thunda1216 said:preamp tubes are going to be a matter of taste; I run NOS in V1-V4. To my ears, the Shuguang 5AR4 sounds really good, but they don't last as long as NOS. I'm currently running a GE, it's lasted for 8 years now. Before that, I went through 2 Shuguangs in 4 years. I recently tried a Sovtek and it sounded OK but I have no idea regarding the longevity.