Opinions wanted: 10-30K Speakers for Jazz/Folk

Agreed.  Their are many products in this price rang that meet the "sounds great for jazz and folk" but there are so may styles and different types, it is tough to suggest anything. 

What are the room dimensions?  How far will you be sitting from the speakers.  What kind of flexibility will you have in terms of placement?  Within 2' of the wall.  2' to 4' from the wall.  4'+ from the wall.  This has a MASSIVE impact on what works?  Limitations in terms of design?  Floorstanding or Standmount?  Would you add a subwoofer or two?  What about acoustic treatments?  Are they an option?  

For listening experience, do you like the sound presented to you or do you want to immersed in the experience?  Do you like a more forward or laid back sound?  Any preferences in terms of energy usage?  Tubes okay or are they a no go?  

Here are four very different speakers that would be in your range - 

Avantgarde Zeros and Unos which are amazing speakers and can be driven by flea watt amps.  They are great in medium sized rooms where setup is a pretty optimal equilateral triangle.  Insanely good with an Art Audio PX25 but they look different and are you open to low powered amps?  How is your room?  

Wilson Benesch has 5 models in this range that work with normal placement but which model depends on a lot.  They work in a pretty typical room but require a minimum 100w of power and are a relatively neutral.  Could drive them with Chord or AVM and net result would be forward chord, neutral with AVM.

There is MBL which is omnidirectional and delivers a massive soundstage.  Best with their own electronics and they have three models in this range.  Wild speakers but need to know about your layout as they require certain spacing to be at their best.  . 

Vivid three or four models in this range.  They are a bit more forward but the designs are extremely unusual and work well with near wall placments.  They need warmer amplification like Naim or AVM.  

Focal has multiple products in the range as does Magico, Wilson, Kaiser, Raidho, B&W, Harbeth, YG, Stereokonzept, Sonus Faber, Rockport and many, many more.  Without narrowing, you will get so many things to research, it will be overwhelming with no good way to narrow it.  

Marten speakers are great!  I have a friend who just moved from Kef Reference 5s to Marten Mingus Quartets. He is driving them with AVM Ovation MA 8.3 Mono-Blocks and it is insanely good using his Chord Dave as DAC and Preamp.    

I believe for floor standers, you are going to want to look at the Parker or Mingus lines from Marten which if you can't find them used, might be above your budget.  Great speakers and are best with lots of power and warmer amps.  

Which Audionote, UK or Japan?  I am familiar with the products.  I import and sell a competing line called Art Audio which, in the right application, are insanely good.  They tend to be lower power, tube amps.  

I know Spectral makes great gear.  I am not a huge fan of that 70s mainframe computer look personally but it is VERY good equipment.  

These amp recommendations are all assuming normal, neutralish sources.  You can always change up amplification if you use a particularly bright (Mola Mola DAC) or warm source (Lampizartor DAC).

So, here is what I think is a must consider.  Might cross it off after a second, but it's worth a look.  

Avantgarde Zeros and Unos.  They have fully powered units and ones that require separate amps.  Generally, a good low powered SET like an Art Audio PX-25 or Diavolo are best with these.  They have powered bass units so are VERY full range.  Take some effort to get setup and dialed in but when done, nothing sounds quite like Avantgarde.  

Vivid Kaya 45s and 90s New, Giyas used.  These are obscure looking speakers and are true form follows function designs.  Fiberglass cabinets with drivers that are created to properly interact with the cabinet.  The designs are no weird for the sake of being weird, they are their tom minimize standing wavs.  Technologically, designed to optimize sound.  They like a little bit of warmer power as the speakers are a bit forward naturally.  I would recommend AVM amplification to go with them and think the result would be brilliant.  I just spend time listening to a piano concerto on these and it was....memorable.  I personally am about to order a pair of Kaya 45s as demos.  

Wilson Benesch Vector is a brilliant speaker.  As you rise in WBs geometry series you get some really cool technology but even these base models are technologically incredible.  Carbon fiber cabinets and customer drivers.  This is a more neutral/natural sounding speaker and doesn't require warm amps to be at their best but will deliver beautiful sound with a warmer amp but will be decidedly laid back.  Good with AVM if you like a more laid back sound, Chord Ultima for a more forward sound.  

MBL Hybrid speakers.  I would look at 116s and they are definitely best with MBL amplification.  MBL are going to deliver a massive, immersive listening experience that is incredible.  You won't feel like you are in a small jazz hall, you will feel like you are on stage with the band.  It is incredible but not for everyone.  MBLs amps are shockingly powerful and yes, you need it.  

Magicos S3MKII or S5MKII.  These are aluminum cabinet speakers with a BE tweeter.  They look normal, but are very well designed and deliver precision.  The listening soundstage is presented to you and they do like a lot of power.  I would suggest AVM amplification.  

Martin Logan 15a electrostats.  These have powered base units as well and are going to deliver a huge and immersive soundstage.  Similar yet different approach compared to MBL.  They are power hungry and a bit bright.  Warm amplification is required so I would look at AVM.  

Focal Sopra with Naim amplification.  Focal is a unique looking speaker and they are super engaging.  Focal and Naim are owned by the same company and go together like Peanut Butter and Jelly.  Similar in presentation to Magico, they are delightful.  

B&W 800 series.  This is a must review speaker simply because.  To me, the deliver an incredible, detailed, image but I find the overall soundstage is less defined.  It sound different than many on here.  Goes well with McIntosh amplification and any other warmer amplification like AVM.  

Vandersteen.  I am not an expert on this line but it is legendary.  I think the Quattros would be in the right price range.  Best with Ayre amplification.  

Harbeth is a line like no other.  Where many brands try to dampen resonance, they embrace it and harness it in a positive way.  This brand has an intense and loyal following.  You either love it or nothing it.  I don't know if I have ever met someone who hates it.  Just too well made to dislike them.  They like power and you can drive them with something a bit brighter.  

Wilson Audio Sabrina X and I am sure one other model is in this range.  They use a cast resin cabinet and very traditional drivers to deliver  a huge sound.  They work with lots of different amplification but most prefer something neutral to warm like AVM or Luxman.  

There are others that are redundant to many of these.  If you love Harbeth, then you should also look at Spendor or Stenheim.  If you like Margico, check out YG and Stereokonzept, etc...

This to me is a good place to start your research.  I sell a lot of these, not all of them.  I will answer any question I can.