Your tube amp related Harbeth experience.

Tried SHL5+ with PL Dialogue Premium HP and also with McIntosh 275(s).  Awful.  They sounded great with a vintage Sony TA-N77ES, but absolutely stunning with a Pass XA-30.8.  

@arafiq

My Harbeth SHL5+ can sound a bit on the bright side with SS amplification. I tried them with Luxman 590AXII, and as good as the pairing was it did tend to sound a little bright on some recordings. Moving to a tube amp -- Audio Hungary Qualiton a50i, took care of that issue.

if i am recalling correctly from early on when you started posting here, you were/are dealing with a listening room with lots of glass and other hard surfaces, so if this is still the case i am not surprised you need to tame the highs of the super 5s... in general though, i would say most owners of super 5’s would not have that issue, in fact most are trying to get the speakers to have a little more top end energy and marginally improve the jump factor of the speaker

just another real life example of how forums and their advice can only get one so far... folks who want the ideal sound have to work on it in their own space and situation

I had the Harbeth C7s, and I tried several different integrated amps with them.  The only tube integrated that came close to driving them to my liking was the Primaluna Dialogue HP with KT150s.  However, I far preferred a Bryston B100 solid state integrated amp to any of the tubed models. 

@jjss49 -- I have two system setups in my house. The one in the home office has a glass door plus the usual home office stuff (desk, bookshelves, etc.). However, the SHL5+ are, and always have been, in the media room which has no windows, has a carpet plus rug, and is nicely treated with GIK panels. I spent quite a bit of time and effort in treating that room and placement options, and I can assure you it was not the reason.

If you do a search on audiogon for keywords 'harbeth' and 'bright', you will see a number of folks who have reported similar findings as mine. But keep in mind that it is all relative. What I call bright might be zesty and fun for someone else. Either way, the Qualiton took care of that slight bit of brightness and thinness I experienced with Luxman, but without losing any details or resolution.

+1 on Harbeths with Rogue Audio Cronus Magnum III.  I have SHL5+ and love the combination.  Alan Shaw is right on at least one point - to get good dynamics out of these they need a decent amount of power.  Thus, the Rogue, with 100 W.   Of course, you will get sloppy bass and insufficient dynamics if you try to power them with 15W.   Don't be fooled by the Rogue's low-ish price.  The amps are great.  Agree that Rogue tube amps sound much better than many people give them credit for.