Balanced Inputs/Outputs Soundcard
Balanced Inputs/Outputs Soundcard
Author
Discussion

benz0

Original Poster:

344 posts

157 months

Tuesday 5th July 2016
quotequote all
Hi all,

In our meeting room at work we've just been given an XLR input and output for connecting our PC to the conference microphone / PA system, so that we can use it for video conferencing.

I need to get a USB soundcard with compatible inputs and outputs. Can anyone make any recommendations?

Many thanks!

megaphone

11,499 posts

275 months

Tuesday 5th July 2016
quotequote all
You can unbalance a balanced signal, link pin 1 Gnd to pin 3 cold.

Are the XLR inputs mic level or line level? You can overload a mic input if you put line level into it.

You also need to check there is no phantom power on a mic input, this is used to power electret/condenser type mics.

benz0

Original Poster:

344 posts

157 months

Tuesday 5th July 2016
quotequote all
megaphone said:
You can unbalance a balanced signal, link pin 1 Gnd to pin 3 cold.

Are the XLR inputs mic level or line level? You can overload a mic input if you put line level into it.

You also need to check there is no phantom power on a mic input, this is used to power electret/condenser type mics.
Hi megaphone, thanks for your thoughts.


I've no idea if it is mic level or line level, to be honest. I will have to try and find out. Would I just need to look at the mixer to see where it's connected?

For phantom power - again, any tips on how to figure that out? There are power packs under the desk where the mics are installed, but I don't know whether these are just powering the consoles on the desk (it's an interpretation system with 3 channels and headphone outputs).

Thanks!

ben






megaphone

11,499 posts

275 months

Tuesday 5th July 2016
quotequote all
Yes looking at the mixer would usually tell you if it's mic or line. Again the phantom power would likely come from the mixer, although you can get inline phantom power units.

Post up some pics

Mr Pointy

12,896 posts

183 months

Tuesday 5th July 2016
quotequote all
While you can just unbalance the input as described above without knowing the circuitry of the mixer & the computer you can't guarantee that it won't damage something. It very probably won't, but it's not impossible. A couple of these would isolate the connections, although the are stupidly expensive for what they are:

http://www.canford.co.uk/Products/49-363_CANFORD-B...

They do male & female XLR versions. If I can find time I'll look for something cheaper.

The phantom power would be a bigger issue. If you can see the mixer & the input cable goes into a Line input you are ok. If it's a Mic input you may not be - there may also be a switch on that channel that says +48v or Phantom which you can turn off. Maybe post a picture of the mixer & the connections & it may be possible to help further.

benz0

Original Poster:

344 posts

157 months

Tuesday 5th July 2016
quotequote all
Thanks guys, will try and get some pics later!

I think they would have connected it to the line in though.

The idea is that the line out from the laptop goes into the PA system and through the speakers mounted on the walls - and the output from the mic system goes into the laptop.

If they did it as a mic input then there would be a loop in the audio.

Crackie

6,386 posts

266 months

Tuesday 5th July 2016
quotequote all
Sounds like a USB audio interface will do the job for you.

DV247 http://www.dv247.com/search/2974/0/ProductPrice/As... are very likely to have something to suit most budgets. Can't go too far wrong with M-Audio, TEAC, Behringer, Alesis, Focusrite.

They'll all have line in / out, XLR in / out, phantom power and direct USB connections.

Good luck.