I made a preamp using circuit from hackaweek in my early diy days.
But I am wondering if this pre amp can be made better.
The Single NPN Transistor Audio Preamp | HACK A WEEK
I think their should be a resistor between base and emitter.
But I am wondering if this pre amp can be made better.
The Single NPN Transistor Audio Preamp | HACK A WEEK
I think their should be a resistor between base and emitter.
Better for what purpose?
This preamp has moderate gain (probably too much for many purposes), lowish input impedance, highish output impedance, and very high distortion. It is merely a 'textbook' preamp for newbies; useful for initial learning about transistors, but almost useless for any real purpose.
This preamp has moderate gain (probably too much for many purposes), lowish input impedance, highish output impedance, and very high distortion. It is merely a 'textbook' preamp for newbies; useful for initial learning about transistors, but almost useless for any real purpose.
Can I know a circuit to do it?If you want to use only one transistor
there are some better ways than that.
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I want to pair with LM386 for a small boy.
He want to build his own good amp with preamp.
The LM386 can have plenty of gain, so no preamp is needed, just a 10k volume control.
See figs. 10, 12, and 14 here. http://www.ti.com/lit/ds/symlink/lm386.pdf
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Thanks I am going with no pre amp.
But I still want to build a preamp to show him something .
Sure, the preamp could also be an op amp instead of a transistor.
It's easier to understand.
Then I should go for opamp.
I have my own preamp with bc547 but it is too complex to explain to a 9year old boy.
The op amp is good. You can use a plug-in socket with it in case of damage.
There are plenty of pcbs ready to hook up or build, on ebay.
It's best to use a 9V battery for the preamp, instead of a line operated supply, for safety.
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I am using breadboard. His mother will kill me if I show him soldering iron.
Yes, I was going to suggest that, it's very easy. Even the 9V battery leads can plug right in.
It would have to be a single supply circuit.
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TL071 seems to be good one to explain to a beginners.
Any common op amp will be fine for your purpose. A single package type will be less confusing.
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