PrimaLuna preamps. Use of 5R4GY tubes instead of 5AR4 / GZ34. Yes or no?


Post addressed to the owners of Primaluna preamplifiers. Have you tried to replace the 5AR4 / GZ34 rectifier valves with 5R4GY? Although the valves have completely different values, they are recommended as an upgrade on the Primaluna website and by UPSCALE Audio.
https://www.primaluna-usa.com/tube-rolling
I would like to try these valves on my Prologue 3 but I am afraid of some breakage.
I would like to know your experiences.
Thank you.
Alessandro
128x128yukio
Hi TubeGB
so you had no problem using the 5R4GY instead of the 5AR4 / GZ34 on the Prologue 3.
Have you used them for a long time?
What improvements did you perceive?

yukio:
I have used them (Philips 5R4GYS) for several years now. Improvements are a little more warmth on the top end and a small increase in sound stage width.
I failed to mention the Philips tube is substantially taller than the stock 5AR4 tube and when in position you will no longer be able to use the tube cage.
Please note again that as a general rule, it's not a good idea to deviate from a 5AR4 tube and it remains a good idea to consult with Upscale Audio.
yukio,

Simply either go by what is on the website or call Kevin Deal at Upscale Audio, he is directly involved in PrimaLuna beyond selling them