Category Archives: audio

Long-tailed-pair oscillator

I needed a quick alarm tone generator for a piezo speaker, and with no 555 at hand, this turned out to work quite well, and it’s just as small. It operates with just a few mA current. It is a … Continue reading

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More TEF6606 info

For the circuit that was constructed for testing (based on the Application circuit in the data sheet, the v3 copy of the datasheet is here), the TEF6606 was powered directly via a 9V alkaline PP3 battery (not ideal, because the … Continue reading

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Simple op-amp based headphone amp

This single-IC circuit is pretty basic but is enough to get the TEF6606 audio up to (very loud) headphone levels. It is just a test circuit, not intended for high quality. There is no volume control, so the volume is … Continue reading

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Electret mic amp

High sensitivity (36dB gain), tested for low harmonic distortion and flat frequency response (1dB down at 40Hz, flat past 30kHz). It was intended for recording outdoors, with the electret element in a rubber washer, within a 15mm diameter PVC tube, … Continue reading

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Audio boards (for sale)

This board is a generic audio controller with decent sound. It was designed for an ipod but can be used with other devices. It can be used to connect an ipod to a car or home hi-fi for example. There … Continue reading

Posted in audio, ipod | 1 Comment