YORKVILLE ap4020 ys4020, Owner'S Manual

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CLIP LEDS
The CLIP LEDS on the front panel will visibly indicate any sig-
nal excursion beyond the dynamic headroom of the amplifier.
RELIABILITY
The AP4020/4040 is designed and manufactured by
Yorkville Sound. Each unit undergoes a thorough, temperature
cycled burn-in period, and each circuit is tested by both man-
ual and sophisticated computer controlled equipment which is
capable of identifying any deviation from the design center
parameters. The design of the AP4020/4040 is conservative
with respect to the power handling capabilities of the output
devices. The topology guarantees that thermal stress not sec-
ondary breakdown will set the limits of operation, while the
computer optimized heat dissipation system insures that
excessive thermal stress will not occur. Yorkville’s reputation
as a manufacturer of reliable equipment will be further
enhanced by the AP4020/4040.
The AP4020/4040 is not only suitable for use in both heavy
duty touring sound reinforcement systems but also when
high headroom and low distortion are needed to fully repro-
duce the dynamic range and clarity of today’s CD record-
ings. It is built to survive grueling road conditions and con-
stant 2 Ohm (4 Ohm in the AP4040) operation. Its reliability
in a fixed installation running 4 or 8-Ohm studio monitors is
without parallel.
OUTPUT CONNECTIONS
WARNING: When driven to full power in Bridge Mode. There is more
than 100Vrms appearing between the binding posts. This represents
a significant shock hazard and due care should be taken when mak-
ing any speaker connections. Ensure that no strands of bare con-
ductor are exposed after inserting the speaker wire into the hole in
the side of the binding post terminals.
The AP4020/4040 has 5–way binding posts and Neutrik
four contact Speakon™ connectors for output speaker connec-
tions. Connection to the binding posts can either be made
with a banana plug inserted into the end of the post.
There are two Speakon™ connectors. The Speakons™ are
connected to the amplifier’s outputs whether the amplifier is
in stereo, mono, or bridge modes. Each Speakon™ output
connector (output A and output B) is wired in parallel with it’s
respective binding posts for two channel two cable connec-
tions (figure 1).
Speakon™ output A also doubles as the A&B/Bridge connec-
tor. This Speakon™ contains both channels on one connector.
This is convenient when connecting one speaker to the ampli-
fier in bridge mode where the speaker is connected across the
positives of each amplifier output. Configure the mode switch
for bridge and connect the speaker to pins +1 and +2 of the
bridge/bi-amp Speakon (figure 3).
To connect a bi-amp speaker, configure the amplifier for
stereo and connect to the bridge/bi-amp connector but use all
four terminals in the Speakon connector which will connect A
and B outputs separately to the speaker (figure 2). Connection
configurations are labeled on the back panel.
AP4020 AP4040
Both Channels Driven
Load 1KHz 1KHz 1KHz 1KHz
(Ohms) Cont. Avg. Burst Cont. Avg. Burst
2-Ohm Mode 2-Ohm Mode 4-Ohm Mode 4-Ohm Mode
8 475 625 750 1200
4 750 1200 1200 2175
2 1200 2175 n/a n/a
Bridge Mode
Load 1KHz 1KHz 1KHz 1KHz
(Ohms) Cont. Avg. Burst Cont. Avg. Burst
2-Ohm Mode 2-Ohm Mode 4-Ohm Mode 4-Ohm Mode
8 1500 2400 2400 4350
4 2400 4350 n/a n/a
2 n/a n/a n/a n/a
POWER OUTPUT
All values are in WATTS. Measurements were made at the 0.1% distortion point. Some CONTINUOUS AVER-
AGE POWER measurements required line currents greater than 15 Amps. The amplifier under test was plugged
into an IDEAL POWER LINE consisting of a REGULATED 120 VAC RMS 60 Hz pure sine wave. Ordinary AC
“wall outlet” lines will always exhibit varying and unpredictable amounts of sag. To produce objectively verifiable
and accurate specifications these unknown factors must be eliminated by using an ideal AC line. When using an
ordinary electrical outlet, it will usually be possible to get 2400 Watts when the
AP4020 is bridged into 4-ohms
( AP4040
bridges at 8-Ohms).
The BURST measurements use a 10mS burst at 1KHz with a 1/8 second pause
between bursts. The 1KHz burst represents the maximum possible sine wave output power.