Another + for the v281 paired with the LCD-4s.
The Violectric V281 drives the LCD-4 with aplomb, and all my other cans as well. I have never heard any type of noise on it at all, but then again, that is probably where the DAC that is attached to it, or some other link in the component chain become important. The way any amp sounds depends on the DAC it is associated with in the same chain (there is no getting around that), as it depends on transducers, and even on interconnects, and often too, the headphone cables one is using (I could even go into power cables, and the electrical field, but let's just keep those aside for now). In other words, the sound of any amp, at any given time, is a product of the system synergy of the amp, together with other components and cables that are deployed in the same chain... What will make or break that chain, with regard to its sonic performance, is always the weakest link in that chain, whatever that link is (and that link is not necessarily, and not always the amp).
My Violectric V281 is deployed--because of its great versatility with input/output and sound-controlling options-- as one sort of center-piece in three different chains of components, two of which are feeding headphones. The third chain serves the front tower speakers of my 2-channel Stereo/HT systems.
1. Ultra-rendu (Roon-endpoint)==>> Schiit Yggy A2 ==>> V281 ==>> Headphones
2. Metrum Acoutics Ambre (Roon endpoint) ==>> /Metrum Onyx/Schiit Yggy A2 ==>> V281 ==>> Headphones
3. U-rendu/Ambre (Roon endpoints) ==>>Onyx/Yggy A2 ==>>> V281 ==>> Emotiva XMC1 (pre pro) ==>> Polk Audio LSIM 707 towers.
The V-28i has been in these chains for three years now, although some of the surrounding components that are currently listed are replacements of others that were in similar positions in prior arrangements of essentially these same overlapping chains...
I have used the following headphones on V281 at the same or different times: Hifiman He 500/He-6/He-1000/He-1000SE, Sennheiser HD-600/6XX/700/800, Audeze LCD-X/LCD-MX4/LCD-i4/LCD-4.
I guess you could say that it has been thoroughly tested over these years, and it has always sounded as clean as a whistle, no matter what I have thrown at it. None of these headphones has sounded "bad" in anyway on it, but some of them scale better on it than others, and I can confidently tell you that the LCD-4 is among those which scale the highest on the V281 in these chains.
Again, it has been used in this way for 3 years, and has produced no noise whatsoever : zero, zilch, nada. Of course this account is based my own listening experiences, on the components I have listed in the above chains, and others I have not cared to... YMMV