smalljoshua Posted March 2, 2009 Share Posted March 2, 2009 Once again, it seems, I am about to bow to the Blue Room's superior knowledge. I am currently specing sound for a musical, Oliver, I am looking into solutions for Micing a Cello. I have decided to use a Lav Mic on the instrument. The problem I have come across is getting the signal from the Mic into the desk. The Lav Mic I have is MP33751 from CPC. I need to run this into a multcore and into a Behringer SX2442FX mixing desk. I have thought about using a Radio Mic set to avoid having to buy/make something but I don't have the budget to do this. I also need something which can run off of Phantom Power so I don't have to worry about batteries. My question is, are there any units/schematics that will allow me to use this Mic into a mixer? Josh Link to comment Share on other sites More sharing options...
Simon Lewis Posted March 2, 2009 Share Posted March 2, 2009 Josh, There are some good tips and circuits for powering / biasing electret capsules on this website. HTH, Simon Link to comment Share on other sites More sharing options...
J Pearce Posted March 2, 2009 Share Posted March 2, 2009 You'll want a power supply, for which a 9V battery will do, then a dc blocking capacitor, then something to balance the signal before it hits your multicore. So 9V battery across the two terminals (check which way round!), then a dc blocking capacitor in series with whichever side has the positive side of the battery, all plugged into a DI box that can be set to have 0dB attenuation. Should be able to build the circuitry into a XLR plug, with a 9v battery tail thing hanging out of the top. [edit]Simons link is more comprehensive than my fag packet design. Also with a bit of thought you could use a voltage regulator to get the 9V from 48V phantom. Link to comment Share on other sites More sharing options...
bruce Posted March 2, 2009 Share Posted March 2, 2009 Hmm... I've got a unit, supplied by http://www.orchid-electronics.co.uk/ (mixermend on this forum), which is designed to drive similar mics from a phantom supply. I wonder if it would do the job...I don't see why not... check out the "contact microphone system" on their website. Link to comment Share on other sites More sharing options...
p.k.roberts Posted March 2, 2009 Share Posted March 2, 2009 If you fancy a bit of DIY then register on this site and have a look in the Library (very useful site to register with anyway!); http://www.microphone-data.com If you need a bargain solution, then try CPC part number MP33119, or if the budget will stretch a bit, then there's a shed load on this Canford page; http://www.canford.co.uk/Browse/20986.aspx Link to comment Share on other sites More sharing options...
smalljoshua Posted March 2, 2009 Author Share Posted March 2, 2009 Thanks for all of the replies. I will look over all of them in the next couple of hours and get back to you. Thanks again. Josh A concurrent post has been automatically merged from this point on. If I were to use the circuit diagram that Simon linked to, thanks Simon, and this DI DP29609 would I then be able to take the phantom power from the Balanced side of the transformer and use it for the power supply on the unbalanced side? How would I tap the phantom power from the Balanced line? I know I would use a Voltage Reg into the +ve of the circuit and feed that from the Phantom. I think that I would wire the GND on the circuit direct into Pin 1 on the XLR and the Output from the circuit into the DI box. Am I close? I know this sounds basic but I don't want to blow anything up. Thanks for all of the help. Josh Link to comment Share on other sites More sharing options...
smalljoshua Posted March 3, 2009 Author Share Posted March 3, 2009 Anyone? I have done a quick test circuit with the schematic simon mentioned, it works. I could build it into a Jack plug and be done with it by putting it through a DI but I'd rather have an all in one solution. Josh Link to comment Share on other sites More sharing options...
Sound Man Posted March 3, 2009 Share Posted March 3, 2009 This project should solve all of your problems. A PCB is available for this circuit. David Link to comment Share on other sites More sharing options...
smalljoshua Posted March 4, 2009 Author Share Posted March 4, 2009 I take it you mean this circuit? http://www.sound.westhost.com/p93-f6.gif If this is the case, then that looks very easy and quick to build into a metal box. Thanks Josh Link to comment Share on other sites More sharing options...
Sound Man Posted March 4, 2009 Share Posted March 4, 2009 Yes that's the one. I would suggest getting a PCB if you are able to as that will make it easier to build the circuit. Also the housing he has available would be worth looking into as you could fit a socket for the mic input at the opposite end to the XLR connector making a very slim line unit. If you have a time issue, I believe this product from CPC would be a suitable alternative. Datasheet available from here. David Link to comment Share on other sites More sharing options...
smalljoshua Posted March 4, 2009 Author Share Posted March 4, 2009 Thanks for the confirmation. Time isn't an issue, neither is making the PCB. I can make it for free in school. Looks like I'll be making this one then. Thanks Josh Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.