uses switching power supplies in all of its newer products. Switching frequencies are set well above the audio band. More importantly, the high switching frequency greatly reduces the size of the magnetic components and the magnitude of the stray magnetic fields. Resonant switching is used in the AHB2 to minimize switching noise. Resonant supplies switch at low voltage and low current and are much quieter than traditional switching supplies.
  
  
• Regulated Power Supply - Audio amplifiers usually use unregulated supplies. The theory is that the amplifier can produce higher peak output power for a given power supply size. Linear regulation would throw away power that could be delivered to the output devices. Benchmark's move to switching supplies changes the efficiency equations. Switching supplies can produce a regulated output without wasting power and without creating unwanted heat. A further advantage of regulation is that the output voltage is not a function of AC line voltage, prior audio content, or speaker loading. The switching supply in the AHB2 responds to bass frequencies, maintains a constant low-ripple output voltage, and delivers very predictable output power.
  
  
• Low Stored Energy - Most audio power amplifiers rely on a bank of large capacitors for energy storage. These capacitors remove some of the ripple produced by an unregulated linear supply, and help reduce supply sag in order to maintain a high output level immediately following musical peaks. Unfortunately, these capacitors also slow down the recovery from voltage sag due to peak loading. Benchmark's approach is to nearly eliminate all storage after the power supply. The power supply regulation takes the place of energy storage, responds quickly to peak loading, maintains very low ripple voltage, and provides immunity to AC line-voltage fluctuations.
  

https://benchmarkmedia.com/blogs/applica...lification