atmosphere, I had an Electron Kinetics Eagle 2 on the bottom of the 4a's. Your amps while sonic champions in the midrange, suck in the bass department.I've had the Eagle in my own system at home. I can see why people liked it at the time- as solid state amps of the period went it was pretty smooth (but not as smooth as a good tube amp). But as to playing deeper bass- on my speakers (Classic Audio Loudspeaker model T-3; flat right to 20Hz) I found myself turning up the volume to try get more impact out of the Eagle - despite its power and the 98dB efficiency of the CALs, the Eagle simply couldn't match a set of our M-60s in the bass department - on that speaker.
Different speakers might and will get different results. If you sold our gear, you would know how important getting the right match is. For this reason, I suspect that you didn't sell our gear at all. At best, my suspicion is that you had a trade-in and simply didn't know how to show the amp off in its best light. None of the ARC stuff of that period could really play the bass right; IMO it didn't have the bandwidth needed (full power to 2 Hz).
This is easy to suss: what dealership did you work for?