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Lawrence Statton XE2/N1GAK · February 13th 07, 07:03 PM posted to rec.radio.amateur.homebrew

writes:

Hello,

I have been looking around the web for a complete kit for an audio
amplifier, for a circuit that I am building that needs to have a wide,
flat as possible frequency response (0Hz - 100Khz). Need to be able to
bring 400mV up to line level. I have seen several kits based on a
LM386, but I can't find any specs that show that circuit is reliable
beyond 20hz - 20Khz. I am a beginner, so keep that in mind when
responding.

-Scott, WU2X

Who's definition of line level? For consumer audio gear, line level
is 0.1 milliwatt into 1000 ohms, or roughly 320mVrms. If your source
impeadance is sufficiently low (most gear has input impeadance in the
several-thousand ohm range), you're done.

If you need it for studio gear, then you've got to get your singal up
to 2.5 milliwatts into 600 ohms, or about 1.2 Vrms, and any of a
million op-amps can give you the gain you need to reach those levels.

The ubiquitous 741 is cheap and easy to use, but the now 40-year-old
design is kinda noisy.

I cannot imagine that a 386 would be a good match just because it's
designed for much lower output impeadance and much MUCH higher levels.

--
Lawrence Statton - m s/aba/c/g
Computer software consists of only two components: ones and
zeros, in roughly equal proportions. All that is required is to
place them into the correct order.