Page 8
Orfeo 60
Owner's Manual
Amplifier Power and Loudspeaker
Selection
The
Orfeo 60
has a nominal power rating of 60
watts for each channel. While this may seem
like a low power output compared to many
amplifiers on the market, because of the class
A operation, the low distortion, wide power
bandwidth, and the grace that these amplifiers
have when overdriven, they will produce as
much or more level sound than many 100 watt
amplifiers. We suggest that you consider any
loudspeakers with average rated sensitivity of
85 dB/Watt/Meter or greater. Greater
sensitivity will allow higher listening levels
before either the amplifier or the loudspeaker
runs out of steam. Remember that with most
speakers in even a relatively large room the
amplifiers will be operating at average levels of
only 1-5 watts each with typical music at quite a
high average sound level of 90 to 95 dB.
We have successfully used the
Orfeo 60
with
many types of loudspeakers, including dynamic
cone, planar magnetic and electrostatic types.
When choosing a loudspeaker many variables
come into play, therefore we will not attempt to
recommend a type or set of 'brands' which you
should consider. Our suggestion is that you
work with the dealer representing the
Orfeo 60
and choose a loudspeaker which works well for
your tastes, in your room with your system. A
dealer which sells the
Orfeo 60
will be more
than competent to guide you in your selection.
Amplifier Placement and Power-on
When installing the amplifiers it is important
that they receive adequate ventilation. Allow at
least 6 inches above the amplifiers, and be
certain that the holes on the bottom cover are
open to air circulation (do not place them
directly on a thick carpet, as this will block the
bottom ventilation holes). Do not use the
Orfeo
60
in a closed cabinet unless fan cooling is
allowed or the amplifiers will overheat and could
be damaged. They generate consider-able
heat in operation because of their single-ended
class A operation. With adequate ventilation on
an open shelf or stand they will cool themselves
through convection and will not require any
additional cooling.
When the setup is complete and all
connections are made, the power cord can be
installed and the power switch turned to the 'on'
position. The amplifier may produce a brief
'hum' noise through the loudspeakers as it
warms up. This should less than 1 second.
The amplifiers will be operational within 15
seconds, and they require only 15 to 20
minutes to reach optimum performance. There
will be a short break-in period of 20 to 30 hours
when the amplifiers are first used. The sound
quality potential will improve during this period
as all of the components and tubes 'settle in'
during this time. Further improvement in sonic
performance will occur during the first 100 to
200 hours of use as the copper wire anneals
and all of the components settle in.