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Passive amplifier with a transistor? Answered

It's possible to build a passive amplifier with a transistor? i have think about something that might work with a capacitor conecting the audio + to the transistor base. not sure if will do, and if it do i don,t know how much resistence is needed on the other end of the circuit.
also i'm going to use 2 15 ohm speakers in series.

5 Replies

Jack A LopezBest Answer (author)2012-03-21

I think you are using the word "passive" incorrectly.  But ignoring that, it is possible to build a crude amplifier with a single transistor.


However, I think if you want something that actually works well, it would be worth finding the whole audio amplifier circuit as a module, sort of like the amplified-speakers they sell for connecting to the sound card of a desktop computer.

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steveastrouk (author)2012-03-21

You can't HAVE a "passive" amplifier. By definition !

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Re-design (author)steveastrouk2012-03-21

I don know, I've has some amps that were pretty "passive".

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mpilchfamily (author)2012-03-21

No. In order to amplify an audio signal you need a power source and an audio amplifier.

Why 2x 15 ohm speakers in series? That gives a total impedance of 30 ohms meaning they won't be as load as they could be hooked up in parallel. If you want the speakers to be loader then hook them up in parallel.

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