In the meantime, the onset inlet could be a signal, and the phasor could just be set up like this since onset is just a sum:

[phasor~]

| \

|  \

[*~ size/2]

|    \

|    [*~ size/2]

|    |

[tabread4~]

|

64-bit output

I made a version of nusmuk's tabread4c that does this

-Sebastian