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Step 15Controlling Gain -- Elegant Way
The gain of the LM386 amplifier chip is controlled by a resistor (and capacitor) between pins 1 and 8. I replaced the toggle switch with an ALPS RK097 10K ohm stereo audio taper potentiometer with power switch from Tangent's Parts Shop (and available nowhere else, it seems). I used one of the two potentiometers to control the resistance between pins 1 and 8 on the LM386 and the power switch to control the power.
The effect of this change is that with the gain turned all the way up (resistance as low as possible), the ATS is quite loud and with the gain turned all the way down (resistance as high as possible) the ATS is somewhat louder than with no modification at all. In any case, both the easy and elegant modifications place the burden of amplification on the LM386 and the sound is considerably better at higher volumes.
The effect of this change is that with the gain turned all the way up (resistance as low as possible), the ATS is quite loud and with the gain turned all the way down (resistance as high as possible) the ATS is somewhat louder than with no modification at all. In any case, both the easy and elegant modifications place the burden of amplification on the LM386 and the sound is considerably better at higher volumes.
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Also, I was considering attaching a LED so that it flashes with the music. Would I be able to fit it (and the larger battery that I would need, I assume) in the tin?