Preamp Noise with High-Efficiency Speakers

He has tried all that and more.

Quote from the OP:
whenever I insert an analog preamp. If I run my DAC (AMR DP-777) directly into power amp, the noise disappears. I have tried 4 different preamps (tube and SS), 3 different amps, a bunch of RCA and XLR interconnects, the problem persists. I have tried dedicated power line and two power conditioners (with Multi-wave options) and various high-quality power cords, so far nothing works, and I am forced to run DAC-direct into power amp.

Cheers George

An isolation transformer from Jensen it different from what he has tried.

I agree. He should have to use it. I liked the sound of a past system and the
only way I could keep,same components was to use a Jensen ISO tranny.

It rid the system of a buzz I could not tame in any other manner. Not ideal
as you say, but it worked and did not change my sound. In my case the
issue was between the amp and preamp. It was a buzz.

Just an idea.

The OP can call Jensen as they are very helpful and they can help
determine if this would be a strong potential fix. I bet they would be open to
letting him try and return it if it does not,cure the problem.

Almag here is the one who turned me onto the idea as well as another
Agoner who had the same issue and the Jensen worked wonderfully.

I assume here a nice tube preamp would deliver better sounding music and
this step is thus worth it.

Charles1dad said:

My point is don`t be condescending and dismissive to those listeners who chose an active component rather than his.

I agree completely. I think that you have to look at the LSA in terms of value. It's an outstanding value and a very good pre-amp. George, I second Grannyring's accolades for your DIY support (this from someone whose DIY skills pretty much end at crimping spades and rolling tubes ;-)