Damon999 Posted June 22, 2011 Share Posted June 22, 2011 Hello, I'm trying to make use of these mics which I have borrowed off another company on the proviso that I fit XLR's, but I have tried to wire them up and although they pick up a signal, there is a lot of noise (this is not down to dodgy soldering before anyone goes there :-) ) http://dl.dropbox.com/u/12679239/photo.JPG I am told they are Audio Technica (all be it quite an old model) but does anyone recognise them and know of the model number. The lead has 4 insulated cores and shield (I assume it's star quad - two red cores and two white). The strange thing is that when tested on a Soundcraft Notepad, if I turn off phantom power, the mic begins to work perfectly for a few seconds while the circuit discharges - almost as if they need a lower voltage phantom power or something. I have tried another desk as well, as the Notepads don't have the quietest preamps. If anyone has any answers, it would be much appreciated. Cheers, Damon Link to comment Share on other sites More sharing options...
revbobuk Posted June 22, 2011 Share Posted June 22, 2011 It's hard to get a sense of scale from the picture, but these could be lavalier mics - the lower section looks as if it is made for a clip - in which case they would be looking for something like 3v instead of 48. How big are they? Link to comment Share on other sites More sharing options...
Simon Lewis Posted June 22, 2011 Share Posted June 22, 2011 Most lapel mics need a bias voltage, not phantom power... Link to comment Share on other sites More sharing options...
T.Colwill Posted June 23, 2011 Share Posted June 23, 2011 I'm afraid I don't know what mic's these are, but top left of the picture, is that not a mouse for a Mac? That might give an idea of scale for those who might know. Tim Link to comment Share on other sites More sharing options...
Damon999 Posted June 23, 2011 Author Share Posted June 23, 2011 Thanks for the replies. I have been told they are Audio Technica hangers but don't know the model number. They are definately not lavs as they are too big although it is hard to get an idea of size from the picture. It seems odd that they would have anything other than normal phantom. I tried doing a bit of research and found a thing called T power which I hadn't come across before. Due to their age, is it very likey that this may be how they're powered? Cheers, Damon Link to comment Share on other sites More sharing options...
Brian Posted June 23, 2011 Share Posted June 23, 2011 ...is it very likey that this may be how they're powered?Probably not. Mics for specialist applications, especially those for permanent installs, often have odd powering requirements. From your description it really does sound as though 48v phantom is just too high a voltage. Link to comment Share on other sites More sharing options...
BOD20 Posted June 23, 2011 Share Posted June 23, 2011 If they are Audio Technica hanging mics, then their current range uses a remote power module like this - http://cgi.ebay.com/Audio-Technica-AT8536-11-52-remote-power-module-/260510304692 The mic is permanently wired into one end of the power module, with a smaller (less obtrusive) diameter cable, and the power module terminates with an XLR connector for connection to the desk with a normal mic cable. I guess they wouldn't work without that power module. Link to comment Share on other sites More sharing options...
Damon999 Posted June 23, 2011 Author Share Posted June 23, 2011 Little update. We have borrowed an external phantom power unit to try on these mics and with them going through it, but with the unit turned off and the desk power on, the issue is resolved. It does seem to me that they just don't like the level of phantom power but I don't see why. Link to comment Share on other sites More sharing options...
Brian Posted June 23, 2011 Share Posted June 23, 2011 It does seem to me that they just don't like the level of phantom power but I don't see why.Errr, because they weren't designed for 48v phantom power? Phantom powering is a general technique, the 48v sort is but one version. 12v phantom powering is just as valid. Link to comment Share on other sites More sharing options...
Damon999 Posted June 23, 2011 Author Share Posted June 23, 2011 Well I've never encountered anything that uses 12v phantom power so I assume it's not all that common these days, but it does sound like that is probably the case here. Just out of interest, is 12v phantom still used on any of today's products? Link to comment Share on other sites More sharing options...
Sound Man Posted June 23, 2011 Share Posted June 23, 2011 Have you tried e-mailing Audio Technica to see what they say. David EditJust after a few clicks on the above site I've found this webpage. If this is so, then you need a power module for each of your mics. Link to comment Share on other sites More sharing options...
Damon999 Posted June 23, 2011 Author Share Posted June 23, 2011 Aha. Now that does seem to make more sense as the White cores are more of an off White/yellow colour so it seems this would be the case. Cheers Link to comment Share on other sites More sharing options...
paulears Posted June 23, 2011 Share Posted June 23, 2011 If you look at many specs for microphones, you'll see the phantom power specified as 9-52V DC - so although 48V is often considered the 'norm' - many items of kit, especially battery powered ones might only do maybe 18V - as it was simple to get from a couple of 9V batteries. Link to comment Share on other sites More sharing options...
Damon999 Posted June 23, 2011 Author Share Posted June 23, 2011 Just found this following a search: http://www.diyaudio.com/forums/musical-instruments/101000-wiring-some-hanging-mics-print.html Which confirms what the power module actually does and that they do indeed operate on reduced power (5v). Thanks for all the replies. Damon Link to comment Share on other sites More sharing options...
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