[Iain Churches[_2_]]

Crowhurst stated that the signal generator being used in the
evaluation of an amplifier needs to have THD an order
of magnitude below that of the unit under test.

A fairly good PP tube amp can manage THD 0.05% at1W,
so we are talking about a function generator 20dB better
with 0.005%. i.e. -86dB

I share a workshop with several other amp builders,
and so there is no shortage of generators to choose from.
The modern ones do not perform as well as one would expect.

I am sure that there are models by HP that are better
but these may be beyond the budgets of most of us.

I have made some comparisons at:

http://www.kolumbus.fi/iain.churches...enerators.html


Iain