That's funny. They're like that with the four 7591's of my 800C for sure. Addicting as all get out. Soon you're spiralling into sonic excess. I've been there. But I've actually found that if you're away from them for a little while for whatever reason, they're a whole lot better when you come back. Moderation is the key to life.
Where can I find a pair of LED power meters like that, something that I can run between my Fisher and speakers? I ask because my Fisher 800C has that volume knob/power switch thing, and it would make it much easier to get the two channels zero'd out. I'm pretty-good at doing it by ear at this point, but a pair of meters with a large, LED-type display would make it so much easier because I can just dial them in equal to each other. Wharfedales are especially-sensitive to placement and so many other things, and proper channel balance is one of them. Some meters like those would really help with that.
You're so right about the quality of the upstream gear though. Very-true based on my experience and what I've read and heard from other Wharfedale owners. I noticed my W90's frequency response got flatter over time as I made certain upgrades, and now they are surprisingly-bump/shoutiness-free. One of my reference/test songs is Isaac Hayes' "Walk On By", and his lead vocal on that song has LOTS of pitch frustrations that really put a pair of speakers to the test, especially in the lower mids, and it sounds perfect now. More-importantly, the sound has an authenticity to it. Wharfedale made one hell of a midwoofer back in the day. Those 5" midwoofer pairs in the W90's were impedance-matched, same as the tweeters (Certainly necessary with a twin type of design like that). The W90 is sort of like a front-firing version of their older designs, which had the woofer section and the mid/tweeter sections totally-isolated from each other. I really dig the free-air-mounted approach they used on all their alnico tweeters and upper-midwoofers. The W70 is part of that old Wharfedale lineage as well. That period from '55-'63 is my favorite. After Raymond Cooke left, I think Gilbert Briggs may have lost his drive, his focus as far as the company was concerned, or perhaps he was just really busy. He decided around '63 that he wanted to retire from running the day to operations and concentrate on Wharfedale's publishing dept. (as he was already over 70 years old at that point), but the lack of a suitable replacement kept him from actually doing so until February of '65, thankfully. But Wharfedale was quite the company back in the late '50's and early '60's, with a string of legendary models.
The STR6120 is ftc rated at 50 watts per channel. I do Inot use anything like that power. I have a RS led peak reading meter I connected to my Sherwood to see what power levels I was feeding into my speakers and my average power is .0004 watts, it does have an indicator for that level. At that level the max power on peaks is only about a half watt. This is my average listening level so these speakers as well as my Klipsch are great examples of where you want an amp whose 1st watt is of the highest quality. The little STR6045 with its 18 ftc watts is more than sufficient and also sounds good on them.
If I were to experiment with amps and especially tubes, I would go down theater of getting the Sherwood S5000 that used 6bq5 and have Don Sachs or Mike Samna work their magic on it. The guys who have had them redo the Sherwood amps and also had some pretty decent high end gear have said these reworked amps that were already some of the best in their class at anytime were taken to a whole other level. I had the later S5000II that used 7591s and put out 26 watts and can attest the Sherwoods are up there with the best from any company. I think the S-E and 300b low power crowd might like them. At my listening levels these put out more than enough power.
The tube Sherwood would be the most likely path as I love my S9500c on them and it has virtually the same voicing as the S5000II. It is because of this I actually have refrained from going to the S5000II. My wife who knows I was missing the S5000II before getting the S9500c even recently suggested I get one and have it gone over if it will make me happy even given my condition. I have had the W70s off the S9500c for just a few days because of the little together and it is like going through withdrawal. Tomorrow I will rectify this and get a high.