Ok, amplifiers are all the same 
5W into 90dB speakers with a flat impedance response should be fine (don’t think any really exist though)
The @sjs 300B amp I had would drive the 90dB Snell K’s to a good level and that was an 8 Watt amp but I think the Snells are a fairly benign load.
Yes, that’s completely what I said. 
I never said a “real 5W” either.
I just don’t think that the Pass has the right impedance for most speakers. I could be wrong. I would also expect that the old 6W 6B4G monos that I had would be fine with Hecos.
So… imaginary 5W?
Your 6B4 will likely have an out impdance of 3 Ohms or so (assuming zero feedback type circuit). I’d imagine they’re a very poor match.
A power rating must be specified into an impedance. (e.g. 5W, 5Ohms to keep the maths below simple). Most speakers are 8 Ohms, so this is implicit in HiFi amp ratings.
So, assuming 5W/5Ohms rating, if the load impedance drops to say 2.5 Ohms, the amp can do one of two things:
- Supply the current - Now it is a 10W into 2.5 Ohms amplifier. (i.e. no longer operating a 5W amplifier). This is the behaviour of a voltage source.
- Current limit - so now it can’t sustain the voltage into the lower impedance. A 5W into 5 Ohms amp. needs to supply 1A (P=I.R from Ohm’s law). If the impedance drops to 2.5 Ohm, then the amp can only sustain 2.5V (V=I.R from Ohm’s law). This is now operating as 2.5W amplifier. (And like a current source)
Real world behaviour is somewhat more complex and somewhere in between the two and complicated by reactive loads, albeit everything has to obey Ohm’s law, just that the application of it is more complex.
In neither case is the amp behaving as a real 5W amplifier - there’s no such thing, really, the 5W rating is shorthand for an amplifier capable of supplying the voltage and current required to drive 5W into 8 Ohms (as a nominal speaker impedance).
What it sounds like you’re suggesting (in bullshit audiophile speak) is that the 1 is prefereable. Yes, maybe, albeit it will still be volume limited.
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Why are you so bothered about the amp being Class A?
Iirc Nick (myrman) had a pair of Celan 300’s and ran them for a long time with an Audio Innovations Alto amp, and they sounded lovely with great synergy. The Alto can be bought dirt cheap.
Class A is best.
About to be replaced by the Government’s new 1-9 grading system.
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Although the ACA seems more suited to P levels.
Too many spelling mistakes to be bothered to correct 
Oh, but I corrected your “Quote” 
My Triangles were nominally 93dB / 8 Ohms but made an Audion 12 Watter fall-over and squeak - something which illustrates the point I believe Adam was trying to make: plenty of Amps are claimed to make a particular output - but this is usually into a simple load when fed with a simple distortion-free test signal, and on the bench may even do so, but most speakers don’t present simple loads, and music is rarely simple, and not always distortion-free.
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Your memory is better than mine. Feels like a lifetime ago 
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Yeah that was my point. Audion amps are always far too light, which is a dead giveaway.
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I love class A’s you can have a lot of fun with them, wouldn’t recommend driving anything while using them and you have to know when to reign them in a bit or things can blow up… wait…
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