Lucius1958 wrote:As for the bass, that's more a function of the horn's length than its position.
It is actually the opposite, I'm afraid. When a horn is placed in a corner formed by three walls the low frequency response is greatly extended in comparison to the same horn placed at the dihedron of two walls (or a wall and the floor), which in turn delivers an extended low frequency response in comparison to the same horn placed suspended in the center of a wall, which again in turn has an extended low frequency response in comparison to the same horn placed suspended in open space, which is the worst case scenario.
As already said, however, you'll have a hard time handling a tabletop gramophone placed on the floor in a corner.
About its height in reference to the listening ears, all horns are directional to some degree, and more or less all of them have a sonic "focus" point which, unless the horn has complicated shapes (asymmetric, split, re-entrant and so on), is usually approximately in front of its mouth. If you put your ears in the focus point, you should distinctly hear that the sound has more detail, just as if it was being played inside your head, or with a "headphone" effect.
Wether you would like to listen to the gramophone by standing in the focus point or elsewhere is a matter of taste. It tends to be more emotional when the record is fine, but it also tends to enhance defects and hiss of the record when the grooves are only so and so. High frequencies tend to be emphasised, also, which may feel exciting at first but may rapidly lead to listening fatigue. In other words, you have to try to move around the focus point and see what fits your taste better: there is no written rule, and each gramophone model sounds different too.
As a final note, if you place the gramophone on the floor in a corner, the focus point will also approximately be at floor level, which will make hearing quite uncomfortable.