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


Hello,

I want to know which power amp is better for my new speakers (Sonus Faber Stradivari) combined with ARC REF3. Ive just listened a few days ago the X350.5 and i loved it so much. Right now i have a pair of MC-501 but i'm a little dissapointed of them when i try to listen to some complex music like rock and others. Is X1000.5 a good choice for it or X600.5? The X1000.5 have 2000 wats in 4ohms?
Anyone listened to both of them. Let me know.

Thanks.
johnb30
Johnb30:

That's not the way it works. Again, every time there is a fortissimo passage, the speakers can draw far in excess of 80 or 160 watts, and the amp operates in Class AB. For pop or orchestral played at "normal" volumes, this happens all the time, which means that crossover distortion is always an issue. If you are listening to chamber music at 75 decibels at the listening chair, this won't happen, but it happens all the time with pop / rock / orchestral / big band jazz, etc. Again, if it wasn't an issue, amp manufacturers would not bother to make full Class A-biased amps, which are not easy to own (enormous heat and tons of electricity - mine draws 1,400 watts at all times and gets HOT).

I suggest that you make a judgment call as to just how much loud music you listen to. John Atkinson estimated the Strad's sensitivity at 93 db., which means that it is highly efficient - you do not need a high wattage amp to make such speakers go loud, just a well-built amp (i.e., stiff power supplies) that can deliver current (it drops to 3.3 Ohms in the bass). If you intend to listen to a lot of loud music, however, why not buy a loud music speaker, for example, big Wilsons? In any event, unless you do most of your listening at really loud volume, a high-quality 150 watt/channel amp, especially one that does not use global feedback, should make you happier in the long run.
Don't get so hung up on "watt" ratings. I've read where XA60.5s were compared to X250.5s...and were preferred.

How can that be? A lowly "60 WPC" class A amp slugging it out with a "250 WPC" class A/B and coming out on top?

It's telling that XA100.5s can be had for about the same money as the X600.5s.

The XA.5 amps are just in a different league.

And I own X260.5 monos and XA60.5 monos. I run the XA60.5s daily. I really like the X260.5s, but they don't outpace the XA60.5s, and I like the sound of the XA.5s better.

Think on that: I'm not sure how much "Class A" watts the X260.5s are supposed to deliver, but the "little" XA60.5s are more than a match, even at high volume levels.

If I had the funds, I'd have all XA.5s. Whatever the class A rating of the X.5, I wouldn't care. A "smaller" rated XA.5 will more than compensate. I'd really like to compare a pair of X600.5s and a pair of XA160.5s...I know where my money would be.

Also, the XA and XA.5 amps are different machines. Try not to get highjacked by any comments about XA amps and their relative performance.
How can that be? A lowly "60 WPC" class A amp slugging it out with a "250 WPC" class A/B and coming out on top?

Pass haevily underrates the output power of all their XA series amps. The lil XA-30.5 was measured in Stereophile, and turned out to put down over 130W @ 8 Ohms vs advertised 30W.

See LINK
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.