Great Tube/SS Amp for Proac D40R ?

Great sounding speaker. I particularly like how well the ribbon integrates with the rest of the drivers--something quite rare with this type of driver.

I have heard these speakers with some fairly low-powered electronics, including the cheaper amps from the Italian company Synthesis. These speakers do not seem to need much power to fill a large room. I would NOT restrict choice to something that delivers 100 watts or more.

These speakers struck me as delivering a fairly rich and complete harmonic structure and are not lean sounding like a lot of modern speakers. This should make them pretty compatible with a wide range of electronics. For solid state, I like the lower-powered offering of Ayre. For tube amps, I would look at Synthesis, AudioSpace, Ayon, Joule, Atmasphere and Conrad Johnson.

I heard these at Arizona HiFi with the Grommes PHI-26 a 1.75wt triode/6 watt pentode amp.

amazing sound and made me wish i had the funds for them

I didn't but did buy the amp.

I have a pair of Quicksilver V-4 amp (KT-77 or EL-34 tubes) driving my Proac Response 2.5. It is a great combination.

I have also heard the Quicksilver V-4 on the D-30R (KT-88 tubes)and I thought that also sounded great. I think Quicksilver is synergistic with Proac speakers. Additionally I have heard them with the Grommes, Leben, and Shindo amps. They sounded very good with all, but I like the additional power of the Quicksilver when you want to crank it up.

Quicksilver V-4. 120 watts into 4 or 8 ohms. The price new is $5595/pair with Tesla KT88s. I run KT-77 tubes in mine. They can use quite a few different tubes. They occasionally show up used on Audiogon.

I've now heard the D40R's with the Ayre K-5xe / V-5xe combo and that was very nice. Very full, neutral, slightly warm sound.
I can see how people are calling Ayre "tubby".
It was missing a touch of lively, pacing (a little soft) for that sort of connection but would overall beat many others.
Hopefully I'll be demoing the new AX-5 and VX-5 soon.

I'm looking into Plinius 103 (don't think I can demo this), Pass labs (not narrowed down a model, hopefully can demo)
I should be able to demo a VTL and Electrocompaniet soon.
I was looking at the Quicksilver V4 but can't demo it. I'll have a better idea of tube after the VTL.

I first heard the D40R's with a 300wpc class A and was blown away in clarity and pacing but missing just a touch of fullness.
From what I've heard so far these speakers "can" sound very nice with good clean lower power but "can" really shine with more.

Audiosean I would be interested to hear what you ended up with as an amp.

I'd also be interested in others experiences with D40R's.

I have just bought a pair and I'm currently using them with a Luxman L505U but I'm looking at other amps as a consideration.

I have the D30R.. I use them with an Ayon Spirit MKIII.. If I had the D40R I'd certainly consider the Ayon Triton..

FYI Proac 's like tubes or pure Class 2 solid state..

You should consider the Quicksilver V-4. I am very happy with this combination, see my system.