Amplifier with different output (CB9057E)

This circuit was found in a 70s National Semiconductor manual. It has a different output way for coupling to the speaker.

Standard 1 MHz Oscillator (CB9653E)
We found this circuit in an old American documentation. Transistors can be modern equivalents. ...
Differential Amplifier (CIR18634E)
In the figure we have the conventional configuration of a differential amplifier with the...
LM12 in Parallel Amplifier (CB14389E)
This 8 A high output power amplifier uses two National Instruments LM12s. The maximum capacity of the...