The red line is the built-in laptop speakers I had been using. The green line is the Bose I listen to now. Seems like decent highs and lows to my eye. 1/3 octave smoothing.
Nice that you use REW despite limited gear (thus far)!
Obviously, built-in laptop speakers have some severe space constraints and are a "low bar" for sound quality comparison.
At first glance, your Bose plot looks surprisingly good; however the main reason it looks good is because the y scale is extremely compressed! Having a minimum value of
negative 50 dB doesn't make sense as SPL can never be less than zero! It looks like your plot is centered at SPL=60, so I would set the bottom limit to about 40dB since 20dB down is out of the picture any way (20dB is a huge change in perceived level).
If your speakers followed the green line up to where they cross around 1500Hz, then switched to the red line, that would be a decent response for a portable BT speaker!
As is, your Bose has great performance from 70 to 700Hz (although some serious smoothing is being applied, but we'll just read the plot as is)! Then we see a 7dB increase as we go to 1300Hz followed by an abysmal 17dB drop by the time you get to 4.5kHz. As a general rule of thumb, anything down by over 10dB is going to be "absent" from a SQ perspective when listening to music.
So across the "high midrange" (2-6kHz), which is one of the areas our ears are most astute, you have a dramatic drop-off (I should probably call it a drop-out, because it is really gone at -17dB).
Looking at recording engineer guidelines:
~4kHz is the domain of percussive attacks
4-6kHz is where clarity and definition are conveyed, and
6-20kHz are where "brightness/crispness" are conveyed.
So, I would expect you are very happy with the fullness/warmth of the sound of your Bose, which is really pretty decent below 1500Hz, given its size. However, the Bose will sound a bit dull, and, as you listen to quality speakers, you will be thoroughly impressed with the detail and crispness they bring to the table. The unique thing about the Bose is they appear to have chosen to focus on the lower end, which is the most difficult aspect of a small speaker, at the expense of the upper end, which should be easy - as you laptop shows (though your laptop may have lots of distortion at those frequencies, which would not show on the FR plot).
If I can assume as your criteria $1000 max for a pair of speakers and no cost to trial (free return shipping), I would suggest you trial the SVS Ultra Bookshelf speakers. I have heard plenty of speakers and feel these are very good for their price point. They will have enough bass (obviously tons more than you have now) for most music. Then you can add a subwoofer later if you so decide.
https://www.svsound.com/collections/ultra-series/products/ultra-bookshelf
I also think the RSL 2.1 system previously mentioned represents a good option.
https://rslspeakers.com/products/cg23-2-1-stereo-speaker-system/
Note that you can save $200 by getting the cg3 2.1 system instead of the cg23 2.1 system. If you are listening close to your speakers (like a desktop setup), I would recommend the cg3, but if you want to use them in you living room and have some decent volume, the cg23 are what you should get.
Ideally, you can float both the SVS and RSL speakers on your credit card and have them in your house at the same time to compare. Keep the one you like better (or return both if you don't like either - I think you'll love both), both of these companies will refund your money and pay return shipping without any hassle - they understand that is necessary if they are going to succeed (and both have been around for well over a decade).
Last, I would suggest you consider buying a refurbished AVR from Acessories4Less. As a rule, you can buy a lot more receiver for the same money (or get the same AVR for a lot less); however, always check pricing at Amazon, because there are ocassionally deals on discontinued AVR's where it may cost just a bit more for a nib discontinued AVR, for example! I have bought several AVR's from them and all have worked perfectly.
https://www.accessories4less.com/make-a-store/category/avreceiver/home-audio/receivers-amps/home-theater-receivers/1.html?store_price[]=101-2400&brand_f[]=DENON
Best wishes
PS - If/when you call RSL or SVS, talk to them, they offer excellent customer service and you might as well get some of that goody. Be honest, if you are doing the comparison I suggest above, I say let them know up front. Trust me, you are not the first to buy speakers knowing there is a 50% chance of return (often less, if a 3 or 4 way comparison is being made).
