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

Onemug:

When i'm listening to very very loud it stay at 500W and sometimes at extreme levels go up to 1000W.

Johnb30,

That helps a lot. My feeling is that you would be better served by the 600.5 or go for the 1000.5's if you want. I've had the X's in my house and own 2 XA.5's. The XA's are the better sounding amp but you pay for quality over quantity in their case. That is not to say the X's are bad sounding, they are great but you seem to need the horsepower more.

You might come close to the best of both worlds with the XA200.5's but they will cost you north of 30 grand. As mentioned earlier, the XA.5's put out a lot more than their rated power. You might get 1000 watts from the 200's into your load. Do know this: you are punishing your eardrums at those levels. You will suffer some hearing loss if you do it too long/too often, but they are your ears.

Onemug:

I'm listening at such levels very rare. Almost 90% of the time the speakers are at 10-20watts but sometimes when i'm getting some drinks and want to hit it hard i kick it to 500 watts. This happends like 2-3 times a week no more then 1-2 hours. All the other time i keep it at max 5-10watts. But i still want to be able to play it very loud when i'm in that mood.
And also when i'm watching a movie on my cinema i switch my Strads to my klipsch that are hors with 99db sensitivity and i think this XA160.5 should be enough to play it very loud on that to.

Extreme levels! That's not safe.

If you listen at a lower level, your ears will open after a few minutes. You will actually hear more of the music and deeper into the recording.

The X.5 series is a relatively good value, and can provide brute force. But as Onemug said, you are paying for quantity rather than quality. The XA.5 does the power thing quite well, while also providing finesse and beauty. It comes down to priorities.

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.