Yorkville Sound AP1020 manual Power Output, Clip LEDs, Reliability, Output Connections

Clip LEDs

The Clip LEDs on the front panel will visibly indicate any signal excursion beyond the dynamic headroom of the amplifier.

Reliability

The AP1020 is designed 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 equip- ment, which is capable of identifying any deviation from the design parameters. The design of the AP1020 is conservative, 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-optimized heat dissipation system insures that excessive thermal stress will not occur.

The AP1020 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 reproduce the dynamic range and clar- ity of today’s CD recordings. The AP1020 is built to survive grueling road conditions and constant 2-ohm operation. Its reliability is a fixed installation running 4 or 8-ohm studio monitors is without parallel.

Output Connections

The AP1020 has 5-way binding posts and Neutrik four con- tact Speakon™ connectors for output speaker connections. 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 con- nected 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 its respective binding posts for two channel two cable connections (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 amplifier in bridge mode where the speaker is connected across the posi- tives of each amplifier output. Configure the Mode switch for Bridge and connect the speaker to pins +1 and +2 of the bridge/ biamp Speakon™ (figure 3).

To connect a biamp speaker, configure the amplifier for Stereo and connect to the bridge/biamp connector but use all four ter- minals in the Speakon™ connector which will connect A and B Outputs separately to the speaker (figure 2). Connection configu- rations are labeled on the back panel.

Impedance Mode Switch

The AP1020 comes factory-configured to deliver its maximum power into a 2-ohm load. However, it is possible to switch your AP1020 to deliver its maximum power into 4-ohms. The switch is located on the rear panel above the line cord. To prevent damage to the amplifier’s circuitry, only switch modes when the amplifi- er’s power switch is off. This feature is meant to be used when the speaker load is known. Please Note: In the 4-ohm configuration, the minimum load per channel is 4-ohms. The minimum Bridge load is 8-ohms. Attempting to operate into 2-ohm loads while in the 4-ohm configuration will cause the amplifier to go into current limit, thermal limit or both.

The Power specification chart in this manual shows the powers that can be obtained for various configurations and loads.

Power Output

One Channel Driven

Load	1 kHz Cont.	1 kHz Burst	1 kHz Cont.	1 kHz Burst
(ohms)	Average		Average
	2-ohm Mode	2-ohm Mode	4-ohm Mode	4-ohm Mode
8	180	200	280	310
4	310	380	500	590
2	520	650	n/a	n/a
Both Channels Driven
Load	1 kHz Cont.	1 kHz Burst	1 kHz Cont.	1 kHz Burst
(ohms)	Average		Average
	2-ohm Mode	2-ohm Mode	4-ohm Mode	4-ohm Mode
8	165	250	250	290
4	270	350	400	560
2	400	600	n/a	n/a
Bridge Mode
Load	1 kHz Cont.	1 kHz Burst	1 kHz Cont.	1 kHz Burst
(ohms)	Average		Average
	2-ohm Mode	2-ohm Mode	4-ohm Mode	4-ohm Mode
8	550	700	840	1100
4	840	1200	n/a	n/a
2	n/a		n/a	n/a

All values are in Watts. Measurements were made at the 0.1% distortion point. Some continuous average 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-outletlines 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 800 Watts when the AP1020 is bridged into 4-ohms. The burst measurement uses a 10 ms burst at 1 kHz with a pause of 1/8 second between bursts. The 1 kHz burst represents the maximum possible sine wave output power.