I have read some people's experience indicating that one needs to measure an amp while connected to an actual speaker, to get the real-world response. A speaker is a non-ideal load with varying impedance, whereas in test conditions, a simple well-understood resistive load is used. I'm not enough of an expert to understand how much this matters, but it is a point of difference in the test vs. use-case.
Yes I agree to your points and a lot of the other points here. I am very likely at a saturation point in my system, at least without going to a much higher-level budget.
Now that I think about this more, the points I am really thinking about are (and sorry if I'm rambling a bit):
- Why is there not a "preference rating" for amplifiers, like there is for speakers (one can argue on the validity of it, but it's based on real research/studies and is something that's trying to quantify the subjective nature of audio and does a reasonable job at it)? This would help the consumer decide better on what to buy and how much to spend. Or is it that most amps would just score 10/10, and this would be pointless?
- Does a $100 amp sound any different than a $1k amp? I, as a consumer, would like to know, so I can make an informed choice. Yes the electrical parameters are certainly better on the $1k amp, but can I hear it? What does the microphone say? Also note that measuring audio with measurement mics is very accessible to most people ($100), vs. a signal analyzer that runs many $ks and requires quite a bit of knowledge to use. Thus, using metrics based on sound can be done by many people... and if an amp does sounds different/better, it
should be measurable by a microphone and the difference can be explained quantitively.
- How much power does one
really need? I hear a lot of people wanting extra headroom/capability, but will it ever really be exercised? I was listening to music last night and used my phone to measure the SPL - it was barely 70 dB, and I felt it was getting too loud (I presume the phone is doing some time averaging though, and the peaks were higher). That should imply my speakers are drawing <1 W on average. Why in the world would I ever need >200 W that some amps advertise? I doubt any transients would ever require that much power draw at listening levels I feel are sane (which are also "safe" in terms of ear health and aging - this should be seriously considered by individuals).
- One analogous example I want to point to are speaker cables. It seems to be the general consensus on this forum that all you need is some plain ~12 AWG zip cord cable (preferably OFC?) and you're set; anything else is a waste of money. Well, if I look at a cable like Kimber 8TC (
measured on audioholics), the electrical measurements point to it being a better cable than regular zip cord. But alas, it's doubtful one would hear any difference (even Gene on Audioholics says alludes to this in his video, and he does it for the "jewelry" aspect). So, why is there a disconnect in the thinking of amps, vs. cables?
For my own knowledge, I will plan on assessing various amps subjectively and objectively (based on audio sweeps and detailed time/frequency domain analyses that REW offers). I have my x3600 receiver as a baseline, various cheap class D amps ($30 to $100 models), and will look into trying out more expensive amps (perhaps the Topping PA5, and then a Hypex or Purifi amp). I think the average consumer should know whether a cheap $30-$100 amp is essentially the same as a >$1k amp in terms of perceived audio quality; or perhaps not, and how much difference there is if not - so an informed decision can be made on whether to spend money on something expensive. Of course my personal experiments with the limited hardware I have is not going to answer this universally, but it will answer it good enough for myself (and hopefully it will be useful information for others).