the Telefunken are Telefunken E88CC 6922 CCa
And the Siemens are E88CC 6922 SIEMENS
If as you said one is brighter than the other i am sure it will not be as popular as the other tube, being that my buyers wanted a warmer sound of the ages (Which i am not to familiar with, being a digital man myself). We are building six hot swap boards for our Vi unit all have different tubes, different capicitors, and different connection pieces and transformers. So far one of those boards will have,
Tube Telefunken E88cc 6922,
with Jupiter capacitors,
Cardas XLR connections
a Lundahl balanced transformer on a single board for swapping.