LaScala dac with telefunken tubes

Not all TF tubes sound the same. I have a TF E88CC early 1960's, which sounds positively shrill - but I also have 5 E88CC TF tubes selected for HP, also early 60's, and they are far the best 6922 tubes I have ever heard. 

Although, for all I know, that E88CC may be a clever counterfeit.

@tomcy6-

The Telefunken tubes that came in my DAC were not NOS tubes (as stated in my post). I upgraded to NOS after the tubes supplied with the DAC had been used for 3 years.

@terry9-

Do you regularly try different tubes for voicing the equipment you own? Which suppliers do you use?

OK.  Thanks @designsfx   I just wanted to clarify.  It's been a while since I've seen anyone supplying NOS tubes as stock.