OK, after reading this article I have come to the following conclusions and I am asking all of you if this would be your conclusions as well.
1) Under the "Channel Calibration" menu on the 990 set the subwoofer to -15db, the lowest setting.
2) Then on the SMS-1 when doing the initial level set for the test volume use the 990 volume to set the right side of the curve.
3) set the SMS-1 volume some where in the mddle to allow both up and down adjustments, say 15.
4) Use the SUB's volume to set the left side of the curve.
If I understand the article correctly it is suggesting that if the input signal to the SMS-1 is to large it will cause a disproportionate amount of distortion the lower the frequency goes. However at lower input levels the distortion can be kept to 0.1 to 0.2% which is not great but certainly better than the results shown when using a larger input signal to the SMS-1.
Has anyone out there heard this distortion in real life? I tried a couple of simple tests and although I thought that it did sound better at lower input levels to the SMS-1 I felt that it was no where near the kind of difference that was shown in the referenced article above.
I am curious as to what others think about this situation as this is the only article that I have ever seen giving the SMS-1 any kind of bad rap.
Thanks in advance for your comments,
Emotiva XMC-1, Outlaw 7500, Sonus Faber Olympica III Fronts, SF Liuto Center, SF Surrounds, LFM-1 EX, Oppo BDP-103D, Apple TV (Gen. 4), Mitsubishi 65" Diamond DLP, Outlaw Cables, PS Audio Power Quintet, Duet and power cords.