Sirspeedy...Very good. The CCa of early vintage offer a very smooth, yet textured sound. Very palpable compared to the later CCa's and other Siemens tubes IMO. The highs should be more smooth but maybe less transparent than the Edi's. The bass will be more robust on the CCa's...but perhaps not as tightly defined as the Edi's..you'll have to hear for yourself for sure. You can always resell either tube after you give it some time to evaluate them.
OLcm--I forgot to make mention of my new favorite 6922 Im using in my ARC PH3SE phono pre amp. I replaced my early CCa's with a trio of Russian(yes...you read correctly!) 6H23n-eb SLNM Cryo's tubes available from Ken( no relation either personally or professionally) at ATSI in Florida. This tube is killer in every way and has to my ears all the sonics we want in a tube. Linear, yet warm. Detailed and resolving..yet not at all bright or grainy. Excellent bass without bloat or tubbyness and miles of depth and soundstage abilities that embarras many NOS tubes....Bottom line...If I were lookoing to retube my LS15 now..I would definately give these tubes a whirl. A matched pair is about $75.00 and well worth the cost for a quad....Ken
OLcm--I forgot to make mention of my new favorite 6922 Im using in my ARC PH3SE phono pre amp. I replaced my early CCa's with a trio of Russian(yes...you read correctly!) 6H23n-eb SLNM Cryo's tubes available from Ken( no relation either personally or professionally) at ATSI in Florida. This tube is killer in every way and has to my ears all the sonics we want in a tube. Linear, yet warm. Detailed and resolving..yet not at all bright or grainy. Excellent bass without bloat or tubbyness and miles of depth and soundstage abilities that embarras many NOS tubes....Bottom line...If I were lookoing to retube my LS15 now..I would definately give these tubes a whirl. A matched pair is about $75.00 and well worth the cost for a quad....Ken