I would think the Audio Research models would be worth looking into. Also Sonic Frontiers. Neither of these makes give you "tube sound" in the sense of soft sounding, they are supposed to be 'accurate' not 'tubey'.
You could try the 'V-12' from Cary, switchable ultralinear/triode and offering a decent amount of power.
Amps of power do exist, but they are VERY expensive. CAT amps, at about 100 watts pure class A( most unbelievable 100 watts I've heard); Atma-sphere has 2 models, MA1 and MA2, rated at 160 and 220 respactively. ARC has very powerful tube offerings. Jadis is a tube amp I have lived with and greatly enjoyed. VTL, Shoreline, are some others. Check used tube amps.
I have a pair of Thiel 3.6's (86 db and 4 ohms) with a pair of Levinson 20.6 100W mono's in a 13 x 24 x 9 room. While waiting for the factory to send upgraded circuit boards, I purchased a pair of Wright-Sound WPA 3.5 SET's for the interim. That's three and a half big ones of power. Bottom line - with the 20.6's a comfortable volume level on the CAT with classical/instrumental/jazz is the "ten-o-clock" position on the volume knob. With the WPA 3.5's the same level was perceived at the "two-o-clock" position. Even orchestral music was reproduced without any strain whatsoever. To say I was surprised is an understatement. But note: most SET output transformers are jumped for 4,8 and 16 ohms. Can't really say what a 6-ohm Z would do.
Wolcott Presence monoblocks should work well also.
If you are looking for great tube sound :
JADIS JA 100/250 (the newest model replace JA 80/200) period.
JADIS JA 80/200, VTL 750 ref, BAT VK150SE, or CARY V12 Mono are my second choice !!
Get rid of your SS right away and you'll find the MUSIC should be !!
Good luck !!
I drive my Kef Ref 4's (91 DB but 4 ohms)with Aranov 9100 monoblocks(110W a side via KT88s). I also have a Classe 301 (300W) that I've A/B against the Classe, and the SS does have a "firmer" bottom end, but not by much, and nothing that a good SS powered sub didn't cure (Rel Stadium). I also tried bimamping with the Classe on the bottom, but I just can't justify a $5K amp doing only woofer duty -- and the increase in improvement was incremental at best. Thus, I've settled on the Aranovs with the sub helping out -- it's not so much the low end, but rather the sub takes some of the worload off the tubes.
The nice part about the Aranovs is that they can be had for under $3K used. And I also found that biwired hi end speakers cables hepled a lot (HT Magic Woofer/Tweeter) --Lorne
Try the Conrad Johnson PREMIER mono-blocks.they should do the trick.Also the MV-100 should suffice too.Nice sound.
Also take a look at the VAC PA100/100..big transformers/ power supply and 2ohm taps. VAC proofs these on some large Thiels, so they have plenty of muscle. More user friendly than ARCs and with NOS tubes sound like an amp costing twice the price.
Atma-sphere MA2 MKII.2 should be perfect. Duke can help you out at AudioKineses - He is the man!
the Sonic Frontiers Power 2 110w stereo or Power 3 220w mono amps for a couple reasons.
If you read the review technical/measurement section in Stereophile (where they earned class A recommendation), you will see John Atkinson say it was one of the few tube power amps he could use to evaluate different loudspeakers.
The reason is low output impedence, which equates to a high damping factor, and flat frequency response even with reactive loads.
They are built like tanks, user friendly, dependable, sound amazing, and are at super prices right now so you can get a new one that has a factory warranty and new tubes for the price of a used lesser amp that may be used, no warranty, and wasted tubes.
No matter what...with electrostats, ribbons, or just speakers that are a pain in the ass, they cruise right through.
You may want to look at the Kora Cosmos monoblocks. These are 100 watts of pure class A power. They are rated to and will drive a load from 2-12 ohms all day long. They have a signal to noise ratio of over 100db and a wide bandwidth. They utilize 8 6AS7, 4 EL84 AND 2 6922'S PER MONOBLOCK!
They are also a great bargain at the moment.
Try a Music Reference RM-9, or RM-200.
Roger's amps are taped out to 2, 4 & 8 Ohms, and have plenty of current.
I am using a modified Music Reference RM9 to drive maggies in a rather large room. I would describe this as being one of the more difficult scenarios for a tube amplifier, but the RM9 is easily up to the challenge. And the best part is it's a steal on the used market.
There is a product called the Zero Autoformer that I recommend you investigate along with your amplifier search. You can find information regarding these at the following link. http://www.condor-connection.org/asog/tweaks/ps/index.html
My speakers are rated as a nominal 8 ohm impedance and benefited dramatically by using the 2X setting of the autoformer.
I do not use any speaker cable, just the Zero's, with my monoblock amplifiers. They are a truly tremendous product.
i have a little tube research 80 watts triode . it has a larger power supply than audio research 600s . it will drive the hales like no tomorrow. where are you ? i will show you.
I own the Tube Research Mono 100's, (Less than 100 watts in Triode pair of KT-88's, I can tell you that they can drive a difficult load easily. You may wish to take Kirk up on his offer.
atma-spheres ,jadis ,vac,wolcot, sonic frontiers, conrad, etc; all these amps are worth a try. they are all damn good amps. i have owned jadis 200 monos ,conrad premier 11 ,12s and 8s, sonic frontiers power 3s. on and on. i would of been happy with any of them if i had not heard tube research. i use to enjoy trading amps preamps etc. now tube research has ended my trading , buying selling . i now trade buy and sell with secondary systems only.