The Maggie 1.6 have a very benign 4ohm load but a low sensitivity of 83db, a good Solid State amp of 100-200w that can do 4ohm on it ear should be a good choice.
http://www.stereophile.com/content/magnepan-magneplanar-mg16qr-loudspeaker-measurements
A good push/pull tube amp with 100w or more and 4ohm speaker tap will do also, but it should have a lowish output impedance, below 1ohm, zero feedback tube amps are out, as they are generally too high in output impedance, as negative feedback reduces the output impedance.
I can think maybe some S/H Rogue 120 monoblocks or 150 monoblocks these can also be switched to Triode from Ultra linear and have a good low output impedance and a 4ohm speaker tap, and tight bass for a tube.
PS: Ron I don't know if you are in California but there is a pair of Rogue 120 for sale here
http://app.audiogon.com/listings/tube-rogue-monoblock-m120-amplifier-2013-11-25-amplifiers-90036-los-angeles-ca
Cheers George