Forthcoming from cpo:
https://www.jpc.de/jpcng/cpo/detail/-/art/friedrich-theodor-froehlich-saemtliche-streichquartette/hnum/8455687 (https://www.jpc.de/jpcng/cpo/detail/-/art/friedrich-theodor-froehlich-saemtliche-streichquartette/hnum/8455687)
The set is now on sale at jpc...
https://www.jpc.de/jpcng/cpo/detail/-/art/friedrich-theodor-froehlich-saemtliche-streichquartette/hnum/8455687
I am currently listening to the first of these string quartets (in F minor, from 1826) and have been immediately captivated by the opening movement's earworm of a main theme. In fact, Fröhlich's fund of melodic inspiration is evident everywhere in this lovely work.
Here (http://www.unsungcomposers.com/forum/index.php/topic,5818.msg61523.html#msg61523) is an earlier thread about Fröhlich.
I transcribed two of the quartets a few years ago. I think they are quite a mixed bag. Some charming melodies, but they show the inexperience of the composer (he composed all of them while studying in Berlin; it is not clear if he showed them to his teachers; I suspect he didn't; any teacher would have made him correct the parallel fifths and octaves...though they don't bother the majority of listeners). Most obviously probably in the variation movement that opens the g-minor quartet. The theme is really impressive; the first variation consists of figurations for the first violin (à la Haydn) and is entirely uninspired as well as entirely unviolinistic. There follow some inspired variations and some more uninspired ones. The Rasumowsky people add on to the boredom by playing all repetitions (the first violinist has no more ideas what to do with the first variation than I have but plays every note, one after another with zero expression in a rather slow tempo; I am not very happy with their performances anyway.
Unfortunately they did not include the piano quartet (http://www.unsungcomposers.com/forum/index.php/topic,6616.0.html) which is from 1835, one year before his suicide. It is considerably more mature. BTW this second thread about Fröhlich contains some more information (including Santo's devastating judgment of the quartets).
According to Swiss Radio SRF2 a CD containing the piano quartet is in the can.
Anyway it will be broadcast in February:
https://www.srf.ch/audio/ch-musik/aargauer-romantik?id=11916424 (https://www.srf.ch/audio/ch-musik/aargauer-romantik?id=11916424)
Possibly on the Coviello label?