What tube amp for Harbeth 40.1

It all depends on the type of sound you prefer: softer, warmer, less dynamic sound, or crisp, clear, dynamic sound.

If you like the sound of the JBL’s you noted, you’re not going to get that with any Harbeth driven by a tube amp. The closest you may get is with a tube hybrid like the MA252 or MA352 - which is not really a tube amp.

In fact, it’s even hard to obtain that sound with any Harbeth driven by SS amps.

The JBL’s have a "studio monitor" sound - more like ATC’s, Ocean Way’s, Proac’s.

The closest Harbeths get to that type of sound is with powerful, neutral SS amps like Bryston, Benchmark, ATI... or Hegel.

I have the M30.1’s and the M40.2’s - and - I wanted the same sound as you, having heard the JBL 4700’s - both crystal clear clarity and dynamics, but with a holographic sound - which is difficult to attain with Harbeths. I tried ARC Ref 5SE and ARC Ref 150SE in combo, and didn’t get close to that sound.

I then got the Hegel H590 - and "voila" - I now have it... or... as close as I’m going to get with Harbeths, which have a bit of a sound like they’re covered with a warm blanket - heavy on the bass and mids, with less clarity in the upper mids and highs - until they’re awakened with a powerful, neutral amp. Until I got the H590, I was ready to sell the Harbeths and move on.

Even with the H590, they don’t quite have the holographic sound of Maggies, or quite the crystal clear clarity and dynamics of JBL’s... but... they do have much of that sound... and... with a very rich, musical sound a lot like a live performance. In some respects, the crystal clear clarity of studio monitors and JBL’s is too pure for the sound of a live performance - by design to meet the requirements of studio engineers. The Harbeths, driven properly, have more of a live performance sound.

But... if you must try tubes... I’d try the MA352 hybrid, or the Atma-sphere OTL M60’s with AutoFormers, or the Zotl LTA - but, almost anything in your price range will disappoint you - given your stated preferences. You might try the combination of a tube DAC (the MHDT), a tube preamp, and a powerful, neutral SS amp - like a Bryston, or Parasound Halo.

But... in the end... given your preferences... I’ll bet you end up with something like the Hegal H300, H360, H390, or H590 - which is what Alan Shaw of Harbeth prefers, suggests and shows his speakers with.

That is... if... you keep your Harbeths.

Given your preferences - if you want to try tubes, you might find you prefer the sound of the Proac D2's driven by the Line Magnetic 518i, or similar.  That combination is closer to what you describe you prefer, especially in an apartment or condo - unless you're prepared to drive the Harbeths with a powerful SS amp.

excellent comments bassdude!

i keep my harbeths, proacs and atc's for exactly that lovely contrast in presentation

@bassdude
thank you very much for your comments.  Although I already bought a McIntosh 275, I always tempted to buy a SS with greater than 200wpc.  I have an old Adcom and it sounds quite good on the Harbeth.  Would there be any good (vintage) SS amp in $1500 range that you would recommend?  Such as old Luxman, Sansui, Onkyo ... etc?

The Harbeth 40.2, the Annie, and 40.3XD have slightly higher sensitivity than the 40.1, 86db vs. 84db, but those newer models have a much higher impedance curve. The curve on the 40.2 stays above 8 ohms throughout almost the entire frequency range even staying around 10-12 ohms which should make it an easier load to drive.  That's why tubes above 50 watts sound glorious.