In past years, we sometimes modified preamps for customers who owned other brands. We sometimes heard this request: “Can you please make it stop eating tubes?”
This refers to the fact that some other brands run their tubes hard, which causes them to fail rather quickly. Designers sometimes run tubes hard because of some measurement outcome they want to achieve, or looking for better sound quality. One customer told us that his very popular name-brand preamp was going through pairs of tubes as often as every 3 months, and he never had a pair last longer than 8 months. One pair only lasted 6 weeks. Ouch.
Easy. Backert Labs preamps are easy on your tubes because we do not “run them hard”. When people talk about running tubes hard, they mean running a high voltage or a high current through the tubes. Or both. We are not aware of any other manufacturer that runs tubes more gently than we do. Please note that this is not our ultimate pursuit — our first goal is the finest sound quality. It just so happens that when we employ our gain stage with a pair of 12au7 tubes (or the 12at7 tubes in our Rhumba Xphono), the voltage and current settings that provide the greatest linearity and most faithful amplification are very, very gentle on the tubes. It is a happy coincidence.
