The title is a jest, of course. Karl Höller is no pen name for Hindemith. You won't find much biographical fodder in the short paragraph that serves as liner notes on this DG reissue, other than the fact that Höller was Bavarian like conductor Eugen Jochum and studied in Munich with Joseph Haas. His dates are 1907-1987, making him a near-contemporary of Jochum (1902-1987). If you read German, you'll find more on Deutsch Wikipedia, including the fact that he received from Josef Goebbels the National Prize for Composition in 1940, that (unlike Jochum whose career in those years was notwithstanding very similar) he joined the Nazi Party in 1942, and that in August 1944 he was added by Hitler on the so-called "God-Blessed List of Important Composers", enabling him to escape conscription.
Anyway, all those dubious acquaintances didn't prevent him from becoming Professor of music at the Munich Conservatory in 1949, and Dean from 1954 to 1972. The Germans in those years were very forgiving. Questions came later.
Going from link to link I've been able to establish that the "Symphonic Fantasy" opus 20 on a theme of Frescobaldi was written in 1935 and revised in 1956 and that the Sweelinck Variations op 56 were composed in 1950/51: that's much more info than you'll get on this CD.
Quite honestly, I had never heard of Höller (the only Höller I know is contemporary German composer York - I don't know if there is a relation, although York, born in 1944, could very well be Karl's son) and I chanced upon this CD on one of my now very rare outskirts to the "real" store. The disc's production info gives June 1957 as recording date for the Frescobaldi Fantasy, but October 1987 for the Sweelinck-Variations, which is obviously a typo: 1957 seems more likely.
The title about Hindemith wasn't JUST a jest. Seeing that Jochum conducted these two works I expected that I wouldn't be hearing any cutting edge contemporary music, nothing like Bernd-Alois Zimmermann and possibly nothing even like Karl-Amadeus Hartmann. Orff and Hindemith seemed as far as Jochum might go. Spot on. Hearing these two sets of orchestral Variations, it is striking how much they sound as if they had been composed by Hindemith, particularly in their fast sections. All the hallmarks of Hindemith' style are present: the boisterous, forward-momentum, the dotted rhythms of fast marches, the piercing-woodwind dominated or brassy textures (try track 2 & 4 of the Frescobaldi Fantasy, and about all of the Sweelinck Variations except 12 & 15). You could be in the Weber-Metamorphoses or Mathis-Symphony. I guess the Nazis were content to ban Hindemith and still have his music played, provided it was written by someone else (this of course is valid only for the Frescobaldi Fantasy). The slow sections don't sound as Hindemithian. They are mostly elegiac, well-crafted which doesn't mean they display much more personality. They sound like the slow movements of the symphonies that some of the less original and distinctive American composers of those days might have written (let me mention no names here).
I'm not saying that the music isn't pleasurable. I personally love the music of Hindemith and I enjoyed this. Still, it is derivative.
As mentioned, there are as good as no notes, and TT is a short 49:21. Sound is mono but clear and well-defined. So this must be reserved to collectors of the off-the-beaten-track. The "lay" music-lover should be redirected to the original: Hindemith himself.