I have had the A-S2000 and currently use the A-S2100
Both are great integrated amps. Yes the 2100 is smoother. There is also more bass heft to the 2100. I have had all kinds big name gear to compare and the 2100 is as good or better in many cases to components from Cary etc. Yamaha did an excellent job designing an Integrated that can go head to head with anything under 10k. The A-S2000 is also extremely good considering its quite low price in comparison.
I also had an A-s500 and A-s700 in my workshop system. The 700 was oassable but the 500 was not. Obviously those are much cheaper units and good compared to the big box junk for more $ but not Hifi.
The 2000 is excellent and the 2100 is superb. I powered Dynaudio C1 with the 2100 and it was fantastic. Currently powers Sonus Faber Liuto and has a great tight control on the low end. The only thing I didn't like about Yamaha they have now fixed. If you needed service their warranty depots sucked. Now they offer 10 years on these and anything wrong in the first year means new unit, not refurb like they used to do.
Both are great integrated amps. Yes the 2100 is smoother. There is also more bass heft to the 2100. I have had all kinds big name gear to compare and the 2100 is as good or better in many cases to components from Cary etc. Yamaha did an excellent job designing an Integrated that can go head to head with anything under 10k. The A-S2000 is also extremely good considering its quite low price in comparison.
I also had an A-s500 and A-s700 in my workshop system. The 700 was oassable but the 500 was not. Obviously those are much cheaper units and good compared to the big box junk for more $ but not Hifi.
The 2000 is excellent and the 2100 is superb. I powered Dynaudio C1 with the 2100 and it was fantastic. Currently powers Sonus Faber Liuto and has a great tight control on the low end. The only thing I didn't like about Yamaha they have now fixed. If you needed service their warranty depots sucked. Now they offer 10 years on these and anything wrong in the first year means new unit, not refurb like they used to do.