You can buy a horn speaker, they are used outdoors on a PA system. The horn matches its small vibrating part to the air better than an ordinary speaker and the horn directs and concentrates its sounds in one direction so it is much louder than an ordinary speaker.I was planning to incorporate a horn of some sort for amplification as was suggested earlier.
The 0.1uF capacitor is missing. Use it because it prevents the IC from oscillating at a high frequency.So i guess i'll ask some more direct questions regarding the BTL app notes.
1.Why is there no ceramic decoupler on the BTL Vin. vs. the stereo setup?
They are all built into the IC.2. Why isn't there a single resistor used anywhere?
To reduce the gain, add a resistor between pin 9 and the capacitor it shows on pin 9. It will probably oscillate at a high frequency if the gain is too low and they should tell you that.3. The app notes mention using a resistor to limit gain, where and how would that implemented?
The datasheet has an error on the BTL schematic because it wrongly shows pin 5 as pin 6.
The insulated wire is for the signal and the shield is connected to the amplifier's ground.4. not related so much to the schematic, but in a mono setup, I can see the input which I assume is the insulted wire contained in the 2 wire mono jack.
Where does the second un insulated wire connect? common ground w/ the power jack?
Will you mix the input stereo channels together or just use one channel?