Electret lavs, shotguns... +48

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Electret lavs, shotguns... +48

Post by Gizmo1977 »

Had always read, or misunderstood, that electret microphones had no issues if Phantom Power was given.

They had "permanent" charge (which could dissapear) and could be built with little cost, without meaning they where just the crappy ones because brands like DPA do electrets mostly.

Now I'm dealing with cams and broadcast somehow and see many shotgun mics and lavs are built this way and also seen Phantom Power adapters like Audix APS-910.

Questions to confirm or relearn concepts:

- could I put into risk an electret mic when plugging It directly into a mixer with +48 on or should I always use an adaptor like that Audix?
- Same as later question but deciding if enabling +48 whether it's a (shotgun/lav) 416/MKH or ME80/MKE Sennheiser plugged into an XLR input of a TV cam or a minijack on a DSLR.
- Any mic that can be powered with 1 or 2 AAs are surely electrets and "no battery ones" true condensers?

Thanks in advance!!
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Re: Electret lavs, shotguns... +48

Post by Mike Stranks »

Am electret mic is just a form of capacitor mic. Some require 48 V phantom, some require an AA or PP3 battery, some will run on either.

The manual/spec sheet will tell you how to power it.

A twist to this is the facility that some mics have that will run on 'Plug-in' power. These are usually mics with 3.5mm jack plugs that are powered by a 5v (ish) supply provided by the camcorder or portable recorder.

The problems arise if you try and use passive adapters and end up trying to run a 'plug-in' power mic into an XLR input with 48 volt phantom present. That's why might need a specialist converter-adapter so you can run a mic that only needs 5v via a 48 volt phantom supply.

That's the high-level simply version... the experts will be along ere long to flesh that out and correct my mistakes.

In a nutshell: read the manual; never guess or assume!
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Re: Electret lavs, shotguns... +48

Post by James Perrett »

The simplest answer is that if you are unsure then don't use adaptors. If a condenser mic has an XLR output it will require phantom power while, if it has a 3.5mm output, it will require low voltage plug-in power.

If your mic doesn't have the same connector as your device then you will need to use a proper power supply for the mic. There are a few phantom to plug-in power convertors so that you can use a plug-in powered mic with a phantom powered input but to go the other way will almost certainly require an external power supply.

As Mike says - read the manual.
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