Tannoy I9 user manual Pin 1+ is Positive Pin 1- is Negative, b

5.1 Connectors and Cabling for Distributed Line Operation

Connections are identical to those used in low impedance mode, via the4-pole Neutrik Speakon connectors (see section 4.1):

Pin 1+ is Positive

Pin 1- is Negative

Distributed line systems are much more efficient in power transfer and do not require as large cables as in low impedance mode. This can create significant savings in cable costs. Refer to the following table for guidance in cable length versus power loss. A power loss of 11% amounts to a loss of 0.5db, and 50% to a loss of 3dB.

CABLE	C.S.A. OF	AWG	CABLE	% POWER	% POWER	% POWER	% POWER
RUN (m)	EACH		RESISTAN	LOSS	LOSS	LOSS	LOSS
	CONDUCTO		CE Ω	INTO	INTO	INTO	INTO
	R (mm)			70V 60W	70V 30W	70V 15W	70V 7.5W
				100V N/C	100V 60W	100V 30W	100V 15W
100	1	17	3.3	4.8	2.4	1.2	0.6
	1.5	15	2.1	3.1	1.5	0.8	0.4
	2.5	13	1.3	2.0	1.0	0.5	0.2
500	1	17	16.6	20.3	11.1	5.9	3.0
	1.5	15	10.4	13.7	7.2	3.8	1.9
	2.5	13	6.6	9.1	4.7	2.4	1.2
1000	1	17	33.2	33.7	19.9	11.1	5.9
	1.5	15	20.8	24.1	13.5	7.2	3.8
	2.5	13	13.1	16.7	9.0	4.7	2.4
5000	1	17	166	71.8	55.5	38.4	23.7
	1.5	15	104	61.4	43.8	28.1	16.3
	2.5	13	65.7	50.1	33.0	19.8	11.0

Distributed line operation is a good choice when so many speakers are used that the impedance would be too low to run from a low impedance amplifier

For distributed line (70.7/100V) operation, the rotary switch can be adjusted to select the wattage required. The table below shows the rotary positions (moving clockwise) for 70.7 and 100V operation.

Position	70.7V line	100V line
(Clockwise)	Watts	Watts
A	7.5	15
B	15	30
C	30	60
D	60	N/C

Figure 5b demonstrated the method of connecting the speakers to a distributed line amplifier.

Figure 5b

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