Where do tubes matter most???

The biggest sound difference, tubes vs. SS, will be in the power amp, hands down. Having said that, I do not use tube amps for that very reason: they sound too much like tube amps, and I can't live with that much deviation from neutrality. Tubes are vastly better suited for the impedances seen in electronics, not speakers. This is one of those iron laws of physics that no one can do anything about. The closest I've seen to a real solution to this problem is the Berning ZOTL approach, but that limits your choices quite a bit. In the end, you need to listen for yourself, in your system, with music that you enjoy, and decide. The good thing about tube amps on Audiogon is that you won't lose much resale value if you buy carefully.

If your speakers are moderatly efficient , I prefer all tubes. They add a natural richness and level of realism that many SS components can not approach. Tubes do require a small amount of involvement for biasing , replacing tubes, tube rolling. I think its fun. I reccomend Audio research gear to get you started. Its very reliable and well made. My first ARC piece changed my 30+ years of audiophile experences.The sound is so amazing you will not believe how beautiful the sound can be from tube equiptment is.

They matter the most where the most gain is, which generally is in the preamp (or phono stage, even.). All tube system is the best way to go. reserve SS amps for bass-only use, if at all.

-Ed

I suggest all tube. I use no transistors anywhere in my signal path.

Generally speaking I think that tubes usually impart their characteristics most in amplifiers, and depending on their load it may or may not be for the best of technological reasons. There may be some particular tube amps that are exceptions. While I haven't heard them myself (I very much would like to) the Walcotts may be such an exception. As to whether this imparted characteristic is "nice" is open to debate.