Quote Originally Posted by emack27
OK so would it be fair to say that high efficient speakers sound good with tubes and low efficient speakers sound good with SS?
Actually, there's not a bright line rule on that, but it is more likely that high efficiency speakers will work better with lower watt tube amps. But there are some solid state designs from makers like Pass Labs and Sugden that run totally in class A that work better with high efficiency speakers. These amps are usually rated at 25-30 watts per channel.

When it comes to tubes, I think economics has more to do with this than anything else. You can get a 100wpc solid state amp for around $300 - 500USD that can drive something like a Dynaudio speaker (4 ohm, 84dB) while a 100wpc tube amp that can drive the same speaker might cost 10x more. Most entry-level tube designs are rated at 25-40wpc and need to drive a more efficient speaker. There are big bucks tube amps that can drive just about anything.

Then there are the extreme examples of low powered tube amps such as SET, 300B, and 845 designs that are rated at about 2.5 to 15 wpc. They make really high efficiency speakers for these that are often single driver designs in the 97dB to over 100dB efficiency range.

So, it usually works out the way you stated it, but it's not a rule. I think the rule can be stated more generally, i.e., lower powered amps (whether tube or solid state) sound/work better with more efficient speakers.

In describing sound characteristics I would have to say in my limited experience that tubes do sound smoother and I believe they sound more natural. You don't have to give up detail with tubes. In fact, I've been trying different tubes in my amp recently and I found a pair that really opens up the treble adding more detail and "air" in the high frequencies. Without balance such as midrange detail and bass weight, this would sound "bright". I'm trying to decide whether these tubes have too much treble emphasis but I don't think they are fatiguing. With my old solid state gear, music with lots of treble info like strings would become fatiguing. The best thing to do would be to take some of your favorite recordings to a dealer that carries tube equipment and audition. Interestingly, it seemed that until recently some tube amp manufacturers were trying to make their tube gear sound more like solid state. Find a dealer that carries brands that have the more traditional tube sound like Conrad-Johnson, Cary and Jolida. Heck, if you were going to get a tube amp that sounded like solid state you might as well get a solid state amp from Krell or Bryston.

Anyhow, I got my first home audio tube amp in November of last year. I've enjoyed the music, but I've also had fun learning about tube amps and trying different tubes.