Budget SS integrated with great timing and immediacy up to 2k used?

I have heard immediacy and great micro dynamics in class A amplifiers only (especially single ended). I don't care for class D amps. Are there any classic class AB amps with good immediacy and microdynamics? I have efficient speakers but with low impedance down to 3ohm. So 25W in 8 Ohm / 50 in 4 ohm would be sufficient.
You might like the Rega Brio.  I've heard a lot of ss amps in my system and that one came to mind when reading your requirements.
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If you can be patient, look for a First Watt push/pull model in the used market. Meets your requirements and some and is a good investment.