Klark Teknik DY11 7HJ manual More about splitters, Isolated splitter, Square ONE Splitter

More about splitters

Isolated splitter

An isolated splitter typically uses a 1:1:1:1 ratio transformer to achieve the audio isolation. The mic input signal is connected to the primary winding of the transformer, with all of the split points derived from the secondary windings. Additional ‘ground lift’ switches may be added to each of the split points providing the option to fully isolate individual parts of the system, if required.

PA company responsibility

Sensitive audio signals

	-40dB (0.01V)
	-40dB (0.01V)
Outside
Broadcast	Local
	Ground

ISOLATED

Stage box (isolated)

-40dB (0.01V)

-40dB (0.01V)

		MON console
	Local	(for example, the
		Midas Siena)
Ground

Independent broadcaster

Grounds

			FOH console
	Local	(for example, the
Ground			Midas Verona)

Isolated systems are the next step up from a passive system and offer a big increase in performance, although this comes at a price. To get the best out of an isolated system a very high quality transformer is required, which is expensive.

Although the isolated splitter addresses one of the fundamental problems inherent in passive systems by providing isolation, it doesn’t solve the problem of sensitive low level mic signals being carried over long distances and their susceptibility to picking up additional noise from other sources, which is ultimately amplified at the mixing console. When using a 1:1:1:1 ratio transformer the loading on the mic and the extra capacitance remains, resulting in high frequency loss. Also, the input impedance of each console added to the system will reduce the overall level. There are 3:1:1:1 ratio ‘step down’ transformers available that compensate for the high frequency loss by lowering the gain.

Phantom power (+48V) will also need to be provided for the mics, which may entail connecting one of the consoles in a passive parallel splitter-type configuration or adding a separate supply.

Square ONE Splitter 25