This is utter shite:
Oh and: tubes only? First, flush out your headgear. Then, go listen to them.
I know you have tubes, but Zu’s only exist as a compromise for people with tubes, focusing on easy loads and that’s it.You know nothing of Zu. What you hear with Zu is a full range speaker, sans crossovers. Pure tone. If that kind of musical reality hurts your ears, re-examine what you're listening to every day.
Poor imaging/soundstage, poor vertical dispersion, and the treble is “loose”.
Oh and: tubes only? First, flush out your headgear. Then, go listen to them.