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Pass Labs Xa60.8 Class A or should it be called class A/B?

I'm looking at possibly purchasing the Pass Labs Xa60.8, but am puzzled by one of its specifications.  One reviewer stated that "The XA60.8 doesn’t leave pure Class A until it reaches 122 peak watts. Then it moves into Class AB for unheard of headroom for a 60-watt amp".  I've confirmed this headroom is on the specification sheet, but if the amp actually can transition into A/B, shouldn't it really be called class A/B?  Also, I'm confused as to if this headroom is available as continuous watts or just peak.  Can anyone clarify?
dfairc777a

Showing 4 responses by dfairc777a

dfairc777a OP
60 posts
 
I’m assuming that all the output above 122 watts (at least for 8 Ohms) is class B. Makes sense and shows tons of headroom. I can’t wait to get a set of these.
dfairc777a OP
60 posts
 
Yeah, I read that too and understand that it's pure class A, but what's this transition to AB thing?  Do all class A amps have a peak transition to AB point or is this unique to Pass?
dfairc777a OP
60 posts
 
Indeed they are impressive.  I'm really impressed by the entire XA line, but as far as I understand, all AB amps run at some point in class A and then transition. Yes, most transition way less than 122 Watts, but I'm still confused as how a class A amp can leave class A and still be called a class A amp (Unless that's the way they all work). 
dfairc777a OP
60 posts
 
Thanks everyone that answered my questions.  I didn't mean this as a bash against Pass, rather I was just curious as to how this all works. As I said in my original question, I'm probably going to purchase the XA60.8 so no worries at all about them doing something sinister.  
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