I know that a lot of these amps are the same and just had different names based on what cabs they came with, correct?
Solarus = Sceptre, Sonaro = Sorado?
According to the catalogs, the Solarus and the Sonaro were
combo amps. Until 1970, they were also fundamentally different amps; rated at 40 watts using EL34's vs. the 60 watts using KT88/6650's that the Sceptre and Sorado were rated at, and
all of them were tube rectified. The Sorado and the
200S were the same
amp, but the Sorado had a less expensive 2 x 15 "Sunn Transducer" loaded cab with two circular ports rather than the 200S 2 x 15 JBL D140 "folded horn" cab.
In 1970, everything went 6550 and SS rectified, and were rated at 80 watts, but again per the catalog the Solarus and Sonaro remained as combo amps. I've read posts from people who claim to have head versions of the Sonaro and Solarus, and there is no doubt that anomolies did exist at Sunn, but they may
also just be combo amp chassis slid into head cases.
Who knows? I do know this, the "catalog thread" sticky that Loudthud put forth so much effort to compile is an absolute
treasure trove of information.