Sonus Faber Stradivari amp: X600.5 or X1000.5 ?

Rtn1:

A few days ago i listened on my system the X350.5 and pushed the ARC REF3 to 60-65 and it was very loud. The amp was in perfect control of the speakers without any distortion or compression. The metter of X350.5 was over the half.

Johnb30,
I asked Kent at Pass about the XA100.5 versus the X350.5 driving a difficult load. He told me that in listening tests, the panel preferred the XA.5 and mentioned sonics but also its ability to control low frequencies and low impedances speakers. My speakers are a 4 ohm load and only 86dB efficient, so I switched from the XA100.5 to the XA160.5. With your speakers, you should have no trouble with either, IMO. I suggest you talk to Pass Labs and then demo a pair from RENO HIFI or a local dealer to be sure before you buy.

Ive just ordered a pair of XA160.5. In max one month it should be here. Thanks for all advices and i hope i will be very happy with my new pair of amps.
Thanks.

Ive just received the pair of XA160.5 yesterday. The sound is very good but it still needs some break in time. Does anyone knows how long it takes for XA160.5 for full break in ?

Congrats. I still remember that the magic began after 5 days. Seemed rather stable after 7 days of continuous play. Big, open, effortless is what you'll hear with the break-in. They probably sound closed and slightly raw right now. Good, but not quite right.

To this day, I cannot tell a difference from powering out of standby vs. the end of the day of listening. This is suprising because my system is ultra sensitive to the slightest pertubation. The X600.5 needed 4-6 hours of power before they started to congeal.