Nexo has finally sequelled its successful Geo S and Geo T tangent-array systems with the Geo D and Geo Sub, which as much as anything offer refinements implicit in previous models rather than breaking the mould: both Hyperbolic Wavesource and NX242 gain upgrades. Once again, the new generation "allows an unprecedented entry point" to line array technology, and it's the small-to-medium sized occasions that will get the benefit.