john reves wrote:

I read somewhere that a voltage reading from a voltmeter is different from
the reading taken when something is 'under- load'.

With an unregulated, low current power supply you will find the voltage
sags as the current draw increases. And, normally, with these cheapy
wall-warts the actual voltage is *higher* than labelled as a) they're
cheap and innacurate and b) they expect the voltage to sag down towards
the indicated value. I've not come across any before where the voltage
starts off lower but it falls in with a) above.


Would you use the 9 volt setting (which reads 7.5v) or use the 12v voltage
setting which reads 10volt, for use with this 9volt amplifier. Thanks for
advice.

Like as not 10v will be fine (but as said, 7.5 is a safe starting
point.) It's rare for any device to require an exact voltage unless it
uses 5v TTL ICs and doesn't have any sort of on board regulator.

--
Scott

Where are we going and why am I in this handbasket?