Michael Gerzon's 3-speaker stereo, Trifield, isn't a direct use of ambisonics as such, but it uses some principles from it (e.g. Use of shelf filters to help give a more consistent energy with frequency distribution over the stereo front sector and to stabilise it when the speaker angle is larger than 60 degrees). The out of phase component is what appears in the rear/side speakers in Meridian's implementation (Haffler). Effects will vary quite a bit between recordings, giving more or less output from rears and sides, and giving very different effects depending on how the recording was made using different microphone and/or mastering techniques.

You could experiment with acoustic recordings utilising coincident crossed fig 8 microphones and Pro Logic material, which would both contain more out of phase components than spot mic and stereo panned stuff. Ambisonic UHJ recordings may work quite well, or at least interestingly, with Trifield. The problem is that mic techniques are very rarely stated. It's no wonder we struggle to decide what DSP method and settings sound best to each of us.

G61RSL, G98-DH, G01, Quad 606, Quad 306 (x3), Quad-ESL63 (x 2 pairs, F&R), KEF LS50 (S), Quad 10L sub, Martin Logan Motif (CF) + miniDSP