Which area of components to spend the most $ on? Boy I was wrong all my life!

My experience that the Room is the most important "component". The second most important "component" is matching the speaker to the Room. I have heard systems at shows that cost hundreds of thousands of dollars yet sound worse than a Sonos. I have heard mid priced systems that make me smile when played in a room that has been set up correctly. If you check the major magazines and dealers (what is left of them) you find a plethora of great manufacturers. So Room, then matching, then fill in the rest.

My feeling is that AMPLIFIERS are the weakest part of the whole chain.  They always have been, in my audio experience going back 50+ years. 

The amps are FAR worse than the speakers.  

In 2019, I find that 99% of the amps one can buy, don't cut the mustard.  Also, VERY few people, active in audio, have long-term heard these amps in the 1% bracket.

The best sounding amps, IME, will be 2 Watts or less, tube, with absolutely NO negative feedback loop.  Only from this amplifier topology have I heard playback that is long-term satisfactory to me.

You pick the amplifier first, ................and the rest of the system follows suit.

The speaker will be a two-way, highly efficient / sensitive, in the 99 to 101 dB or higher range, and the woofer will be a 15 inch.  The speaker's enclosure will be ten cubic feet as the minimum size, no open baffles.  ALE, GPA, or some vintage ALTEC drivers can be used, with care, slight mods.

To obtain maximum dynamic contrasting, and wide band response,  the audio wire will have silver content, and I like to see multiple paralleled wires, the total equaling about 8 AWG , per polarity, for this 2 Watt amp.   Use of 8 AWG equivalent wire STARTS inside the amp, with the Power Transformer's High Voltage winding's center tap, and it extends, amp-to-crossover, through the crossover, and all the way to the voice coil terminals of fifteen inch driver.

The "ultimate" useful amplifier topology will " only and always " be simple - as follows : Two Stages, Direct Coupled, either SE or in Push Pull, using triodes.  This topology is hard to find, done really well, so I DIY design and build my own. Its a lot of fun.  Good luck in your quest.

Front end ( source ) equipment in 2019, is NOT the weak link.   We have some very good sources these days, if selected intelligently.  Amps that are truly superb, as always, still in my opinion, remains as the problem.

Dowto1000

I invest some of my money every 6 months to get my ears professionally cleaned. Best trick I have ever found. A good Ear, Nose & Throat Doctor will use a vacuum device and not the old bulb and warm water routine. You can put this on your insurance also. So here is a low cost fix that is a great help.

I have been buying high end speakers for the past 20 plus years.  I find speakers make the biggest difference in overall sound than any other components.  I usually keep speakers about 6 month and then move on to something new.  It is fun to try different things. 

I also like to try speakers that look good as well.  MBL's come to mind.  Currently I have Stealth 6's and they are great looking speakers.  Everybody who comes into the sound room has something to say about them.  They do steal the show!

"The front end sets the limits of resolution for the system."  As many have said in this good thread.

How does that signal get to the rest of the system?  Wires.  No matter how good the source component is and how great the signal it produces, if the wires won't let most of that signal through, very little has been gained by the otherwise correct focus on front end.

Learning the effect of wires a few years ago was the biggest, most unexpected--and most cost effective--piece of learning in my decades of building a system, and one that has been repeated many times as I've gone through a total upgrading of my system's wires.
Jim Heckman