Just a slight update, not sure how to explain this, using Lamm 4 ohms tab instead of the 8 ohms tab, Q3 is not quite as dark as before. Usher impedance is 8 ohms so I never tried 4 ohms tab with it. On the other hand, string seems to have more sparkle with 8 ohms mode while 4 ohms is more creamy, a bit softer. The speakers are really hyperdetail but in an absolutely non fatiguing way. The first day, I started listening at about 2.30pm and did not turn the stereo off until 10 at night. This is how easy and non fatiquing Q3 is to listen to. Perhaps Lamm is also helping here quite a bit as well.