- Joined
- Jan 17, 2017
- Messages
- 105
When NIMBUS produced about a dozen or so MLP DVD~A 4.0 discs some years back, those expecting discrete elements in the rears from these former UHJ Ambisonic masters might be a tad disappointed. They contained Ambience, only.
My Meridian 861 Pre~Pro has a built in Ambisonic decoder and all those NIMBUS UHJ RBCDs played through it contained ambient only surrounds!
It’s not so much that only ambience was encoded on the rears, as all speaker signals in ambi contain information for the reconstruction of the horizontal 2D soundfield. Those discs had pre decoded UHJ speaker feeds (G-Format) in them, which were from performances where the ambisonic mic would have been facing the usually arrayed sound stage/orchestra at the front.
Sadly, Nimbus did not make the B-Format archives that would have made better G-Format releases. They often recorded straight to 2 channel UHJ. In principle, had full B-Format been used, primary sound sources could have been at any angle *and* been as well defined and spatially/tonally stable on playback as the front.
Nimbus still concentrates its attention on classical & world music, which is performed pretty much all with orchestra/ensemble at the front in great performance spaces. What goes on at the rear and sides of the soundscape will be then mainly reflections etc (ambience). Quadrophonists are used to thinking in terms of using rears as voices for sources whereas ambi is a full 2D or 3D sound scene description.