Speaker resistance?

Last time I checked, a PCB speaker was not expected to provide power or fidelity. Hence, I wouldn't worry about power wasted in connecting a resistor in series with an 8-ohm speaker to increase the impedance presented to the driving source and certainly not worry about the damping factor being ruined by the extra resistance. PCB speakers are usually there simply to indicate that something is happening -- when was the last time anyone really needed to hear the subtle dynamics, transparent clarity and other audiophool characteristics through the speaker mounted on an old dial-up modem board? If you need fidelity and power, you'll be using external speakers.

The world will not explode if you try driving an 8-ohm speaker directly from the output of the chip. The chip may, but maybe not. What's to lose other than a few bucks. If not specifically designed for driving the low impedance, I wouldn't do it if the design was going to be replicated 50,000 times for retail sale. But if it's just for you, who cares if it doesn't pan out?

Dean

The IC is a high quality MP3 player and Mpeg-4 steaming audio player. I don't think it is used to hear just little beeps.

The application note shows a stand alone unit with 0R0 jumpers in series with the 30 ohms headphones.
It is a tiny little surface-mount IC that might melt if it tries to drive 8 ohm speakers.

My old 486 pc has pretty small 2"x1" speakers each in a tiny little bass-reflex plastic enclosure. The enclosures are very small and are ported for extended "bass" response. They don't produce earth-shaking bass like a sub-woofer but they do a pretty good job with the bass in background music.