External vs. internal power supplies

[senn650fan]

How is it that some headphone amps have external power supplies and others have internal ones? I am referring to desktop type amps and not portable ones. Some manufacturers (e.g. Meier Audio) feature units with only internal PSU's while others (e.g. Headamp) feature units with only external PSU's. Is it better to have an external or internal psu? Can someone explain to me what a regulated power supply is. It seems all the amps around the $1k range have regulated PSU's. To quote from the Singlepower Audio website:

"The single most important aspect of tube audio design is the power supply! For most audio amplifier manufacturers, the power supply is often one of the most neglected parts of an audio amplifier’s design. Why? Because the power supply is the most expensive part of an audio amplifier! Many companies will offer the power supply that their equipment really needs as an "upgrade". The better designed, more powerful and better regulated the power supply the larger and more expansive the sound stage. An audio amplifier is essentially a modulated power supply."

Is the above really true and does it also apply to solid state amps? Do Singlepower Amps have better PSU's than Meier Amps or other manufacturers? I would imagine that headphone amps are no different that home theater amps in that a better PSU produces a more silent noise floor, but can a PSU actually "color" sound?


Thanks

 

[kramer5150]

I think some makers do it to help reduce costs, wall-wart PS for example. Others do it to keep as much physical distance, and mechanical shielding between the transformer and audio signal path.

I think...
Garrett