In Reply to: passive preamp question posted by Randy Bey on January 20, 2001 at 06:36:22:
Here's my take on the passive preamp situation.
A passive preamp is just a few extra connectors, one or two switches and an extra set of interconnects in the signal path so there is really no way IT can do much damage to the signal, compared to an active linestage.
When people say they experience a loss of dynamics associated with their passive, I generally look towards their source as the culprit. i.e. their CD player, phonostage, etc. doesn't have the drive capability of a high quality preamp. Most high quality preamps are built with beefy, well designed power supplies...but look under the hood of your favorite $2000 CD player and you may be disappointed in what you find for a power supply.
So I suspect if are loosing dynamics with the use of a passive linestage, even if you could connect the CD player directly to the amp (i.e. bypass the passive) you would still not have the dynamics.
And thus, I've found that with better quality source players one will not experience this loss of dynamics.
So the moral of the story is....if you like passive linestages, then either purchase better source equipment, or break out your chainsaw and modify/upgrade your existing players.
When selecting an attenuator value for a passive, generally, the lower the value the better. If all of your source equipment is solid state with a low output impedance, then go with a 10K. If you have a tube CD player or tube phonostage, then go with a higher value (20-50K) so as not to load down their outputs.
Ron
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