The most recent installment of [Dino Segovis’] Hack a Week covers the construction of a simple NPN transistor audio preamp. Some time ago, he built a small audio amplifier using an LM386 which worked well, but didn’t quite get his music as loud as he would like it. He decided to build a preamp to complement his amplifier, and demonstrates how you too can build one with just a small handful of components.
As the name probably suggests, the cornerstone of this amplifier is an NPN transistor. He explains that a forward bias is applied to the base-emitter junction, which results in the transistor operating halfway between its cut-off and saturation regions. Both halves of the input audio signal are superimposed on this bias voltage, resulting in a decent amount of gain across both channels from a relatively small package.
The preamp isn’t going to win any awards among audiophiles, but it is definitely a great beginner project. Its a novel way of demonstrating how transistors work, while producing a useful takeaway piece of audio equipment at the same time.
Continue reading to see a video showing just how big an effect [Dino’s] NPN preamp had on his music.
Filed under: classic hacks, musical hacks
Posted on Sat, 06 Aug 2011 22:00:04 +0000 at http://feedproxy.google.com/~r/hackaday/LgoM/~3/SGm2-IZXZ-8/
Comments: http://hackaday.com/2011/08/06/quick-and-easy-audio-preamp/#comments
As the name probably suggests, the cornerstone of this amplifier is an NPN transistor. He explains that a forward bias is applied to the base-emitter junction, which results in the transistor operating halfway between its cut-off and saturation regions. Both halves of the input audio signal are superimposed on this bias voltage, resulting in a decent amount of gain across both channels from a relatively small package.
The preamp isn’t going to win any awards among audiophiles, but it is definitely a great beginner project. Its a novel way of demonstrating how transistors work, while producing a useful takeaway piece of audio equipment at the same time.
Continue reading to see a video showing just how big an effect [Dino’s] NPN preamp had on his music.
Filed under: classic hacks, musical hacks
Posted on Sat, 06 Aug 2011 22:00:04 +0000 at http://feedproxy.google.com/~r/hackaday/LgoM/~3/SGm2-IZXZ-8/
Comments: http://hackaday.com/2011/08/06/quick-and-easy-audio-preamp/#comments