How to record very faint sound from the analogue input?

[marc]

Colin Law wrote:

> On 5 March 2010 18:59, Dotan Cohen <dotancohen at gmail.com> wrote:
>> I need to record a phone conversation, but the sound from the analogue
>> input is so weak that recording and playing back in Audacity I hear
>> almost nothing. How can I either boost the playback or (even better)
>> boost the input so that the file is recorded in a hearable way?
>
> This thread seems to me to be getting a bit out of control with talk
> of building amplifiers and so on.  Can we go back to the beginning and
> try again.  Where exactly is the signal coming from in the first
> place?  A quick glance back through the thread does not seem to
> discussed this, but apologies if I missed it.

I missed the start of this, but it sounds like an impedance mismatch. I
presume you mean the analogue output, btw.

Amplifying a crap audio signal, analogue or digital, simply brings the
noise floor with it, so you'll not get great results; although it
depends on your requirements.

-- 
Best,
Marc

"Change requires small steps."