As someone who worked with Roger Modjeski for the last 5 years of his life, and to who (along with a couple other long time friends) he entrusted his business and legacy with upon his passing, I see I need to clear the air here.
A lot of facts about what Roger did and how he did it have gotten twisted over the years, to the point of becoming myths. Roger tried to set the record straight a number of times but finally gave up. I think he eventually came to view the myths as a source of humor, to the point of proliferating them. Roger and I spent his last few months speaking daily at length about many things audio (including the myths vs. reality) and personal. We listened diligently to his interviews with audio luminaries like Julius Futterman and Saul Marantz. I have all his notebooks and designs (at least the ones he documented) that I have been reading and studying so I think I have a pretty good idea of the man and his legacy when it comes to audio.
I got myself an RM-10 for a specific application, one for which the amp is perfect: the Quad ESL. Roger used that loudspeaker and the 16 ohm LS3/5a as his speaker load in the design phase of creating the RM-10, the Quad a notoriously difficult speaker to drive.
The Quad ESL was never used in the design process or as the load for the RM-10 and it’s debatable that his Chartwell LS 3/5a speakers were either. The Quad just happened to be the speaker Roger was using in his system when the amp was designed so after playing it on them just to get a listen to it he felt it was a good amp for the speakers, but a bit lean in the bass.
I have always used subs with my Quads, as did Roger.
Maybe you did but not Roger, although he certainly felt that it would be a benefit to do so, which is what he told me as he sat next to me listening to my RM-10 power my Quads. So next day at his shop we made up some woofers, I grabbed a solid state amp off the shelf, and Roger gave me a Beveridge RM-3 active crossover so I could biamp the Quads in my system and I never looked back.
In the 1980’s (I believe it was) Roger was hired by Harold Beveridge to design and build the tube amps included in the Beveridge ESL.
It was the late 70’s when Roger worked at HBI and this was probably the classic of all the myths. Roger never designed or built those direct drive amps. He did test all of them which is why you will see his name inside them, but design and build - no. Roger did design the Beveridge RM-1 preamp, it’s RM-2 power supply, and the RM-3 active crossover. Roger remembered this period of his career fondly as he got to focus on what he truly loved which was design work. As he often told me, at HBI I designed it, someone else built it, and someone else sold it.
Roger’s final product was not just his own ESL loudspeaker, but one with no input transformers (the cause of a lot of non-linearity).
Not by a long shot.