Wilflet Posted March 14, 2011 Share Posted March 14, 2011 when I used to work with a student crew every single physics student would ask this when they started doing sound. I do one wrap for vocals before soundcheck, if they take it off the stand and look like there fumbling make sure it dosnt have a wrap when the set starts. If they take it off fine then do a wrap themselves at the end of the soundcheck then I know iv nothing to worry about. Wrapping the whole way up is never a good idea. Link to comment Share on other sites More sharing options...
Takeiteasy Posted March 14, 2011 Share Posted March 14, 2011 Had a lad with me last week who bloody taped the cable to the stands all the way down.... like every 2inch's !! Link to comment Share on other sites More sharing options...
BlueShift Posted March 14, 2011 Share Posted March 14, 2011 If you are going to do this, do it by placing the mic in the clip, connected, and then wrapping the cable round and hook it over the boom joint knob (technical term?). This way simply unhooking that bit allows the cable to just fall off. Link to comment Share on other sites More sharing options...
RoyJ Posted March 14, 2011 Author Share Posted March 14, 2011 There are a few and then a few too many... and then you get an electromagnet (not going to happen with sound cable) If the line and neutral conductors were in a common casing (as they usually are) they would both be wrapped the same way around any pole. Since the load current then flows in them in opposite directions (relative to the pole) each would generate a field of identical magnitude but opposite polarity to the other, hence no net field. Isn't that the way some circuit breakers work? A short at the load returns current via the protective conductor and the unbalanced currents in the phase conductors then have a net magnetism which is cunningly arranged to throw the trip. It would be the same for audio cable but the fields from milli/micro-volt/amp audio signals would be minuscule. Sorry, but that's absolute bull!a) you're not going to get anywhere near the number of turns from any mains cable to create anything like an electromagnet;b) even if you could you'd need a solid iron core to do soand c) electromagnets are constructed with single core cable, NOT with 3-core TNE cable. You only need one turn to make an electromagnet (see below) and strictly speaking you don't need a core at all, that just concentrates the field that would be created by the geometry of the coil and lets you do useful work with it. You can use any sort of cable carrying any sort of current. Provided the net current flow is non-zero you'll get a field. OT There is a school physics demonstration transformer kit that has a single-turn secondary fashioned out of thick aluminium with a cross-section like rainwater guttering in which you place solder. Firing-up the primary melts the solder from the heat of the multi-amp induced current. We've got one probably from the 1970s but it's ex-PAT and looks pretty lethal so we can't use it. In the dim and distant past of my school days, I've seen the exact thing used as a demonstration.......And yes it was scarry! Thanks all for taking the time to reply,I've learnt a fair bit and been able to reminise about an old physics demo! Thanks again. Link to comment Share on other sites More sharing options...
Rob_Beech Posted March 18, 2011 Share Posted March 18, 2011 .......... boom joint knob......... I'd have had to have TRIED to think of something that silly. I like it! I tend to put a wrap in, only the one though. If it's a singer that doesn't play I'll often use common sense and not bother, but if they play an instrument throughout its unlikely they'll take it off. Generally of that sort of stuff I'd put a wireless out, as I have a few. Rob Link to comment Share on other sites More sharing options...
adamharman Posted March 19, 2011 Share Posted March 19, 2011 Since the load current then flows in them in opposite directions (relative to the pole) each would generate a field of identical magnitude but opposite polarity to the other, hence no net field. Isn't that the way some circuit breakers work? A short at the load returns current via the protective conductor and the unbalanced currents in the phase conductors then have a net magnetism which is cunningly arranged to throw the trip. That's basically how an RCD works. It doesn't matter where the fault current goes, could be through the protective conductor, could be through you, the imbalance will still trip it. And as everybody says, there's no way anything "electrical" could happen from wrapping a cable round a mic stand, especially as it's screened cable. If it's done too tightly and left on there for a long time, it might make the cable a pain to coil though..... Link to comment Share on other sites More sharing options...
paulears Posted March 19, 2011 Share Posted March 19, 2011 What I can't quite work out is why you'd want to do this in the first place? If you want neatness, the clips or lx tape looks the best anyway Link to comment Share on other sites More sharing options...
Andrew C Posted March 19, 2011 Share Posted March 19, 2011 There is a school physics demonstration transformer kit that has a single-turn secondary fashioned out of thick aluminium with a cross-section like rainwater guttering in which you place solder. Firing-up the primary melts the solder from the heat of the multi-amp induced current. We've got one probably from the 1970s but it's ex-PAT and looks pretty lethal so we can't use it. In the dim and distant past of my school days, I've seen the exact thing used as a demonstration.......And yes it was scarry! Thanks all for taking the time to reply,I've learnt a fair bit and been able to reminise about an old physics demo! Thanks again.We have this in use on a regular basis. The solder is in the tray on the left (secondary single turn winding). We also have low voltage output windings, a 6V lamp and a few other indescribable bits! Link to comment Share on other sites More sharing options...
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