Transients hurting my ears on hifi solid state amps

Thanks @holmz for the various very good points and suggestions. Just a clarification on one point, as this is one of the things I'm trying to understand here:

I doubt that the amps are any “faster”, as most amps play 20kHz just fine, and nothing is going to arrive faster from a 2kHz signal, than a 20kHz signal.

With fast I mean that the transients, the typical example being the hit on a snare, are quick and powerful. So in a graph measuring the sound pressure, the peak would be higher and narrower on a "fast" amplifier and lower and flatter on a "slow" amp. The sound is more compressed in a "slow" amplifier and thus the hit of a snare or the initial transient of a piano note will be felt as softer by the ear.

I understand that there are other factors discussed that heavily influence the perception, but I do believe that this is part of the equation. Low powered amplifiers would in my understanding be therefore more suitable to avoid the problems I've had. It is not so much sustained notes that cause issues for me, but the percussive sounds and initial attacks on many instruments.

Pre-owned Parasound A21 amps can be found for ~$1200. Their distortion profile is primarily 2nd order, which is very rare among amps below $5K, and output enough power to provide plenty of headroom for nearly any speaker.

Your argument is exactly the opposite of what I'm discussing in my previous post and I find that really interesting. I would need to experience that for myself and see whether the distortion profile would be enough of a key factor. I definitely get the idea of more clarity making it easier to hear details and thus make listening less fatiguing. I wonder whether this is what I'm sensitive to. The combo you propose does sound very attractive and reasonably priced.

 I misquoted the power on the Pass though.  It’s 25 Wpc at 8 Ohms, 50 Wpc at 4.

Thanks for the clarification @wlutke, 50 did sound a lot from what I remember about those Pass amps. My speakers are not the most efficient either, so not sure it would be a great match, except if my low power hypothesis is correct. I don't mind if the sound is smoothed out a little, like on my tube amp in triode mode.

I am experiencing a like problem. In my case the "listener fatigue" symptom came on like flipping a switch. No changes to my rig.

Fingers are crossed I have had a E/N/T infection that became worse, so it is to the Audiologist for me as soon as I am convinced I am feeling better.

How am I sure of this? After my system started sounding like poop I have tried everything to solve it through DSP/EQ via Roon. Days of going through all the possible offending frequencies, speaker placement... even the old Yamaha NS10 trick.... gauze over the tweeters lol! 

I will give David Hafler (RIP) his props. I purchased a DH220 in 1981, another in 1985 which is in use now. Both amps sounded great! I had the 1985 upgraded in 1989 by Musical Concepts. Sounded better all the way around.

A little over a year ago it was upgraded again with all Fantasia Audio boards, caps. All jacks and speaker terminals replaced with Cardas. Morrow Level 3 power cable hardwired. Total investment since 1985.... $1500.00, $41.00 a YEAR! Oh, and in my configuration of nearfield, 1M w/85dB Elac's, I am locked into Class A only using Nelsons most important First Watt moniker... If the first watt doesn't sound good lol. 

I mention this as I am all Morrow level 3, except some power cables. Way broken in by their 400+ hour reccomendation.

Good luck!

I don't have the challenge you have.

I would encourage you to give Moon a listen.  

I had McIntosh tube pre and SS amp.  I upgraded to Moon 390 pre-amp/network player and M400 monoblocks.  I notice I feel like I'm listening to music at lower volumes only to realize I'm listening to peaks at 80+dbs and there's a quiet background with undetectable distortion resulting in multi-hour listening sessions several times a week.  

The amps are AB and the monoblocks are A for the first 10 watts.