Thieliste - I don't have 3.7s, but can speak in general to your listening angle question. I believe the biggest factor is the room. Jim designed all the floor-stranders to be fired straight ahead if the room can support that. Their cross points are unusually low to better balance the in-room power response with the on-axis direct response. Add the fact that drivers usually have some hot-spot beaming directly on axis - their smoothest response is around 15° off axis.
That said, nearly everyone uses them with the focal point somewhere behind your head, perhaps 5 to 10° off axis. Notable exceptions include the Thiel listening room and Tom Jung's mastering room with CS5s. Thiel speakers with their long, slow roll-offs exhibit less than perfect FR graphs, which are decidedly smoother and flatter at 15 to 20° off axis. I believe the discrepancy is that most rooms have side walls too close and too reflective to properly support Thiel's wide polar pattern. Those reflections are more onerous than the FR hot-spots on axis.
I suggest that you might try bringing the speakers closer together, perhaps 7' or even 6' C to C, and fire straight or nearly straight ahead. A 10' from baseline listening distance puts your listening angle at the 15 to 20° sweet spot. If the sound is less harsh when toed in, try instead putting some absorptive or diffractive material on the mirror-spot on the side wall. At best you can get greater image width, solid center fill, and smoother frequency response with no down-sides.
I realize I'm going against common wisdom that the wider the stance the better. In a large room like Thiel or DMP, you can get both. 9-10' spread and straight ahead with 12' listening distance approaches ideal in my experience. But smaller rooms reduce possibilities. In my opinion, most people toe in when the might be better served by narrowing the stance.
That said, nearly everyone uses them with the focal point somewhere behind your head, perhaps 5 to 10° off axis. Notable exceptions include the Thiel listening room and Tom Jung's mastering room with CS5s. Thiel speakers with their long, slow roll-offs exhibit less than perfect FR graphs, which are decidedly smoother and flatter at 15 to 20° off axis. I believe the discrepancy is that most rooms have side walls too close and too reflective to properly support Thiel's wide polar pattern. Those reflections are more onerous than the FR hot-spots on axis.
I suggest that you might try bringing the speakers closer together, perhaps 7' or even 6' C to C, and fire straight or nearly straight ahead. A 10' from baseline listening distance puts your listening angle at the 15 to 20° sweet spot. If the sound is less harsh when toed in, try instead putting some absorptive or diffractive material on the mirror-spot on the side wall. At best you can get greater image width, solid center fill, and smoother frequency response with no down-sides.
I realize I'm going against common wisdom that the wider the stance the better. In a large room like Thiel or DMP, you can get both. 9-10' spread and straight ahead with 12' listening distance approaches ideal in my experience. But smaller rooms reduce possibilities. In my opinion, most people toe in when the might be better served by narrowing the stance.