Originally Posted By: Quattro Pete
Well, I guess without access to the particular speakers' impedance-frequency curves, it's really impossible to answer my original question.
As for the amp, it's a Class D amp designed to handle 2 Ohm loads, at least on paper...
Not to make this any harder, but the impedance curve is just one factor in the matching equation. Other factors, such as the speaker's efficiency (SPL), the listening area volume, the loudness levels anticipated or desired, and even the music type favored, all play a role in speaker to amp matching.
Every amplifier is potentially capable of driving a 2 ohm (or less) driver load. The real question is how many amps is the speaker asking for at that impedance to produce the intended frequency at the SPLs required for a balanced response at desired loudness levels. If it's an old K-Horn, a Walkman might do the job. But some others might require an amp that takes two guys to carry. There is no substitute for iron and electrolytic paste when it comes to power supply reserves.
And then once you add the timbral element (or voicing as some like to call it in the hobby), the good matching of speaker to amplifier becomes a bit of an art. No audio component is perfect, or perfectly "neutral", and all have what some call a "voice" or timbral/tonal signature. Some amps and speakers are warmish or "musical", others cooler or "transparent" sounding. The same goes for front end components, and it can even devolve into discrete parts inside each box. Right down to the resistors and caps used. None is bad, per se, and the skill is in balancing each system piece against the others to reach the result you are after. And you don't have to spend megathousands to reach a very nice result. It's a bit like cooking: all one ingredient usually doesn't taste as good ;a dash of this and a pinch of that all contribute to a good dish.
For instance, a larger Thiel usually needs a high current (and very high quality) SS amp on the warmer side to do its best (getting sufficient grunt in tubes can get really expensive with them), while someone fond of vintage Tannoys will almost always lean towards lower powered, but very tonally nuanced, bottles. Both will be very happy with the results with a thoughtful pairing. Some folks are bass freaks. Others (like me) value vocals and place a premium on the midrange. Others love a clear detailed top end. That also plays a part in system building. But the most important ELECTRICAL match in the system is that between power amp and speaker driver. A lot of careful front end matching can be quickly undone by a speaker that is improperly driven by the wrong amp. Many people who complain about Thiels sounding "cold" fall into this category, when the paired amp is unable to deliver sufficient clean current at the bottom octave and the relative SPLs at those frequencies sag, throwing off the tonal balance.
Working in a vacuum with your OP, a "6 ohm" speaker often draws more "power" than an "8 ohm" one. But power is not everything. Good power is expensive, and sometimes aural compromises are made elsewhere even in the best designs to get more of it. Buy only what you need. As others have said, the first watt is the most important one, and there is a wide variation in quality in that first watt among manufacturers.
A class D amp can sound decent as long as you don't drive it too hard. But in SS, nothing sounds as good (or runs as hot) as pure class A. Ask any old Threshold owner. But I'll still take my vintage tubes for tonal nirvana, thank you.
Playing with the equipment is a large part of the hobby. As long as it does not supplant the ultimate goal of enjoying the music and artists (so many get trapped into chronically listening to their equipment - and forget about the music itself), it can be very enjoyable.
And then there are the measurable vs. the audible (but unmeasurable) religious wars to contend with. After over 40 years in the hobby, that is all best ignored with a quiet smile.
More than you wanted or likely needed to hear. I guess we'll leave it at that.
There are some good dedicated Internet fora to cover this further if you desire, such as Audiokarma and Audio Asylum.