Hello jt35,
Yes, you ’re correct and that’s been the advice from Magnepan as long as I can remember. Typically recommending at least a 100 watt class A or AB amp that doubles its power into a 4 ohm load. It’s the main reason that I always used various class AB stereo amps with my Magnepans for years, a variety of 200-400 watt amps such as Adcom, McCormack and Aragon mainly with a tubed VTL 2.5 preamp. They all sounded very good and similar.
About 4-5 years ago, after reading many mainly highly favorable reviews on the newer class D amps at that time here on Audiogon and other audio forums, I became curious and bought a Class D Audio SDS-440-CS stereo amp to audition in my system to drive my older pair of Magnepan 2.7QR speakers that are still in very good condition and utilized in my system today. I chose this amp because it was rated at 440 watts into 4 ohms, I’d read many very favorable reviews on it from owners as well as professional reviewers and it only cost $540 at that time.
I wasn’t overly optimistic about its performance once it arrived since it was about 1/3rd the size and weight of my current and previous class AB amps that were all very large and weighed up to 85 pounds. This amp did have a traditional linear power supply with a toroidal transformer, and not a switched mode power supply (SMPS) like some other class D amps. but it still only weighed about 15 pounds.
Even after installing this little amp and playing it right out of the box without any warm up, however, it was obvious to me that it performed and sounded better than any other amp I had used in my system driving the Magnepans in all the aspects I’m normally concerned with. The background was inky black and dead quiet, I had never heard or felt better bass response and dynamics from the 2.7QRs and didn’t even realize since owning them that they were capable of such powerful, detailed, dynamic and natural bass quantity and quality. I was actually a bit stunned and very pleasantly surprised.
The midrange and treble performance of the class D amp was not as significantly superior than my previous class AB amps. Overall in the midrange/treble and imaging qualities, the class AB amps I’ve used have given me the impression of being more similar than different sounding than the class D amps I’ve since used with the exceptions of the class D amps being more neutral in character, slightly more detailed and with a bit better dynamics. In my experiences, both are equally capable of delivering smooth and natural midrange and treble performance with good imaging and without sounding overly harsh or bright.
However, I’ve also noticed the class D amps are definitely more revealing and less forgiving on source material that is poorly recorded, mixed or produced. I tend to appreciate this accuracy and honesty but realize some may not.
But I’ve also read several good reviews on the Schitt Vidar amp. Steve Guttenburg of the Audiophilliac states on this You Tube video review of the LRS speakers that the Vidar is a good choice to drive the LRS speakers:
https://www.youtube.com/watch?v=gdqchci3AhU I’m just suggesting that Mr. Reasonable may want to audition a good class D stereo amp or pair of monoblock amps on his LRS speakers before buying a Vidar amp in order to make a better informed decision.
Best wishes to the OP, areasonableman,
Tim