The Holy Grail of 12AT7's
My Doshi tape head preamp shipped today and due to arrive in a few days. Nick Doshi arrives on Saturday to integrate it with my Studer. The switch had been previously made but Nick needs to make an internal board to modify the switch.
Nick uses 3 pair of 12AT7's one pair in the output stage and one pair in each of the NAB and IEC settings. Since I never listen to NAB recorded tapes I elected to roll only 2 pair of these tubes and after a lengQthy search I was able to find a quad matched set of Telefunken NOS ECC801S circa early 60's which are brand new and never been used. All four tubes have the same serial number and the measurements on all 4 tubes are almost identical. Needless to say I bought them and they will be integrated into Nick's unit
Here are some photos as these are as rare as hen's teeth.
Stay tuned. I am really looking forward to getting this unit into my system
Bottom of the tube showing the famous "diamond"