Is my Amp OK?

No speaker is ever better than a decent amplifier. Frequency response of even the best speakers is at best within +/- 2dB for the central part of the spectrum. Good amplifiers stay within 0.2 dB, or even far less. Distortion figures are a similar story.
The explanation is very simple: speakers have mass that can resonate, is slow, behaves in a non linear way etc. Good amplifiers have been sonically perfect for decades, and cannot be distinguished from each other in a double blind test.
See here for the classic and legendary test: http://www.keith-snook.info/wireless-world-magazine/Wireless-World-1978/Valves%20versus%20Transistor...
And here for a hilarious one: http://matrixhifi.com/ENG_contenedor_ppec.htm
If you google you will find quite a few more.
I personally attended a private demonstration by Quad's designer Peter Walker. He had this set up where you could listen blind to his three famous amplifier designs (using studio master tapes). I thought I could hear a difference, but he just grinned: I had been no better than random. That was a lesson learned.
There are a few proviso's and I have listed those in my earlier post. If those apply, there will be sonic differences because one of the amplifiers does not meet the criterium of 'properly designed and used within its specification'. This is why many tube amplifiers fail the test.
If that is not the case, the perceived sonic differences are the product of level differences (the brain interprets louder as better). For a listening test levels should be kept within 0.2 dB, and that is such a small difference that you can only achieve this with a decent Volt meter (and not with an SPL meter, let alone with a smartphone app). Did you ever see a dealer equalizing levels in the demo room using a Volt meter?

Sonic differences between well designed amplifiers are minimal at most.

 No speaker is ever better than a decent amplifier. 

I have to disagree with these statements.  Anytime you want to swing by and hear some custom built amps and speakers let me know.

Happy Listening.

willemj

Good amplifiers have been sonically perfect for decades, and cannot be distinguished from each other in a double blind test.

Julian Hirsch proclaimed that too, at Stereo Review back in the ’70s. He was so wrong then that he helped give birth to virtually the entire high-end audio industry. Some people credit publishers such as Harry Pearson and J. Gordon Holt with helping to establish high end audio, which is valid. But without Hirsch’s "it all sounds the same" dogma, it would never have happened the way it did.

As Hirsch was wrong then, so are you mistaken now.

Well, I am a scientist and I cannot accept uncontrolled sighted experiments. There are rules to distinguish fantasy from fact, and in my book alternative facts are just fantasies. So why do people put more faith in their owned flawed experiences than in properly controlled experiments?
As for my own listening experiments, I can refer you to my participaption in Peter Walker's test. For me, that and the many similar experiments that you can read have clinched the argument. I am not an audio hypochondriac.
For years since the 1970's my own gear has consisted of Quad ELS 57 speakers driven by the Quad 33/303 amplifier (periodically refurbished). Some years ago I replaced the ELS57's with the (less efficient) Quad 2805's. Since we had also moved to a larger house with a far larger listening room, the 2x45 watts of the 303 were no longer enough, so I replaced it with a refurbished 2x140 watt Quad 606-2. Interestingly, and predictably, there was no audible difference at lower volumes, but the sound was/is now cleaner at higher volumes - I had been driving the 303 outside its comfort zone. More recently I added a B&W PV1d subwoofer, with Antimode 8033 room equalization. In short, the speaker system is revealing enough to show up any weaknesses earlier in the chain.
My desktop system used to have LS3/5a speakers driven by a variety of smallish amplifiers. Some time ago I replaced the LS3/5as with the far better Harbeth P3ESR mini monitors, and I acquired a completely refurbished 2x100 watt Quad 405-2 power amplifier to drive them (having learned the importance of power). Sufficient power is indeed important, and as I wrote earlier, does make a sonic difference, so I am pondering 2x260 watt Quad QMP monoblocks.
Very recently I bought my son a 2x250 watt Yamaha P2500S for his birthday (he is saving for a pair of Harbeth M30.1s, and currently uses my LS3/5as). Again, as was to be expected, the sound is absolutely fine, and indistinguishable from the Quad 303 that he had borrowed from me before. And for now the power limits of the LS3/5a do not allow him to experience what big power does.
So all in all, a lot of happy listening is going on.