Yorkville Sound AP2020 manual Output Connections, Impedance Mode Switch, Power Output

ONLY switch modes when the amplifier’s power switch is OFF!

This feature is intended to be used where the load is known.

PLEASE NOTE: In the 4-ohm configuration, the minimum load per channel is 4-ohms and the minimum BRIDGE load is 8–ohms. Attempting to operate into 2-ohm loads while in the 4-ohms 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 achieved for various configurations and loads.

2-ohm4-ohm

MODE SWITCH

The AP2020 is not only suitable for use in both heavy duty touring sound reinforcement systems but also when high head- room 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 opera- tion. 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 here is more than 70 Vrms appearing between the binding posts. This represents a significant shock hazard and due care should be taken when making any speaker connections. Ensure that no strands of bare conductor are exposed after inserting the speaker wire into the hole in the side of the binding post terminals.

The AP2020 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 forked lug on the post’s neck or banana plug inserted into the end of the post.

There are three Speakon™ connectors, one for each channel output and a third for bridge/bi-amp connections. All three connectors are connected to the amplifier’s outputs whether the amplifier is in stereo mono or bridge modes. Connection configurations are labeled on the back panel. Each Speakon™ output connector (output A, output B) is wired in parallel with it’s respective binding posts for two channel two cable con- nections (figure 1).

The Bridge/Bi–amp connector 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 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).

Impedance Mode Switch

The AP2020 comes factory configured to deliver it’s maxi- mum power into a 2-ohm load. However, it is possible to switch your AP2020 to deliver it’s maximum power into 4- ohms. The switch is located on the rear panel above the line cord. 2-ohm mode is selected if the switch is in the LEFT posi- tion, 4-ohm mode is selected if the switch if the switch is in the right position. To prevent damage to the amplifier’s circuitry

Power Output

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 outlet” lines will always exhibit varying and unpredictable amounts of sag. To produce objectively verifiable and accurate specifi- cations 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 AP2020 is bridged into 4 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.

One Channel 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	330	350	425	475
4	550	650	725	870
2	850	1050	n/a	n/a
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	250	350	400	450
4	460	650	615	800
2	650	1050	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	950	1200	1250	1600
4	1300	2100	n/a	n/a
2	n/a	n/a	n/a	n/a