There's a big improvement to change the original tubes in aynon's CD player, I'm the owner of a CD-1, and was not satisfied with the little sound hardness remaining after break in, so I went for a pair of 6H30-DR instead of the original ones and switched the EH 6922 to a pair of Siemens Cca. The player is not the same ! Best improvement came from 6H30 DR, but be patient they take quite a long time before being at their top (at least 100 hours). Switching 6922 was not a so big improvement excepted to correct some sibilance on the top treble and change slightly the medium sound. I auditioned recently the CD-2, in comparison the definition is much better, coming partly from the real symetric implantation of components and mainly, to my point of view, from the PCM 1704 Dac (same as the one in the Audiomat Maestro).
But honestly I have the same result by coupling the CD-1 with a Whest Audio DAP 10 (unfortunately discontinued), this little box is quite a mystery for me, same effect as a high end DAC. Also coupled with a Burson audio buffer it gives interesting results (personally I connect the CD-1 in RCA to the Whest audio and in XLR with the Burson Audio buffer, both give a different sounding and I switch according to the kind of music I listen to).
But honestly I have the same result by coupling the CD-1 with a Whest Audio DAP 10 (unfortunately discontinued), this little box is quite a mystery for me, same effect as a high end DAC. Also coupled with a Burson audio buffer it gives interesting results (personally I connect the CD-1 in RCA to the Whest audio and in XLR with the Burson Audio buffer, both give a different sounding and I switch according to the kind of music I listen to).