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dual audio of radio mic Transmitter

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dual audio of radio mic Transmitter

Postby John Hennessy » Sun Feb 16, 2020 11:54 am

Hi Guys I am looking for advice please I shoot wedding videos and at most hotel they have a radio mic with a single Transmitter jack output I would like to split that to my zoom recorder
what is the best way to do that without upsetting the hotel volume thanks in advance.
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Re: dual audio of radio mic Transmitter

Postby ef37a » Tue Feb 18, 2020 8:37 am

You could probably just use a jack to two jacks 'splitter' cable but if you want to be sure not to load the feed, use a high impedance to mic DI box. A good quality passive one would do but if you wanted the highest possible fidelity there are active boxes. Expect to pay £100+ for a good active DI.

As ever! The make and model numbers of each piece of kit will allow a more precise answer.

I am wrong! https://www.soundonsound.com/reviews/or ... s-di-boxes

^ Stonking vaue!

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Re: dual audio of radio mic Transmitter

Postby ef37a » Tue Feb 18, 2020 10:42 am

Just realized...Surely you want to split the audio output of the RECEIVER?

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Re: dual audio of radio mic Transmitter

Postby Hugh Robjohns » Tue Feb 18, 2020 10:52 am

If it were me, I would purchase an ART DTI box:

Image

https://www.soundonsound.com/reviews/art-dti

...possibly the single most useful device in the whole audio industry! :lol:

This box has two audio channels with the inputs and outputs separated by isolating transformers, and more or less every connector type known to man (or woman).

So... with a bunch of adapter cables to hand, you could unplug the output of the radio mic receiver into the appropriate connector on the input side of the box, and then use one of your handy adapter cables to connect the output of the radio mic into one of the other input-side connectors. That will restore the straight path from radio mic receiver to the venue's PA system.

You then take another cable and connect that to the output side of the box, and run it back to your camera to provide a transformer-isolated split.

The box will take care of any unbalanced/balanced issues, and provide galvanic isolation to avoid ground loops. The fact that it is a low-impedance line level feed from the radio mic receiver means it will be quite happy driving a couple of (relatively) high-impedance destinations without issues.

Note - the output from the DTI box will be the same level that comes out of the receiver... so normally line level, but some might be mic level...

A DTI box is about £50, and you'll need to invest in some appropriate adapters or adapter cables to suit the connections used in the venues you frequent.

H
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Re: dual audio of radio mic Transmitter

Postby ef37a » Tue Feb 18, 2020 12:03 pm

A solution Hugh but I was thinking the OP needs a slave split input and these are almost always found on conventional guitar DI boxes, active or passive.

I had thought of a simple 1:1 transformer isolator but in the absence of any information regarding the receiver we cannot know what another 10k or so will do to the existing level?

Bugger all in all probability but the chap was a bit concerned about this.

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Re: dual audio of radio mic Transmitter

Postby Hugh Robjohns » Tue Feb 18, 2020 12:13 pm

ef37a wrote:A solution Hugh but I was thinking the OP needs a slave split input and these are almost always found on conventional guitar DI boxes, active or passive.

The same facility is available on the DTi box, as all the input sockets are wired in parallel (as are all the output sockets), so you can derive a 'slave split' feed without any trouble... it's just that they'll be on different types of connector -- hence the requirement for some adapters or adapter cables!

Another benefit of the DTI box is that it can handle both balanced and unbalanced sources, whereas a standard DI box will only accept unbalanced sources.

...in the absence of any information regarding the receiver we cannot know what another 10k or so will do to the existing level?

The output impedance of a radio mic receiver is likely to be only 100 Ohms or so, so loading it with a two 10k-ish destinations won't make any practical difference to the level. And even if both destinations are mic inputs with just a couple of K each it still won't affect the level catastrophically!

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