Best way to mix/pre-amp four lavalier mics (and how to duplicate the mic's output pre-mixer)?

[sep]

Based on my small amount of research I'd need to convert the 3.5mm input to XLR.

This converter scales phantom power down to plug-in power:

This one doesn't convert phantom power and is less expensive. Apparently, using this adapter with phantom power on is dangerous so it'd have to be turned off. It's unclear to me whether, with phantom power turned off, the mixer would still apply enough pre-amplification.

For a mixer I'm looking at this one. Happy to hear recommendations for more suitable or less expensive mixers.

Also, I'd like to duplicate the lavalier mic's signal before getting to the mixer. Ie., send one copy of the signal to the mixer and another to an iPhone (via an audio-jack adapter). Will this work?

 

[No. 5]

Based on my small amount of research I'd need to convert the 3.5mm input to XLR.

This converter scales phantom power down to plug-in power:

This one doesn't convert phantom power and is less expensive. Apparently, using this adapter with phantom power on is dangerous so it'd have to be turned off. It's unclear to me whether, with phantom power turned off, the mixer would still apply enough pre-amplification.

As I understand the workings of a plug-in power microphone, your lavaliers will need 3V to 5V of bias voltage to function (that's what the first adaptor is providing by stepping down a 48V phantom power input). Without it you won't get any sound, so no sound with the second option unfortunately. Injecting the needed low voltage into the signal path to power the microphone only takes a simple circuit and only a couple dollars in parts if you're handy with a soldering iron.

For a mixer I'm looking at this one. Happy to hear recommendations for more suitable or less expensive mixers.

Also, I'd like to duplicate the lavalier mic's signal before getting to the mixer. Ie., send one copy of the signal to the mixer and another to an iPhone (via an audio-jack adapter). Will this work?

Personally, I would use the FX send on that mixer as the "splitter" to go to the iPhone, then you'll be able to mix and level your four lavalier channels independently of your main output so you can get the best sound going to the iPhone. Another option would be to send the Control Room or Headphone out to the iPhone. That would be a little easier than having to do two separate mixes, but you'd still get the advantage of a separate level control going to the iPhone.

 

[sep]

As I understand the workings of a plug-in power microphone, your lavaliers will need 3V to 5V of bias voltage to function (that's what the first adaptor is providing by stepping down a 48V phantom power input). Without it you won't get any sound, so no sound with the second option unfortunately. Injecting the needed low voltage into the signal path to power the microphone only takes a simple circuit and only a couple dollars in parts if you're handy with a soldering iron.

Personally, I would use the FX send on that mixer as the "splitter" to go to the iPhone, then you'll be able to mix and level your four lavalier channels independently of your main output so you can get the best sound going to the iPhone. Another option would be to send the Control Room or Headphone out to the iPhone. That would be a little easier than having to do two separate mixes, but you'd still get the advantage of a separate level control going to the iPhone.

Thank you! I wonder what the use case for the regular VXLR without power is?

Your idea about the mixer sounds good, except that we wanted to split the audio of *each* iPhone, not just their mixed output. But we might end up not doing this after all...

 

[No. 5]

Thank you! I wonder what the use case for the regular VXLR without power is?

Certainly! It's likely for a line level signal rather than a microphone signal.

Your idea about the mixer sounds good, except that we wanted to split the audio of *each* iPhone, not just their mixed output. But we might end up not doing this after all...

I see. Is the intent to have the audio from each microphone recorded in its own track in addition to having all of the mics mixed together?

 

[Rja4000]

I'm not sure I understand what you try to do.
If I had to send 4 mics with phantom to 2 different destinations, I'd do it after AD today (using a 4 mics interface or mixer).

Now, in the old days of analog, we used to use transformer based splitters, that were made for that purpose (and quite expensive).
Nowadays, in the very unlikely situation I'd had to split signal before AD, I'd probably use something like this:

Catapult - Radial Engineering

The Catapult is a passive audio snake that allows you to send four channels of analog audio over standard Cat 5 or Cat 6 Ethernet cable.

www.radialeng.com