Pre-Amp Pass Aleph L

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Probably L-Pad at the output that will attenuate a couple db.The latest is the one that to some point works as passive,yes?
I built the two versions of L preamp some time ago and I remember I liked the first (always active) more although the diffrance wasn't that big.Also the first version had the possibility of changing the gain (0,6,12 and 18db) by simple changing the diffrent resistor at the input.Also I've noticed thet Aleph L set for 6db gain had more gain that BLS set to 12db gain.I hope this helps a bit
Bartek
 
The easiest way to do it would be to put a voltage divider at the input. The exact values aren't critical. If you were to wire two 47.5k resistors in series, put one end to ground, the other end to the input jack, and take your signal from the mid-point, it would cut your input by 6 dB. Probably not enough reduction to do the job, but you get the idea.
Note that this will effect your Zin a bit (lower it), but it's a lot easier than replacing all the resistors in the volume control, plus it's something you can take out later if you want to.

Grey
 
Newby question here...

Why the divider rather than just a high quality resistor in line with the input?

By referencing to ground isn't there a possibility of injecting noise at the input of the amp? (I know the ground is supposed to be quiet but I also know lots of other appliances creating noise of all legs of the power supply....)

Curious?

Thanks!
 
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