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Preamplifier power supply

Hi folks, should a preamplifier have a BIG (that is: an overkill power supply) to sound dynamic and authoritative? I'm asking this because some experts would say "yes" while others would say "no". Recently a well known audio journalist (Anthony Cordesmann?) said that the preamplifier doesn't have to have a big power supply because it doesn't have to deliver lots of energy (in the form of current). A preamplifier can sound "dynamic" even with very modest power supply --> for example the built in preamplifier in the Benchmark DAC. But some manufacturers rely on a truly overkill power supply in their reference preamplifiers: MBL, First Sound Audio, BAT, VTL, LAMM, Mark Levinson. So who is right?

Chris
dazzdax
elizabeth
6,726 posts
 
In 'cost no object' pre..of course, have big everything! For $20K you should expect it.
In the real world, folks make choices about what sort of compromises they are willing to make. When I consider a $2K preamp.. I listen to the sound. Not whether it has a "big Gonzo" along with the mandatory two giant spheres.
Plenty of pre's sound really great with modest power supplies. Including many separate power supplies, which inside that box may have a small transformer and small caps!
The size of a pre's 'tranny' is not the final word. Ditto not what 'caps' or the thickness of the chassis and front panel...
shadorne's avatar
shadorne
7,333 posts
 
I think with saying that a passive preamp is a "terrible mistake" some of us would feel offended (btw, myself not included).

Ooops sorry - good point. However, there is a good reason for OTL designs: transformers are simply not the greatest of devices when it comes to linearity.
johnss
291 posts
 
Chris, that is a question many have asked. A larger transformer and power supply has helped every pre amp I have ever tried it on from the Japanese mfgrs all the way up to the high end gear from Jeff Rowland, Threshold and Mark Levinson. A nice 600 watt toroidal transformer will cost 80-120 dollars plus an outboard case to hold it, since almost no manufacturers use a power supply of that size.
ngjockey
1,042 posts
 
There is some talk about this subject on the PSAudio site that's fairly amusing.

Shadorne: My preconceptions were the same as yours. Techies have a hard time with that one.
dazzdax OP
599 posts
 
Ngjockey, could you tell the link to the PSAudio discussion?
John, still some do not concur with this preconception. I would like to know why this dichotomy exists. It reminds me of the tube vs solid state discussion.

Chris
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