A good used pair of 100 watt tube monos to drive your SL3s will cost you $800-$1200. For that price you can buy VTL Compact 100s or Quicksilver Silver 90s. I have used both with Electrostic speakers with good results.
100 watt tube monos are very powerful and you can easily learn how to bias them.
100 watt tube monos are very powerful and you can easily learn how to bias them.