Woody wrote:
A mistake that many people make with lo-Z headphones is to run an amp
straight into them and then wonder why there is so much residual
noise.
The easiest method is to use a small power amp such as a LM386 or
TDA2003, then put a resistor in series with it - something in the
range 330-470R will usually suit. You will probably end up with a far
more acceptable result as the amp is specifically designed to drive
audio rather than just a general purpose amp.


Yes, I appreciate that a proper audio amp would do the job better. But I had
a spare amp section on the quad op-amp so I thought I would try to use that
before looking at other options.