Verified answer

I never heard of those. Are they 2N9014/5, 2SA9014/5 ??? Any manufacturer logo on them?

Edit:

OK. They are a close equivalent to BC549 and BC559. The only difference is that the pins are reversed. Looking at the pins with the flat on the top, left to right the 2N9014 pins go EBC, the BC549 pins go CBE.

Here are a couple of circuits:

http://www.circuitamplifier.com/mini-audio-amplifi...

http://elecproj.blogspot.com/2009/06/three-transis...

A mic preamp circuit that would work with the 2N9014s:

http://www.zen22142.zen.co.uk/Circuits/Audio/ecmmi...

9015 Transistor

Your amplifier circuit gives me another idea. You can just experiment it. Remove the 220 uf capacitor and connect it to the +12 volt line. (take care of capacitor polarity) Connect a speaker to this capacitor and to the junction forming 1 ohm resistors. Take another 220 uf capacitor and connect it to the - node of the amplifier.(remember the capacitor polarity) Connect a speaker between this capacitor and 1 ohm resistor junction. The signals in both the speakers will be out of phase. So the speakers have to be placed back to back. The above arrangement is only for experiment and the volume should be noted at changing location of speakers.

This is a challenging question, and one that made me curious for quite some time.