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BJT or CMOS amplifier, lower noise?

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ahgu

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I want to use either bjt or cmos to act as small preamp for an electret mic. in the ball park of gain of 10

probably use in common emitter configuration. Which one has lower noise?
and which part should I use for lower noise? part number?

thanks
Ahgu
 

flatulent

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Try JFET

Try a JFET. They have lower noise in the audio region than either MOS or BJT. The U301 or J301 will work well.
 

arturt134

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Please tell me who manufacture this amplifiers?
Thanks in advance.
 

flatulent

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discrete transistors

These are discrete transistors. Many companies make them.
 

ahgu

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differential preamp with 2 jfets?

how can I make a diff jfet amplifier? want to min the noise.
using 2 jfets.

thanks
ahgu
 

ahgu

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diff jfet amp

with device matching , I wonder if it is actually better to use 2jfets, WRT just one jfet.
 

flatulent

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doubled noise

You will get double the noise. The topology is the same as BJT or MOS amplifiers.
 

Borber

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bjt

Transistors BC550 NPN F=0.6dB at Ic=200uA Vce=5V f=15Hz-15kHz
BC560 PNP F=1dB
can be used.
 

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