You did not mention how long you had the 1.6's. If they are "new" or have not broken in yet, the bass is pretty much absent in my experience. I have 1.6's connected to a McIntosh MC300 with 300 wpc. It took a year and a half of what was for me, a lot of playing, before the bass came in beautifully and balanced the mids and highs. I have dismissed the idea of adding a sub because the bass is definitely fully there (to my ears anyway). You will get your money's worth from any MAC amp that puts out at least 50 wpc. However Magnepan told me their speakers perform well with more current, so I purchased an amp with more power.I agree generally with everything said above, especially taking an opportunity to test a new amp in your system. McIntosh can be expensive. If that is a consideration, be sure to check out Audiogon. I got a great deal there.
