Ashly TRA-4150 manual REAR PANEL FEATURES 7.1Input Connectors

Operating Manual - Powerflex Multi-Channel Power Amplifier

* Powerflex 6250 shown - Powerflex 4400 only has channels 1-4.

7.REAR PANEL FEATURES

7.1Input Connectors

The Powerflex inputs use 1/4" tip-ring-sleeve (TRS) phone jacks, balanced XLR jacks, and balanced two piece "Euroblock" style connectors. The three types of connectors are wired in parallel and may be used balanced or unbal- anced. Use the euro-block connectors to daisy-chain multiple amps together . Input XLR jacks are pin 2 hot (+), meaning that a positive voltage applied to pin 2 will result in a positive output voltage across the speaker terminals. Pin 2 of the XLR jack is equivalent to the tip of the 1/4" TRS jack.

Balanced Inputs

It is recommended that balanced input connections be used whenever possible to take full advantage of the amplifier's common mode rejection properties, and to reduce ground-loop problems. The (+) signal is on pin 2 of the XLR, and the tip of the phone jack. The (-) signal is on pin 3 of the XLR, and the ring of the phone jack. If a hum problem per- sists, try connecting a balanced signal to the Euroblock input with the input cable's shield lifted at the amplifier end of the cable (ie. no ground connection), but connected to ground at the signal source. This eliminates potential ground currents through the input cable yet preserves the benefits of shield- ing.

Unbalanced Inputs

If an unbalanced XLR input connection is used, pin 3 should be connected to input ground (pin 1). If the 1/4" input jack is used unbalanced, the use of a mono (tip-sleeve) plug

	Tip (+)
	Ring (-)
	Sleeve (Ground)
			Stereo Phone Plug
			Balanced Connection
2=(+)				XLR Male
3=(-)				Balanced
1=(gnd)				Connection
- +		+ -
			Euroblock
			Input Connector

Ground

Balanced Audio Connections

Tip (+)

Sleeve (Ground)

Mono Phone Plug

Unbalanced Connection

will automatically tie the (-) connection to input ground. Note: Never float the (+) or (-) input connection when using an un- balanced source. If connecting an unbalanced signal to the Euroblock input, connect the signal to (+) and the cable shield to both (-) and ground.

2=(+)

3=(gnd)

1=(gnd)

Signal (+) - +		+ -
(-) Input
Tied To
Ground	Ground

XLR Male

Unbalanced

Connection

Euroblock

Input Connector

Unbalanced Audio Connections

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