Tube amps vs solid state for large speakers

I haven't heard the AES Sixpacs but had an AES AE-25 Superamp, the DJH signature version. Great sound for the money, not the last word in tube warmth but more on the neutral side and good bass. The fun thing about the Superamp was trying different output tubes. I ended up trying over 20 types of tubes, each of which significantly affected the sound. You might be able to do this also with the Sixpacs, which have more power output and probably better bass.

I would think with those specs and assuming a smooth impedance curve that 60 tube watts would be plenty of power to drive them as loud as I would ever want to hear them. That of course opens up a much wider selection of choices - though I could hardly recommend a better value with great sound than the Music Reference RM9MKII previously mentioned, or the Quicksilver V4s if you want a little, tiny bit more margin of error over 60 watts on ultimate volume. I run my Merlin VSMs (89db, smooth 8ohm) with 30 watts integrated tube - no volume issues.

Prima Luna Prologue monos with KT-88s.Auto-bias,making tube rolling much easier.

With due respect to many of the contributors to this thread, a lot of the information here reflects a misunderstanding of tube amps and what is important in a tube amp.

The ability of a tube amp to properly drive speakers is not so much determined by its wattage rating, but rather, by the quality of its output transformers (which convert voltage to current, current being needed to drive speakers featuring low impedences in the bass frequencies) and the size of its power supplies. It is generally easy to determine whether a given tube amp has quality transformers and power supplies: if the amp is heavy as hell and expensive as hell, you generally have a fine tube amp, as high-quality output transformers are both extremely heavy and costly (power supplies are likewise heavier the bigger they are). To make a rough analogy, a high-powered tube amp with mediocre output transformers is like a high-horsepower engine mated to a bad transmission -- if you can't get the power to the wheels and to the road, it doesn't matter how many horses you have. There are some very well known, supposedly "high-powered" tube amps out there that cannot drive tough loads because mediocre output transformers were used.

Generally speaking, it is very hard to find a tube amp that retails for less than say, $15k, that will properly drive dynamic-driver, low-impedence speakers, and $20k+ is more typical. In my experience, the CAT amps are by far the best in this regard, my VAC Renaissance amps being somewhat less good but still very good.

In my opinion, unless you are willing to commit real money to tube amplification, you're usually better off running a good solid-state amp.

I don't know, my $AU3k Melody tube amp which is 40wpc drives my big Osborn Epitome speakers (90db) to ear bleeding volumes with control and it sounds great. I agree you need good transformers to make a good valve amp and power ratings are not a great guide but there are some good amps out there at reasonable prices.

DS