SET vs OTL

"In a nutshell you have to be really careful about making broad stroke statements; when comparing SETs and OTLs it can go both ways insofar as to which comes out on top."

Agree and it absolutely does go both ways. This topic has been discussed numerous times on this and other forums. I’ve compared SET and OTL directly and would choose SET just as @antigrunge2 did.

@audition_audio has done similar comparison and finds OTL superior. Okay fine, his experience and good for him. We don’t need proclamations, just choose what you conclude is better. I’d never declare SET universally superior to OTL, NOR would I do the converse.

Plenty of music listeners have made the choice for OTLs and plenty have done so for SET. Why do we need to draw lines in the sand and have turf battles when it comes to audio components and listening preferences? People have moved on from SET to OTL and from OTL to SET.
Charles

My speakers are Duevel Bella Lunas with 6 ohms impedance and 93db efficiency. To run the Graaf I used Paul Speltz Autoformers to step them up. I used Bybee Golden Goddess Speaker Bullets in both instances and Auditorium23 speaker cable. 

In a nutshell, hypothetically, if the speaker is a "very easy drive without any hindrance" at all to either amp, the OTL in class-A will be the better amp full stop.

BUT!! for an OTL not to be hindered IN ANY WAY at all by todays "better sounding speakers loads" that have NOT had "their sound compromised" (because they were designed "firstly" too give a very easy load), is a big ask.
And those type of "very easy to drive speakers" usually have big other glaring problems to many listeners that are susceptible to their colorations,  so it’s a bit of a catch 22.

Cheers George

The autoformer used as an impedance matching device is, in effect, an output transformer.  It is doing exactly what an output transformer does.  To me, if something sounds good, I don't care how it got there.  I've heard many great tube amps, and I would not dare to say if any particular topology beats out another.  My personal favorite happens to be an OTL amp, but, it is an utterly unique, one-of-a-kind design.  A very close second (maybe not even second) is a pushpull amp that is extremely rare and costs six figures for a pair (Western Electric 59A).  I own a pretty good SET amp (Audio Note Kageki) and I've heard many other good SET amps, but the amp I currently run in my system is a low-powered pushpull amp.  

I know the Duevel line fairly well. What I would like to know is how low the impedance actually goes and with what type of swing. I agree that using an auto-former somewhat defeats the purpose of an OTL and would not be an option for me.