For efficient speakers, how much difference does an amp really make?

@scothurwitz, what do you mean “Pass Labs little xa30.8”?  That sucker weighs 93 lbs!  But I do agree, it’s a great amp.

Sadly, I’m an audiophile on a budget.

In fact, my entire system...preamp, monoblock power amps, CD transport, turntable and speakers didn’t cost as much as the Pass XA30.8 amp does all by itself. Maybe one day....

I have many speakers, but currently using Zu Dirty Weekends, which are like 97dB/w with a 12ohm impedance.  I've tried 3 different amps on it.  My 120wpc Rotel sounded terrible on them, but my Bryson 4B-ST (reCapped) sounds great.  And...  with really dynamic material, I will blink the clip lights on this 250 wpc amp!  Now....into 12 ohms, it's really only about 165 watts, but the Zu's will utilize the full voltage swing of this big amp.  The Zu's are clearly an easy load, yet i clearly hear differences with each of my amps.  I have a newer Byston that I'm looking forward to trying on them that might sound even better....... or not?  

Hey doni,

My comment on the Pass Labs "little" 30 wpc xa30.8 was just referring to the watts per channel. The watts per channel on a spec sheet really doesn't mean much and certainly doesn't tell you what the amp sounds like.

Yes, you are correct, there is a reason it weighs 93 (88 net) lbs, Nelson Pass understands the importance of and knows how to build a well made power supply. That "little" amp is ALL power supply. His newer xa25 is also supposed to be great amp (if you don't want or need balanced). There's a reviewer for "The Audio Beatnick" online magazine that owns both of those amps and he feels the xa25 sounds even better (in certain area) than the xa30.8.  

I had that xa30.8 amp connected to a pair of Magnepan 3.7i's WITH a pair of their DWM woofers wired in parallel (talk about a difficult load) which presents a constant 2 ohm load to the amp and that amp handled it without even breaking a sweat! I ran that system like that for 3 years and never once had a problem with it. It was one of the most musical sounding setups I have ever owned.

Scot 

Efficiency and easy load are not the same.  
Efficiency means things get louder faster. 
An easy load means all frequencies get handled similarly and lesser difference to be expected  from amp to amp other than how loud things go.