From another forum
"I've heard three different Lampis (4, and two Big 5s I believe) via a variety of Schiit or EC amps, and they seem to be all over the place. None of them sounded exactly the same. It irks me that there are so many models, making straight comparisons impossible, i.e. "which Lampi?" Then there's the issue of tube rolling - there are a lot of options and tubes to roll inside.
Supposedly the OR5 helps tremendously, but I have not heard a Lampi with an OR5. One thing I feel pretty confident saying is that the analog tube section is fantastic: resolving, clear, immediate without bloat or tooby-ness. Unfortunately, this puts on spotlight on the USB receiver and DAC circuitry which sounded mediocre or pretty darn good but with showstopper type warts (slight treble digititus or grating stridency.)
As things stand, I can not recommend the 4 or the Big 5 to friends, unless they are the type that wouldn't mind spending an additional X amount of tubes, tweaking with caps, etc. You could be just as well off buying a cheapo DCX2496, wiring in a boutique clock board, and connecting the output directly from the DAC chips to a tube amp like the BA. There have been four Lampis on sale (4, 5, 6, and 7) for quite a while now on the 'gon.
Ears I trust say the Big 7 is good, but we are getting into five figures now. "