McIntosh 501 or 602 for Magnepan 20.1

I power my MG-20's with a combination of Threshold SA-1s with a Pass labs 350.5. The 350.5 sounds great on these speakers and powers them effortlessly. So even if you are not going to bi-amp your maggies I would suggest you add the Pass labs 350.5 to your audtion list. I see no problems because of not using a standalone pre-amp in your setup with the 350.5. Good luck in your audtioning ,your MG20.1s are amazing speakers!

Don't even think about the Paraounds JC-1s on the 20.1s. I tried them and they were pushed to their limit. Their transformers are too small. They can't deliver enough voltage. You need a very powerful amp either a Classe Omega, Rowland, Levinson, or one of the high-powered ARC amps if you want tubes.

Another great tube option is the Jolida JD 3000A 200 watt mono blocs. My Maggie dealer uses these as the default amps for the 20.1 and 3.6. He also happens to sell more Magnepan speakers than any other dealer in the U.S.

Huge power from the 211 tubes, never lacking anything. Banish any thoughts of a subwoofer. And you'll likely never go back to SS, certainly not the ever over-hyped, over-priced bricks like Levinson, Musical Fidelity, Krell, etc.

Gladstone: Parasound JC-1 pushed to the limit with the MG20.1s??! That does not sound right. Maybe you had issues with your power connection to the JC-1s, or some other problem.?

I run my 20.1s with a pair of JC-1, and IMHO the JC-1 powers the 20.1 effortlessly! I'm currently adding a 2nd pair of JC-1s for a bi-amp setup, and frankly I'm a bit worried that putting 2x800W into one 20.1 will be too much...

Peter

It won't be too much. It should sound a lot better with more power.
Yes, the JC-1 can run the 20.1s, but it doesn't control them the way a truly high-powered amp does. Just look at how little the JC-1s weigh. The real bruisers weigh 100-200 pounds a piece because they have big power supplies. I'm using the JC-1s on a pair of Magnepan 1.6s, where they sound much better.
Instead of getting another set of JC-1s, I'd save some money in your place and get the Classe Omicron or Omega, MK. 1. Far superior. I had them side by side. No contest.