What is a preamplifier?
What
is a preamplifier? It could be difficult to tell, the official explanation was
below.
A
preamplifier is the role of audio amplification, generally because audio
signals are very small and cannot drive power amplifier directly, you must
install a front voltage amplification circuit to amplify signal then drive
power amplifier. Also, due to the diversity of input signals, such as input
signal voltage level, as well as high and low input impedance, a preamplifier will
fit to the strength of the input signal to set up a different magnification time.
And if internal resistance doesn’t match between signal sourcing and amplifier,
it makes to lose a dynamic frequency response, details! Besides adjusting the
volume, active preamplifier also can be used for preliminary amplifier, reduce
internal resistance difference between the signal sourcing and power stage,
which is used as a buffer.
Finally,
because varieties of users have various audio sources, output signal amplitude
and impedance that less people actually study, there is a big difference at
listening actual sounds, on the one hand it is audio output signal amplitude is
different, on the other hand is internal resistance mentioned above. This has created more songs
we heard was substantially compress it’s dynamic, and detail is lost, frequency
response is attenuated. Very apparently we were using computer or cell phone to
connect power amplifier when listening to some music, it doesn't even feel to
the low frequency and high frequency is not so bright small volume situation.
No matter how good computer sound card and how good the sound system, it could
not find the original tapes of the time!
Here,
6N2 tubes we used the most common one, we specifically tune the circuit for computer
sound source without expensive components piled up, but a reasonable
configuration, we choose the most suitable work point, and precisely matched the
key components to ensure circuit work at the best.
Circuit Diagram
More details, please find here!