When were the best tube amps made?

Every time has good, bad, mediocre.

@erik_squires Funny you mentioned AR from 80's. AR fans will hate me for this, but AR SP9 MkIII  has remained one the WORST sounding components I ever purchased, very bad memories of that one. Hybrid design didn't work for me, SP10 would have been much better choice. This purchase probably around 1984-5.

AR fans will hate me for this, but AR SP9 MkIII  has remained one the WORST sounding components I ever purchased, very bad memories of that one. Hybrid design didn't work for me, SP10 would have been much better choice. This purchase probably around 1984-5.

@sns 

Yeah - have to agree. Some years ago, a few friends and I did a shootout of several preamps. There was an older AR hybrid preamp in the mix, and I believe it was specifically the SP9. Tons of gain. It performed relatively poorly. Couldn't even keep up with the entry level Rogue Metis, much less their 99, and an Athena just blew it all away. It was more on par with the Sonic Frontiers SFL-1, also a hybrid. Those hybrid preamps had a steely edge and sounded lean and unnatural compared to the all-tube preamps. 

But that SP9 has seemingly NOTHING in common with the current Audio Research preamps, which are absolutely wonderful. Still a big fan of the Reference 6 here. AR really upped its game in the current era.

I wonder how much of my opinion of ARC has come from the SP9 and so many who claimed to love it at the time?

I agree that the current ARC line is much better than what I remember from the mid 1980's. 

Weird to me you'd attempt a hybrid preamp. 

I stashed that SP9 in a closet for perhaps a decade, forgot I even had it. Upon rediscovery put it up for sale, sold for asking price in a minute. I see post in forums from time to time, some think that pre something special!

Someone above made a Harley Davidson reference, and it fits well in this discussion. The best tube amps that ever existed are being made today, but they still include the same important electrical physics element, inherent distortion. Currently Harley has to be careful not to engineer out the trademark sound of the past engines just like the makers of tube amps want to make all parts of the amps better with what engineers have learned, but still using the tube design factor. Tube amps are very highly refined today with better transformers and more capability than ever, but just the fact that they are tube amps, and will have ~.5% distortion to start, and this distortion seems to add a harmonic that is pleasing to human ears still makes them desirable and makes the current offerings from all over the cost spectrum alluring to audio lovers. I have no way to state to anyone what the best amp from past or present might be, but I can admit that I'm still interested in a MC275, and even some of the offerings from lower end players such as Monoprice and similar to play with. While I look at some vintage pieces with nostalgia and desire, knowledge and common sense tells me to buy something current with all the improvements.