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Preamp Rectifier Tube Confusion

I have a Primaluna Prologue 3 which uses 5AR4 rectifier tubes which id like to roll. I’m looking at ShuGuang WE274B tubes which list as replacements for 5AR4 / 5U4G / 274B. 
However, the Primaluna manual lists compatible tubes as: GZ34, CV1377, 5V4G, 5T4, 5Y3 and Upscale Audio also list the Philips 5R4GYS.

Any idea if the ShuGuang would work?
jl1ny
wolf_garcia
6,794 posts
 
I have a "preferred series" (supposedly a "select" ShuGuang) 274b from thetubestore. Not sure if it improves the sound of my small single ended amp, but it sounds great and the tube simply looks cool so that makes me feel better about the whole thing.
jl1ny's avatar
jl1ny OP
419 posts
 
I reached out to Upscale and their response was: “I cannot give you an endorsement or recommend it, but it does say it is an equivalent”.

Im curious to see the performance stats of the WE274B compared to 5AR4.
atmasphere's avatar
atmasphere
12,149 posts
 
If the voltage drop is different it can affect the sound. %AR4s tend to be about 50 volts with a light load. The unit will sound perkier with the higher voltage. You could have the unit set up with HEXFRED rectifiers and be done with the whole thing :)
jl1ny's avatar
jl1ny OP
419 posts
 
@atmasphere Thank you for the science lesson! Fascinating stuff 🤯
jjss49's avatar
jjss49
6,612 posts
 
@jl1ny

not to be a killjoy in your case - but if you are going to tube roll to better the sound of the your system, do it with input tubes - spending $ to roll rectifiers are barking up the wrong tree

https://www.primaluna-usa.com/tube-rolling
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