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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
dazzdax OP
599 posts
 
Shardone, with transformer based passive preamp you will get high input but low output impedance. I think with saying that a passive preamp is a "terrible mistake" some of us would feel offended (btw, myself not included).

Chris
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.
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