Fyi, regarding my Zanden 1200 Mk3 phono, here is what Yamada-san told me about 2 1/2 years ago in response to my query:
1) Assuming the power supply is left on constantly,, what is the approximate interval the tubes (2 x 6CA4, 1 x 6922) should be replaced?
2) Do you have a preference for brands for the power supply tubes?
3) Can I purchase the power supply tubes from you directly?
4) Regarding the 6922 tubes in the audio unit, I know these are always subject to individual preference, but before I open the unit up, can you tell me what brand of 6922 you are currently using for the 1200 MkIII?
Dear Martin-san,
I try to answer your questions.
1) The tubes runs only when you turn on the switch on the front panel. The life of power supply tubes is long.
You don’t need to change until the sound quality goes down or you can find some distortion from your speakers.
2) NOS EZ81 in EU, Sylvania and GE 6CA4 in USA.
3) I can send them to you, but you don’t have to purchase our regular rectifier tube EH 6CA4.
Because you can buy them easily in your country.
4) I think the best is TELEFUNKEN CCa, MULLARD 7308 SQ and next is SIEMENS E88CC gold pin, SYLVANIA 7308 etc.
I am using PHILIPS 6922 for model1200 mk3. Because I can get them easily and the cost and sound quality is acceptable.
Best regards,
Kazutoshi Yamada
Technical section
Zanden Audio Systems Ltd.
address: 1558-1 Amakadaki-cho
Kishiwada-city, Osaka Japan
596-0845
Since I am in love with the 1200 Mk3, I will not deviate from the tubes that Yamada-san used to voice his phono stage. The recti is a NOS Mullard EZ81. I have 2 back-ups for that Mullard and 2 for the GE 6CA4 a NOS set of 3 Siemens E88CC, and NOS set of 3 Dario Miniwatt/Philips 6922. That should take me well past the year 2050, maybe even to 2070!