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RE: Passives

No it doesn't.

Your active preamp has gain, your passive preamp does not.

A 12:00 to 3:00 setting of the volume control on your preamp equals unity gain and gives the same signal voltage to the power amp and the same volume out of the speakers as your passive pre turn all the way up.

Either way the power amp is doing the same amount of work. That is made evident by the speakers outputting the same SPL into the room.

There's an easy test you can do.

Get a 60Hz test tone off the internet. Open it in a audio editor like Sound Forge. Normalize it. (That sets all the peaks and valleys of the wave form at a digital zero)

Loop it so it's a few minutes or so in length and then burn a CD of it.

Play it in your CD player and measure the output voltage of the player with a AC voltage meter (any multimeter will work).

Now do the same with the signal going through the passive pre adjusted to max. (the output voltage should be about the same)

Now do the same again with the signal going through the active pre.

Adjust the active pre so that it's output is the same as the passive pre set to max. (according to what you said that setting will be somewhere about 12:00 to 3:00)

With the active pre set to the same signal output voltage as the passive pre, the power amp receives the same amount of signal voltage from the CD player and it therefore is doing the same amount of work.



Tre'
Have Fun and Enjoy the Music
"Still Working the Problem"

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