Bought a pair of Magnepan LRS. Should I buy a Schiit Vidar or Bryston 3B-ST?

Usually with Magnepan, the more power the better, but current is less critical than most so less beefy high power amps may work quite well.

I had a Carver m4.0t amp (tube amp like SS design), 360w/ch into 8 ohm, not much more into 4, that matched with my Magnepans better than most. Not so much with other more power and current hungry speakers, much as would be expected with most higher output impedance tube amps.

The Bryston is a good amp and more then twice as powerful I believe.....I would choose the Bryston.

Hello areasonableman,

     I agree a Bryston would be a good option.  Based on my knowledge and experience,  The Class D Audio 470 will be about equally as powerful as the Brystons but will be more detailed, have better perceived bass response although a bit exaggerated due to a higher damping factor, have lower measured distortion levels, have a noticeably lower background noise level, better dynamics and will have a more neutral overall presentation.  However, the Brystons by comparison will impart a 'warm flavoring' to everything played through it that many seem to enjoy.  In other words, the 470 will be more accurate and the quality of the recording will not be masked in any way.  If you're listening to a bad recording, it will not be as obvious when amplified by the Brystons.  If possible, I suggest you listen to both to determine which overall presentation you prefer.
     If you prefer the warmer less accurate overall presentation, this can also be achieved with the choice of preamp you pair with the 470 amp. In general, tube preamps will impart varying degrees of warmth depending on the brand, model and exact tubes utilized;  solid state preamps will generally impart less warmth and are more accurate, although there are exceptions to this general guideline with both preamp designs.

Tim
      

Just hooked up my LRS to a 4BSST and a BP20 with MPS-1 and wow.  Rocking the house, the bass is there I mean not 20 hz obviously but enough to satisfy without the REL subs I was using before.  It's a big room, I'm using a "knock out" side with the coat closet to create this bass effect.  Perhaps not as "sweet" as the Conrad Johnson with top of the line NOS Mullard tubes from Uncle Kevin, but I do like my Bryston sound and quiet background. 

Areasonableman,
Those toroids are small value chokes and are probably NOT part of the power supply, though they could be.  More importantly, broken as they are, they will NOT work properly and need to be replaced.  I wouldn't bother with much listening until they are fixed.  To work properly they rely on a continuous toroid iron ring.  If that ring continuity is broken it will not work correctly.  Who knows if it was UPS or some other cause, but GET THEM FIXED!

Aerasonableman,
Don't get suckered into the game of high powered amps. Yes the Maggies do need a high current amp with sufficient power to drive them but just because you have a 100 watt amp does not disqualify them from playing the Maggies. It all depends on your amps power supply. I have Prima Luna Premium Dialogue HP amp rated at 85 watts per channel with KT 120 tubes. This amp has huge output transformers that control the bandwith, so it doesn't matter if you have 100 or 1,000 watts your only going to use probably 5 watts.