There are a number of other issues that I think are behind this discouraging lack of performance from allegedly high-end audio companies, besides the well known "placebo effects."
Speakers aside, the audible differences between reasonably well-designed pieces of gear a negligible. (Ignoring gear that deliberately distorts).
So why do people get so hung up on these things?
I conjecture the main reason is that they feel dissatisfied with the sound they are getting from their current system. This is where the speaker quality issue can really throw people off. Instead of looking at the speakers, placement, and room treatment, the dissatisfied listener reads about some new device that "opens up the soundstage" or whatever, and is convinced to buy.
Another reason is that the quality of the audio production, including the musical elements, vastly outweigh every aspect of reproduction system quality. (It's amazing how a really well-produced recording can sound great on a mediocre playback system, as an example from rock music, I'm consistently impressed with the production on Radiohead's records, after The Bends, these guys and their producer are at a whole other level...)
There is quite a range of quality in production, and it's a mind-bogglingly complex thing to get "right"...especially as this includes innumerable subjective factors. Every audio production you hear, except maybe purists stereo recordings, has gone through both analog and digital processing that introduces far more "distortion" than anything found in a competent playback system.
Another issue is that the critical listening skills required to evaluate any aspect of music (re)production are not trivial. Especially the ability to diagnose the cause of unhappy feelings when listening to recordings on your system.
One of the biggest problems in critical listening is that our perceptual system has "circuitry" that "fixes" problems in audio, the best it can, in real-time. There is simple test to illustrate how strong this effect is: find a playback system. It could be in the car, computer, it doesn't matter. It just needs to have reasonably easy to operate tone controls. Listen to 30secs of a song or so, then crank the bass all the up for 30secs, when you turn the bass back to flat the music will sound "tinny" lacking in bass. You will get the opposite effect with the treble control.
These perceptual effects combine with aspects of conscious attention to different parts of the musical sounds, of which there are often hundreds or thousands in a complex production.
Now consider again the multitude of sources of expectation bias, visual bias, emotional and physiological states that affect perception!
The result is that things never "sound the same." Each playback will sound different. The beginning of a single playblack will sound different from the end.
Combine this with the fact that we all only listen to a tiny subset of all possible recordings, usually of which we know little about the production itself, and it becomes very hard to decide whether something "sounds good"!
This can lead to "chasing your tail", switching in and out different parts of your system, one time thinking this amp sounds so much better, another time being convinced that the converters in your old CD player sound much different than these new-fangled DACs!!!
For myself, the advantage of having a piece of gear that measures up to a standard level of performance is that at least I can "rule it out" as being the source of frustration with my music listening experience.
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March's point about it not necessarily costing more to manufacture good performing audio gear is well put.
While I think getting the best audio performance "just for the sake of it" is an interesting project in-and-of-itself, it's interesting how it can also lead to the exact same phenomena that peddlers of "snake oil" products rely upon! Expectation bias.
What I would like to see from audio companies is focus on hitting a specified level of performance that is "good enough" in that gains beyond are not audible. Then the buyer could "rest easy" in this aspect of purchasing. There remains plenty of room for improvement in many other aspects of equipment design:
- cost, manufacturing cost, green production techniques
- proper safety design and testing
- reliability/repairability
- upgradability, mod-ability
- features, it's surprising how hard it still is to find gear at the price you want that has the right combination of features!
(I want an affordable DAC/amp that would run custom dsp EQ curves. Look at the massive amount of functionality found in the average AVR, for the price. Basically, a product that strips that down to a USB input, spdif input, and maybe two rca inputs would do the trick. There's already extensive dsp capabilities in these AVRs, there should be more than enough horsepower to run 6 channels of parametric EQ or so. But there is no good way to access it in current AVRs, Leave out all the extra stuff, making it smaller and cooler.)
- ergonomic issues...the functioning of the controls on an AV playback system is a huge factor in subjective performance. Just having tone controls vs having to go into submenus with the remote makes a concrete difference. Likewise with the resolution of the volume control. The amount of gain, and the taper of the control, can have a big affect on how I "feel" about a system.
- power consumption/heat relative to performance
- size, physical design, weight