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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?
128x128jl1ny
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jl1ny OP
393 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
11,575 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 :)
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jl1ny OP
393 posts
 
@atmasphere Thank you for the science lesson! Fascinating stuff 🤯
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jjss49
6,608 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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jl1ny OP
393 posts
 
@jjss49 I did! replacing the OEM 12AX7/12AU7 with Gold Lion. But I fell down the rectifier rabbit hole when I read about the Philips 5R4GYS. Ima sucker for aesthetics...the WE274B is sexy piece of glass! I figured if I can improve sonics AND have some cool looking glass then why not? 
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