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

OK i got it. But my next question is: how loud can i turn a 92db+ speaker with 160WPC on class A if im gonna change my order from X600.5 to XA160.5. I mean how many db i will have at max volume.

160watts into a 92db efficient speaker should reach 114db .

Tmsorosk:

The impedance of my speakers is 4 ohms. So this means the XA160.5 will double the watts. So this will means over 320 WPC. That will result in even higher volume. I think over 114 db. Something like 117-118 db...

I suspect the XA160.5 will have more than enough power, and is superior to the X600.5 (which I owned). The extra class A power provides the ability to play music more cleanly at a high volume. The remarkable thing about extra class A is the control at climaxes, with preservation of the soundstage. If the X600.5 can play louder, it will sound more harsh and congested, and the soundstage will collapse.

You may need to be open to try different preamps.

It sounds like you intend to listen at very high volumes. The Strads can go loud, but you're talking about volumes well in excess of 110 db. You should talk to Sumiko (assuming that you live in the U.S.) or Sonus Faber to determine whether the drivers and crossover will hold up if played frequently at those kind of volumes. I ran Ebens which use Audio Technology midrange drivers like the Strads and they do not handle power as well as a lot of other drivers (in fact, other speakers that use Audio Technology drivers, e.g., Verity, Peak Consult, Rockport, are not known to be rock and roll speakers). For those kinds of volumes, I again ask why you are not using something like big Wilsons or horns.