PrimaLuna EVO 400 v Cary SLI-100

I had a pair of Primaluna EVO 400's for about six months running as monoblocks. The stock tubes left a lot to be desired and a change to KT88 power tubes and vintage Cifte 12AU7's helped a good bit. However, they never really gave me that tube sound "wow" soundstage I had experienced with my old Cary 6 Packs from long ago. I sold off the EVO's and moved on to a pair of CJ LP275M's. Those are my keepers.

you can give a try our LM-219IA PLUS 

i currently have the evo 400 tube preamp and amp; both great choices; punch way above their weight class and have great technology built in....i have run them with my hersey 3 and loved it...75 watts is more than you’ll ever need to drive that speaker....and easy to tube roll with the evo 400 also...i used the same set up to power my AK6 Klipshorns and they sounded incredible as well; however albeit NOT reference quality, but still very good......both sets of those speakers are now in storage and I am running Wilson Audio SashaV with the Prima Luna gear....and this weekend, will start with mono blocks....as i just purchased another Prima Luna EVO 400 tube amp.....until I can get the Audio Research 330M’s, this will do ok...i’d say with both your speaker and amplifier choice, you are getting HUGE value for your money....way above what you spent.....you are toying with $20K performance in a much better valued system...Go For It....oh, and btw, I have had the 400 amp and preamp for four years now; only have about 120 hours total tube time on them but they sound great; only rolled a set of Tung Sol's through the amp and it did give me more sound stage....have fun with it...no system is ever and "end all to be all" system....it's the nature of our hobby and our addiction....bigger and better...always chase the dream....one can be content for only a period of time....live a little!

Another recommendation of the Dennis Had Inspire products. For much less cost you can acquire a used Fire Bottle amplifier and an Inspire preamplifier. All Dennis Had products are each hand wired and soldered. It’s the best of the best way to design and produce any audio product.

10-12 watts of power is far more than you need to operate your Heresy’s. Check out the audio forum audioaficionado.org for nearly 800 pages of comments from Dennis Had’s Inspire product owners.

@mattsca 

I owned an Audio Research GSi 75 a few years ago.  It is a fantastic piece with phono and DAC standard on all units.  I needed more power as I have Wilson Audio that are a bit power hungry.  There is one on USAM now for $6000.