Below is a french do it yourself project for connecting a [[SP0256]] speech chip to a printer port, using Data, Strobe=ALD, and BusyAck=Status.
It isn't actually a CPC project (for the CPC one would need to replace LPRINT by PRINT #8) (and the CPC's printer port has only a Busy pin, no Ack pin), aside from that, it should be compatible with the CPC printer port (the CPC's GNDed D7 printer bit is no problem, since allophone numbers are only 6bit wide).
No idea what the 74374 latch is intended for, the printer port output should be latched anyways, so it seems to be totally useless.