Ashly Electronic Amplifier none User Manual

Page 7

Attention! The text in this document has been recognized automatically. To view the original document, you can use the "Original mode".

In a typical setup, power amplifiers can be run "full-on", with level control
being accomplished at the crossover. Adjust these controls for best system

balance. Note that horn and compression driver combinations are much more
efficient than cone speakers, often by 12-20dB. When cones and compression
drivers are used together, you should expect a much lower level setting for
the horns (all other factors being equal) to compensate for this difference
and obtain proper balance.

PEAK LED

Ashly crossovers feature a peak detection circuit which monitors signal levels

several

critical

points

the

crossover:

input,

filters,

and

outputs.

The

LED will flash when signal levels of +14dBV are reached anywhere in the
crossover. Since our crossovers have a nominal 20dB of headroom referenced to
a standard operating level of OdBY (.77 Volts), a flashing LED warns you that

you are only 6dB away from clipping.

Choice of a "nominal" system operating level is really up to the operator.

You may want to run the system "hot", with the peak LED flashing frequently,

or you may want to run the system more conservatively, with the LED flashing

seldom or never.

Obviously, the hotter your nominal level, the less system headroom you will

have.

For

initial

setup,

recommended

that

you

adjust

your

level

controls so that the LED flashes only on the loudest signal peaks, if at all.

Since peak levels are monitored at several key circuit points, the peak LED

can be used to isolate the source of any overload. If the LED flashes even
though all input and output levels are turned down, then the signal being fed

to the crossover is excessively hot. In most cases this means you should go

back and turn down your mixer. If the LED flashes when you turn the Input
level

control

(with

the

outputs

still

turned

down),

the

overload

occurring in the filter sections, and you should back the Input level down a
bit. If the LED first flashes when you turn the output level controls up,

then the overload is occurring in the output stage, and you need to turn the

output controls down.

OUTPUT LEVEL CONTROLS

Output

Level

Controls

Crossover

Frequency

Controls^

Peak

Input
Level

Rolloff

Figure 2 An SC-70 3-way crossover, showing front panel controls

generic to all Ashly crossovers.