[![enter image description here][1]][1]


[![enter image description here][2]][2]


Goal of the circuit:

 - Must be able to deliver 1.5 W to the speaker (8 Ω) at 1 kHz.

**First Problem**

1.) how can we drive an 8 ohm speaker if it can only support around 1.5-2 watts? Because when we input 8ohms as the load the Vout decreases.

 - Coupling capacitor formula we used is
1/2pi(lowest frequency)(resistance seen by capacitance)
20Hz was the lowest frequency I used.

[![][3]][3]


Referencing to the image above. If we add a common emitter by our understanding it should increase the power but even with coupling capacitor, it won't shift down to AC.

The next step we did was thinking of adding a darlington pair, it did increase the gain, but it still doesn't want to make the AC waveform shift down to its negative half cycles for a safer speaker usage.

[![enter image description here][4]][4]


[![][5]][5]


above is the darlington w/ ce and ef (1s)

[![enter image description here][6]][6]


above is without the darlington.

**Summary** 

Our goal is to get the output that is the same in the photo below. **note** The RL (R6) is 100K ohms but we want that output if our desired Load is an 8ohms 2W Speaker, that can ultimately support 1.5-2W power for the speaker. **What changes can we implement in our design to achieve this?**

[![enter image description here][8]][8]


  [1]: https://i.sstatic.net/xHudZ.png
  [2]: https://i.sstatic.net/1zzzx.png
  [3]: https://i.sstatic.net/uSUxQ.png
  [4]: https://i.sstatic.net/AF6RA.png
  [5]: https://i.sstatic.net/2brAa.png
  [6]: https://i.sstatic.net/cTcmm.png
  [7]: https://i.sstatic.net/TOkSM.png
  [8]: https://i.sstatic.net/u5vYT.png