Cyngus 859, IF you heard a correctly set up CAT SL1 you should have heard a MAJOR MAJOR jump in SQ over your SP6C. I had an SP8 in my system and I can tell you the CAT is in a whole different league. To really hear what the CAT can do, you have to have upstream gear that can let the CAT shine. I also believe to get the last few ounces out of the CAT, tube rolling is recommended.
The SP10 Mk2 is also a very good preamp, BUT still not quite up to a CAT, IMHO.
The SP10 Mk2 is also a very good preamp, BUT still not quite up to a CAT, IMHO.