You should always chose your speakers first, and then select components which work well with the speakers you have selected. All speakers have flaws which you must choose between so speaker preference will be extremely personal. This is often demonstrated by people who agree about the relative merits of a amplifiers or DAC but disagree about speakers. It’s also useful to identify what speakers you will be using because speakers vary in what they require from an amplifier depending on their efficiency and impedance.
The cheapest way to get truly excellent speakers is to purchase great headphones. Often you can build headphone based systems which will be one fifth the cost of a similar quality speaker based system.
Electrostatic & Planners
I have found that the speakers that I generally favor electrostatic speakers made by Martin-Logan, SoundLab, Audiostatic, and older Quad. I also to like panel speakers that use ribbons such as the original Apogee and the reborn Apogee Accoustics. While I don’t like Magnepan speakers as much as pure electrostatic speakers, I think they deliver an excellent value, providing sound quality that rivals speakers nearly twice their cost with the MG1.7 providing the their best price/performance.
Planner speakers are particularly well suited to the sort of music I like: “small” and intimate. Vocalists, chamber music, folk, blues, and small jazz combos. I want clear and tight bass, but it doesn’t need to shake my bones. I want something that gives me a lot of detail, and has exceptionally smooth vocals. Most panel speakers, once properly place give superior soundstage, and are particularly good in the mid-range and higher frequencies. Weakness of most panel speakers is that the absolute dynamic range is less than a conventional design, they tend to be large and touchy about placement, and may have a weaker bass end. Sometimes panel speakers will be paired with a dynamic woofer, since the real-estate required for a good panel woofer is quite large such as in the Martin-Logan Aerius which I used for many years.
Horns were theoretically a very cost effective way to get audiophile level sound quality, but it was very challenging to get the built and set up right. With modern 3D printing and software modeling it’s much easier to do effective horns. I am sure a bit of searching on the web would produce a mound of useful information.
For people on a tight budget I generally recommend the NHT super line. I would also recommend the Wharfedale Diamond 225 and KEF Q350. Other lower priced speaker which have gotten good reviews include the Elac Debut B6, Aperion 422-LR, Axiom Audio Millennia M3Ti SE.
There were a lot of well regarded speakers $2000-4000 range which didn’t impress me. Yet, there are a lot of people who seem to like them. If you don’t like panel speakers, I would suggest checking out the somewhat bright Thiel, warm Vandersteen, or the fairly neutral speakers from KEF or B&W. I would also recommend checking out GoldenEar speakers even though I haven’t listened to them because people I trust rate them very highly. My favorite dynamic speaker made by Aerial (particularly the Model 10T, now 20T) and Sonus Faber (Electa Amator and up).
In 2017 I moved to a new home and my Martin-Logan Aerius just didn’t fit in. After a bit of searching we found that the KEF LS50 wireless monitor speakers were the only speakers under $10k was there visually acceptable to my wife, and sonically acceptable to me. The LS50 wireless are a mini monitor with a built in DAC and amplifier designed for the speakers. Good quality sound that fills a room, and excellent sound quality for near field use. Can take TOSlink, USB, Bluetooth, analog, and several IP based streaming protocols inputs over ethernet or WiFi. Roon can stream directly to it over the network, but it’s not Roon-Ready so can’t be synchronized with other Roon-Ready systems. The iOS remote application is poor. I drive the LS50W via USB on a computer running Roon which remove the need for the KEF remote and the speakers can be synchronized with other Roon Ready end-points giving me whole house music. I still prefer the sound quality of electrostatic speakers driven by separate audiophile grade electronics, but I am happy that I downsized my audio system so I could focus on other things. KEF has released the LSX which is around 1/2 the price of the LS50W which are smaller and have a lower sound quality.
Less expensive is the Roon-Ready Pulse Flex 2i which allows me to have synchronized whole house music. It also supports inputs via USB, Bluetooth, AUX, Airplay2, and a number of streaming services like Spotify and Tidal. Has a decent iOS and Android remote control app. Controls on the top let you select one of 5 user-defined “channels” without using the remote. I have the optional battery pack so it can be used in our backyard. It can be used away from it’s home, but you have to reconfigure it’s WiFi settlings which is a pain. Sound quality is significantly less than KEF LS50 but cheaper and much more portable. For people who aren’t using Roon, I would recommend Sonos: for it’s lower price point, better streaming options, and slightly more processed sound quality which everyone but audio purists like me typically prefer. If you are really trying to keep the price down consider products from Audio Pro, or use one of the small smart speakers from Amazon or Google.
I have yet to use a smart speaker that I thought had reasonable sound quality. The Apple speaker is the best sounding I have heard, but is a far distance from “audiophile” speakers, and the voice recognition is still a distant third to Google and Amazon.