Wo~I have just bought a wonderful DIY Grounded Grid Preamp from Analogmetric!! It is absolutely silent in background. The spacial feelings and level of human sound is definitely clear and it is really outstanding. When I first time see this item, the price was very cheap and I suspected its performance by its cheap price. However, I felt it is my best and most reasonable DIY preamp I bought before. Really worth to try, recommended to all.