Hafler SR2800CE, SR2300CE owner manual Floated Equipment, Level Controls

FLOATED EQUIPMENT

Units with a 2-pin mains power cord have no means to connect the audio output ground to earth ground, so usually the audio output ground is floated from earth ground. However, this does not insure that when installed in a system, the audio output ground will remain floated from earth ground. The input cable to this equipment may already be connected to earth ground earlier in the audio chain, and it will typically be carried straight through to the output. It is also possible that the audio output ground connects to the earth ground through the chassis to an earth-grounded rack. The only way to know for sure is to test the installed system. Use an ohmmeter to check for continuity between the earth ground socket of the mains power receptacle and the audio output ground. If the audio output ground is not connected to earth ground, it is floated

equipment.

Consult the following diagrams for examples of recommended wiring techniques:

FLOATED,		XLR, 1/4" TRS Amplifier
	SHIELDED TWISTED PAIR	2
BALANCED
		3
SOURCE
		1
	shield connected at both ends	Shield
FLOATED,		XLR, 1/4" TRS Amplifier
	SHIELDED TWISTED PAIR	2
UNBALANCED
		3

SOURCE

1

Audio

Ground

Chassis

Audio

Ground

FLOATED, UNBALANCED SOURCE

shield connected at both ends		Shield
		XLR, 1/4" Mono Amplifier
COAX OR TWISTED PAIR			2
			3
		Shield	1
		1/4" Mono: sleeve shorts
		— input to Audio Ground;
	XLR: short pins 1 & 3 together

Chassis

Audio

Ground

Chassis

The output XLR jack accepts a female XLR plug and provides a hard-wired pass-through of all 3 pins of the input jack.

LEVEL CONTROLS

The gain for each channel can be controlled individually using the front panel level control. The controls have 32 detented positions that are calibrated in dB. The maximum gain position is marked as the "0 dB" position, and the lower gain posi- tions indicate the amount of attenuation relative to the maximum gain position in dB. Minimum gain position is marked as “Off” and represents over 100dB of attenuation relative to the maximum gain position.

The CH B level control is used for all Bridged Mono configurations, and 100V and 70V modes (Except for SR2800 Dual 70V mode).

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