Best monitor for under $4000.00

I have a dedicated listening room that is 13.5 X 18 X 8 high and is a well treated listening environment.I use Thor TA-1000 preamp with Thor TPA-30 mono blocks.They are 30 watt el-34 tube amps with understated power!I have had Kharma 2.2 before and though they sounded nice the room was overwhelmed with them!

I listen mostly to vocals,small jazz groups amd aucoustic music!I listen at low to moderate levels.I know I need to demo...but please point me in right direction.Speakers I am interested in are

Refrence 3a de capo
Harbeth 7es
JMR super bliss
B&w pmi
spendor models
merlin tsms
I have the De Capos so I'm biased :) but i have used them with 3 different tube amps and they sounded great with all of them. 35 wpc PL2, 4 watt decware and 10 wpc Vista Audio I84.

they come up used btw 1000 and 1500 and sometimes higher.
I will go with Harbeth 1st Capo 2nd but Harbeth is $700 more expensive.

If I were you with $4000 , I will get Tannoy Stirling SE
How about KEF LS-50 with a REL sub, for low to moderate listening you may not find a better monitor. It will certainly compete with monitors you mentioned. At the very least give it a listen, it is unlike anything I have heard in years.
I recently had my Merlin TSM upgraded to the MMM version by the manufacturer. I have owned many stand mounts and these are in a class of their own with this upgrade.You owe it to yourself to check them out.Bobby at Merlin will answer any questions you have,customer service is the best.
Throw in ProAc D2's for good measure....
All good choices; a lot will come down to taste and synergy with your room and equipment (duh!) :-)

I have owned the Merlins and they are very fine. I currently have the De Capo's and love 'em to pieces.

Have fun!
Since you are using a tube amp (with probably a high output impedance), you need to use the impedance graph of the speaker to guide your choices. And I'm not talking about how difficult of a load the speaker is. I'm talking about the lack of variation of the impedance. You want more of a constant load.

Here's two examples:

Too much variation, Spendor SA1: The peak in the midrange is going to make that region sound forward.

Near perfect, Thiel PCS:
Check out the vapor audio cirrus. I don't think you will get better in the neighborhood of $4k
Whatever you do, if buying new, go with a long standing reputible company that has a warranty and accepts credit card payment. I learned the hard way!
Some excellent suggestions here. I just bought a pair of Fritz speakers, the Carbon 7's, for number 1 son. Sold direct by the manufacturer, so cuts out the cost of a retailer and very high quality drivers and cabinet construction, also available for 30 day home trial I believe. Fritz himself could'nt be more helpful. What's not to like.

So if you want to get a good bang for your buck, take a look at the Fritz Speaker website, check out some of the reviews.
I would add Canton Reference 9.2 DC to your audition list.
I can only say that I love my TSMs. And that I have owned B&Ws in the past and founding them wanting. Things may have changed since then, however. Unfortunately, I have not heard the others.
The BEST is the Bryston Mini T. Please audiotion a pair before you buy and you will be convinced. I have both the Mini T and the LS 50. I use the LS in my Studio but have the Mini T for 2 CH listening. You do NOT need a sub for the Mini Ts :) I purchased them at engulfaudio
You can get Selah Audio Tempestas in basic cabinets for ~$3300. Some of the world's best drivers, artfully combined. Best I've heard. They are his top selling model, yet none have ever been re-sold, to my knowledge. That says a lot.
Paradigm Signature S2

I thought they were very revealing with their Be tweet.
with the right platforms and footers, they are really nice for acoustic and live type music.

And the build quality is excellent.
Fritz carbon 7, rev7, and Illuminator 7 be are all very good and incredible value for the asking prices. I heard them all in my room, and my favorite was Illuminator. But all are very very good. Very nice open and refined sound
Given your music preferences, beyond the choices listed above, you should consider: Dynaudio C1. Perfect for your music and room size. Now that the model has been and updated, you should be able to find some C1's around here for at (or perhaps slight above) your budget; but it woud be well worth it.
A third vote for Fritz. I own Carbon 7's and plan on upgrading to Illuminator 7's in the near future. You won't find a better value in the $2000 - $3500 range. The ScanSpeaker drivers that he uses in the Illuminator 7 are found in brand name speakers that cost upwards of $20,000. Also: no need for a subwoofer. I like impactful, noticeable bass, but the bass from the Carbon 7's is simply unbelievable. It defies their small footprint. I own two sealed Hsu Research subwoofers but I keep them off simply because the bass from the Carbon 7's is just right for my 11 x 15 room. I'd imagine it would be sufficient for bigger rooms, too, although I can't say from experience.

Here's a link where someone (username Koven) did a shootout between similarly priced models from Totem, Fritz, Joseph Audio, Usher, and Harbeth. Ultimately he chose the Carbon 7s. Fritz will let you do an in-home demo to see if you like his stuff. If you can't do a demo, try to swing by an audio show and hear his stuff. It seems like every show he goes to, his room is always considered one of the best.

Note: I have no affiliation or obligation to help spread the word about Fritz's products. They're just that good! Also, it doesn't hurt that he's such a genuinely nice guy. I've had many hour long conversations with him about my audio setup.