If you decide to stay with Harbeths - get yourself a powerful SS. Thats when the magic starts.....listen to Alan - he knows his stuff. I drive my 40.2 with two 400W simaudio mono blocks.....If you want something nice get a Hegel H190/H390/H590 (finances dependent) - Alan used H390 to voice the Anniversary and XD line...
Here is my analogy of using tubes with Harbeths - you buy yourself BMW M8 with 4.4-liter BMW M TwinPower Turbo V-8 with 600 HP and you decide to put 87 Octane gasoline when the designer C L E A R L Y specifies in the manual to put at least 93 Octane.
All your friends are wowed by $140K sport tuned car waiting to see what it can really do on the road - instead, you tell everybody that you like the romantic lack of engine power when cheapest gasoline is used.....
Yes, you will be able to drive that car in the city traffic with 25MPH speed limit and if that is all the driving you do - fine, but why the hell did you buy the sport car?
One day you decide to go and do some highway driving - car has absolutely no power and engine light turns itself on.....now you confused! Upon return home, you email BMW with questions regarding your machine's lack of power.
Meanwhile, you go on several car forums complaining that the specification says 600HP so why there is no passing power.......Several technicians from BMW calls you to explain the reason of your frustration but you are telling them that the car just drive better on 87 Octanes fuel......After several months of your persistence, you decided to sell the car (loosing at least 60-70% of the purchasing price).
Anytime somebody mention BMW, you look the other way expressing your negative opinion and disappointment on multiple car forums....
I have seen MANY scenarios like that especially with HL5s and 40s.....severely underpowered amplification was used and users left disappointed and unhappy. I will not even discuss the room acoustics and other important factors.....