Shahinian Oblisk


I have just purchased a McIntosh Tube Amp 2102 and Tube PreAmp 2200. The amp gives a choice of connecting my Shahinian Oblisk speakers to different OHM speaker settings.
1. Can someone please explain how the OHM effects the speakers.
2. Should I choose a higher or lower OHM setting for the Shahinian speakers.

Thank you in advance for your assistance.
kgksecurity
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As a fellow Shahinian-McIntosh-owner, my experience is that the Obelisks sounds best with the 8-ohm-tap
Speaking of Obelisks...
While this doesn't have an exact bearring on the specific question, if you go over to audio asylum and do a search on these speakers, there's a discussion from a year or three ago re. the unique design approach Shahinian takes with them and his Diapasons.
If I understand correctly, the Obelisks purposely use the acoustics of the listener's room to enhance a life-like presentation of the music. Since the actuall room is therefor in a way part of the speaker, I wonder what the ideal listening space for them would be with that in mind.