The double Dyck path algebra Bqt was originally introduced by Carlsson, Gorsky, Mellit in search of a geometric realization of the similarly named Aqt algebra arising in the proof of the Shuffle Theorem. In this talk I will explain how the elliptic Hall algebra arises as the spherical subalgebra of Bqt. If time permits, I'll discuss how an algebra Bqt(Q) may be defined for arbitrary quivers Q whose spherical subalgebras, conjecturally, recover the K-theoretic Hall algebras of Q. This is based on joint work with José Simental and Eugene Gorsky.