Whats A 70v Network? N How Does It Work?

[tacomabanga1986]

i was lookin into some in wall speakers and outdoor speakers from partsexpress.com and seen some say, diff watts n then 70v setup, how does this work and what is needed for it to work? i was just wondering cause i like to learn some new things, n when we went to the beach they was a put put place that had jbl mids/highs with tic subs n it sounded awesome outside, it was the best outdoor speaker system ive ever heard, n sounded so rich n clean, n that Jamaican music they was playin had some lows in it to, i couldn't find those jbls anywere, not even on jbls site, but i seen tics in partsexpress n they look pritty cool

so does anyone kno what a 70v audio network is?

[qu1cks1lver56]

70 volt systems are for like restaurants and stores where they have a shit load of speakers to run off the same amp.

[tacomabanga1986]

i was thinkin that but ied like to kno how it works, or how it can go that low of ohms n what knot

[MickyMcD]

The 70 or 100 volt 'constant' level is a myth. It is not a constant voltage level with adjustable amplitude or anything of the sort. What an installation 70V or 100V system is doing is using a step-up transformer (some amplifiers, like Crown Com-Tech's, DC's, etc etc need no transformer) to maximise the voltage output over current. A higher voltage transmission means that you can get the same amount of power a further distance on less copper. Each speaker then has a step-down transfomer to bring the voltage back down to a safe and usable level to drive said louspeaker.

The transfomers have a coil tap, in which the ouput windings can be selected giving an often wide choice of power output and resistance. A high voltage audio circuit often has resistance not measured in the usual multiples of two, as each loudspeaker is configured individually for power input using the coil taps.

DO NOT run a 70v system from a standard amplifier. Chances are your amplifier will let out the magic smoke, and once you let the smoke out it is very hard to get it to go back in. Likewise, do not run standard impedance loudspeakers on a 70v network too loud. They may not like the extra high voltage. Some will take it, some won't.

Cheers,

Mick