It's definitely an Echo series speech synthesizer card, using Texas Instruments LPC speech. The TI chip labeled "ECHO-2" is the actual speech chip.
There were several versions of the "Echo" card made, this is either just one of them, or a private-labeled version. I don't know - that's a guess.
There is plenty of information about these cards on the web, just google something to the effect of "Apple II Echo Speech" and see what comes up.
Some of these cards can be pretty pricey - nice find! I'm a huge fan of TI speech. Major 80's connection there
Chris