Mono Blocks on a Budget, is it possible?


I’m really struggling with the direction to take my system. I have the following:

Legacy Classics speakers
Aurender N100H media player
Schiit Freya tube pre-amp
Schiit Yggdrasil DAC
Schiit Vidar x2 (in mono block mode)

I will be replacing speakers at some point but the rest of the system I love... except the Vidars. Before them, I had NAD 356BEE that was used for the amp. Very clean and I loved it, except it was only 80 Watts. I decided to upgrade to the Vidars. They cost twice as much From a good manufacturer like Schiit so they must be better right? Not really. They are more noisy than the NAD amp and I’m finding myself less in love with them that I though I would be. I was planning the Vidar purchase for about a year and now that I got them I don’t know which direction to take in replacing them. I want to get cleaner mono amps but don’t want to spend more than $3k MAX for both. The Vidars are 400 Watts into 8ohm, are there any options out there for me that are close to the Vidar specs? I’m open to used but mostly I want the amps to sound almost completely clean with practically no distortion. 
xerotrace
Wow some very good options. Thanks for all the input, I just wish I could hear all these to know which sounds best to my ears. That’s always the problem with this hobby it is often hard to test drive.
O.P. GREAT post lots of good leads and suggestions. Similarly, anyone using low priced Monos for 1.7 Maggie’s. I’m using a fresh re-capped and updated Krell KAV-250a, it sounds very good about 500W @ 4ohms.
Krell KAV250 is good, I used one for 2 years but remember it is really an av amp, hence the designation.
Not as good as ksa series
But still it is cheap power for sure!
Like $1200 used or so.