Recently I was fortunate enough to snag 3.7s around the 1st of the year. They were serviced by Rob at Coherent Source before I got them to replace my 3.6es ( loved them). I have not heard the 2.4, but I can say without hesitation that the 3.7 was the Thiel flagship for good reason. They offer extreme clarity, speed, coherence and grace, and refinement that is among the very best available. That said, system and room matching are absolutely critical to get the most from them. If you get it right, the rewards are well worth the effort and cost IMO. From years of Thiel experience (2 2s, 3.6es, and now 3.7), there are some guidelines that may help.
I never wanted to do it, but tube anything tends to relax Thiels. My best advice is to include a high-quality tube preamp/linestage. As important is to choose an amp that can pass large amounts of current. If the amp can double its power when the impedance falls by half, you are going in the right direction. Finally, you need to be at least 8 feet away from the speakers to have them sound their best. That plus maybe 3-4 feet of clearance behind the speakers and another 3-4 feet behind your listening position. You should also have room to keep them 3 feet or more away from sidewalls. Tubes matter with Thiels, high current amplication matters, and your room definitely matters, a lot. Here are some additional thoughts that I have found useful-
https://forum.audiogon.com/discussions/thiel-3-7
and from Stereophile-
"Editor's Note: Class A "Loudspeakers" are sufficiently idiosyncratic and differ enough from one another that prospective customers should read Stereophile's original reviews in their entirety for descriptions of the sounds."
Perhaps a listener should trust their ears in their own particular situation rather than taking as gospel what reviewers publish. However, reading reviews can offer good guidance on how one might get the best from such beautifully conceived and executed "Class A" instruments. The Thiel 3.7 is certainly, within its limits, a beautiful loudspeaker. It should, given the right set-up and support gear, easily surpass the performance of the 2.4 IMO.
Hegel Mohican CD
Audio Research Reference 3 Linestage
McCormack/SMc Audio modified DNA 1 Amp
Shunyata Alpha HC power
Kimber Monocle XL speaker
Audioquest Columbia XLR interconnects
Audioquest Niagra 1000 power conditioner
I never wanted to do it, but tube anything tends to relax Thiels. My best advice is to include a high-quality tube preamp/linestage. As important is to choose an amp that can pass large amounts of current. If the amp can double its power when the impedance falls by half, you are going in the right direction. Finally, you need to be at least 8 feet away from the speakers to have them sound their best. That plus maybe 3-4 feet of clearance behind the speakers and another 3-4 feet behind your listening position. You should also have room to keep them 3 feet or more away from sidewalls. Tubes matter with Thiels, high current amplication matters, and your room definitely matters, a lot. Here are some additional thoughts that I have found useful-
https://forum.audiogon.com/discussions/thiel-3-7
and from Stereophile-
"Editor's Note: Class A "Loudspeakers" are sufficiently idiosyncratic and differ enough from one another that prospective customers should read Stereophile's original reviews in their entirety for descriptions of the sounds."
Perhaps a listener should trust their ears in their own particular situation rather than taking as gospel what reviewers publish. However, reading reviews can offer good guidance on how one might get the best from such beautifully conceived and executed "Class A" instruments. The Thiel 3.7 is certainly, within its limits, a beautiful loudspeaker. It should, given the right set-up and support gear, easily surpass the performance of the 2.4 IMO.
Hegel Mohican CD
Audio Research Reference 3 Linestage
McCormack/SMc Audio modified DNA 1 Amp
Shunyata Alpha HC power
Kimber Monocle XL speaker
Audioquest Columbia XLR interconnects
Audioquest Niagra 1000 power conditioner