2 Questions on tube replacement


I am using an Icon Audio PS-1 MKii phono stage.

My record suddenly stopped making any sound at all. I noticed that one of the three output tubes was not firing, so I am going to try replacing it.

The phono stage takes 3 ECC83/12AX7 tubes.

My two questions are:

1 — Can I substitute ECC803 for the ECC83s?; and

2 — Do I need to switch out all three or only replace all one at a time?

Thanks in advance.

saulh
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The 7025’s can be icing on the cake if you can find them. I used to get mine on Ebay. Agree with the comment about the gain on 5751’s being potentially problematic. My previous Muzishare x7 did not like those.