YORKVILLE AP6020, Owner'S Manual

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Modes
The AP6020 can be configured for Bridge , dual-MONO or STEREO
operation via the rear panel MODE switch. The following is a descrip-
tion of each mode:
Mono Mode
• Channel A & B inputs are paralleled.
• Each gain control adjusts the signal level for its respective
channel,
• Output signals are of equal phase.
• Two loads are driven.
• Loads are connected between the BLACK and RED post on
each channel.
Stereo Mode
• Two independent amplifiers, Amp A and Amp B .
• Two loads are driven.
• Loads are connected between the BLACK and RED posts on
each channel.
Bridge Mode
• Channel A & B inputs are paralleled. GAIN B has no effect.
• Output signals are equal in amplitude but opposite in phase.
• One load is driven.
• The load is connected between the two RED binding posts. The
BLACK posts are not used.
Subsonic Filter Switch
The
AP6020
features a specially designed subsonic filter that effective-
ly blocks potentially destructive energy in the band below 40 Hz. The
filter provides a 12 dB/octave. skirt below 40 Hz. It is implemented with
a two-pole network designed to minimize phase shift down to 40 Hz.
We recommend using this filter in conjunction with some subwoofers
and with all high power full range cabinets. With the filter disabled, the
AP6020
is flat down to 20-Hz, and rolls off at 12dB/Oct below that.
Limiter Switch
With the internal limiters activated, the AP6020 ’s gain is continu-
ously adjusted to fit the signal within the available dynamic range.
Occasional clipping is permitted. The limiters will not only help to
protect your system’s horns and tweeters, but will automatically make
the best use of the available dynamic headroom. With the limiters
activated, all you need to do is turn up the signal level until you start
to see some clipping. The limiters will make sure that you are getting
the maximum clean power output at all times. Setting the switch to
the IN position completely disables both limiters.
Protect LED
In the event of a shorted load or a load which is of too low an imped-
ance for the amplifier to handle the PROTECT LED will flash alter-
nately on and off at about 3 second intervals. The sound may come on
and off at ½ second intervals. In this case, the fault is in the speakers
or the speaker cables and should be located and remedied. No reset
of the AP6020 is required to restore proper operation. The PROTECT
LED will stay on if the amplifier has overheated. Check the speaker
load impedance and any restrictions to air flow at the air intake or
exhaust vents of the amplifier.
Short Circuit Protection
The AP6020 is fully protected against all possible passive load condi-
tions. It can operate into a dead short continuously without damage.
(However, we don’t recommend that you short your AP6020 “just for
fun.” Shorts do create a lot of stress on the output devices). The output
stage uses a unique triple slope VI-limiting scheme which is sophis-
ticated enough to remain inert during transient currents in excess of
150 Amperes and phase angles of more than 45 degrees. It is capable
of protecting the output stage from damage due to accidental short
circuits and improper loads.
DC Protection
In the unlikely event of the AP6020 ’s outputs going DC , a thyristor
circuit will short the output terminals and divert all potentially harmful
currents away from your speakers.
Thermal Protection
In the unlikely event that the AP6020 overheats, the signal will be
sporadically cut off and the PROTECT LED will stay on. The AP6020
is designed and tested to operate under “worst case” conditions with-
out shutting down, so if you experience a thermal shut down you
should check for blocked air flow.
Cooling
The fan draws air in from the front and expels hot air through the
rear vents. This is compatible with most installations. Since hot air
rises, the heated air forcibly expelled from the back tends to rise away
from the equipment rack. This draws cool air from the floor upwards
into the front of the rack. In some cases where the rear of the rack is
obstructed, it may be necessary to install rack fans to aid cooling. If
there are no obstructions, no secondary cooling is required.
Clip LEDs
The CLIP LEDS on the front panel will visibly indicate any signal
excursion beyond the dynamic headroom of the amplifier.
Reliability
The AP6020 is designed and manufactured by Yorkville Sound . Each
unit undergoes a thorough, temperature cycled burn-in period, and
each circuit is tested by both manual and sophisticated computer
controlled equipment which is capable of identifying any deviation
from the design center parameters. The design of the AP6020 is con-
servative with respect to the power handling capabilities of the output
devices. The topology guarantees that thermal stress not secondary
breakdown will set the limits of operation, while the computer opti-
mized heat dissipation system insures that excessive thermal stress will
not occur. Yorkville ’s reputation as a manufacturer of reliable equip-
ment will be further enhanced by the AP6020 .
The AP6020 is not only suitable for use in both heavy duty tour-
ing sound reinforcement systems but also when high headroom and
low distortion are needed to fully reproduce the dynamic range and
clarity of today’s CD recordings. It is built to survive grueling road
conditions and constant 2-Ohm operation. Its reliability in a fixed
installation running 4 or 8-ohm studio monitors is without parallel.
Fan Filter Maintenance
The AP6020 is factory equipped with fan filters mounted on the air-
intake grills located on the amplifier’s front panel. Regular cleaning of
these filters will increase the amplifier’s long term reliability. The filters
should be removed and washed at the first sign of visible clogging.
This will typically occur every four to six weeks depending on use and
environment. Replacement filters are inexpensive and can be ordered
CAUTION: The AP6020 can deliver over 2000 Watts of power into a speaker load. Yorkville ’s own high power speaker systems have circuit-breaker
protection built in. Although these speakers will protect themselves, they are unlikely to be damaged by a AP6020 . However, many other speaker manu-
facturers make “high power cabinets” with no protection features at all.
Yorkville Sound is not responsible for any damage which may result as a consequence of exceeding such a speaker’s power handling capability.
Yorkville ’s two year unconditional warranty does not cover any consequential damages to non- Yorkville equipment. Please consider these facts carefully
before you choose to run your AP6020 !