The Berkeley upgrade is Substantial, not subtle. You will be pleased. I have no cabling issue. If I drive my Atma Sphere MA-1 amps, the sound is both much more dynamic and focused using the Ayre preamp in the chain. So I am not universally bemoaning the use of a preamp. Preamps have merit. I'm just saying that I prefer the sound of the Berkeley Reference 2 DAC driving my Ayre MX-R Twenties directly, with no preamp. I have two runs of balanced Synergistic Element CTS, so its a piece of cake to A\B the sound with or without a preamp. With the Ayre preamp in the chain, the sound is more focused, so I prefer the more airy Synergistic presentation. With the Berkeley driving the Ayre amps directly, I prefer a shade more focus, and run Audioquest WEL. I hear more details, and more realistic harmonics around those details without the preamp, in this case.