Reverse Di Box

[addoaddo]

I am currently using a 24 channel analogue Yamaha mixing desk. This has 16 balanced microphone inputs and 8 mono unbalanced inputs (paired up in stereo) .

 

On a few occasions I have used up all 16 microphone balanced inputs but need more channels. I would like to use the extra 8 channels but as these are only mono inputs I am not sure what is the best way to connect them.?

 

For example the oblivious instrument to move is the keyboards on stage is connected via two DI boxes which produces a balanced line signal through a 30m multi-core to the desk. If I just take the hot signal it removes the benefit of the balanced line.

 

I did think that I could feed the input in to a compressor / limiter and then take the mono output to the desk but this is an overkill.

 

What I need is a piece of equipment that takes a balanced line in and outputs an unbalanced output at a reasonable cost as I may need 8 of these

[Paul TC]

I have used these in the past to go from balanced to unbalanced connections, have need XLR to jack cables as well, either of these boxes as a get of jail unit, Behringer HD400 or ART Cleanbox Or this might be suitable to do what you want for more channels, ART T8 8-Channel Transformer/Isolator

[boatman]

You need a box containing a 1:1 transformer with enough overhead to cope with line level signals. I've got a couple of Neutrik boxes from CPC.

 

There are two cheaper DBBLOX adaptors also available from CPC:- AV17470 & AV17472; but I've never used these so can't recommend them.

[paulears]

The real problem here is simply the transfer from stage to mixer, isn't it. We have some unbalanced sources, connected to unbalanced inputs that are working at the right levels - so we have a choice of transformer balancing them at the stage end, and then unbalancing at the mixer end - costing quite a few quid for the conversion boxes, or simply trying it with unbalanced, using just 1&3, or 1&2 and some adaptors. From history, sometimes it works perfectly, sometimes not. The successful times had one thing in common. The keyboards were driven from wall wart power supplies with no earth connection. The unsuccessful times, where I got hums and buzzes were when the keyboards had IEC mains inputs. Buying 16 devices to let you plug in keyboards can be very expensive - so if you know what the keyboards are - it's well worth trying it before spending the dosh!

[revbobuk]

It's worth just being completely sure (I'm sure you have checked this) that the 'Jack' inputs on the Yam desk are in fact unbalanced. Many mixers use balanced TRS for this function, and it's not always obvious.

[Bobbsy]

Revbob beat me to it. Every Yamaha analogue desk I've used had balanced line level inputs on TRS. Some, from memory, claimed in the manual that they could also accept unbalanced on TS.

 

Worth checking the manual for the model of mixer you have...Yamaha are very good about keeping manuals online if you don't have the printed copy.

 

Bob

[addoaddo]

Thanks for the inputs. The mixer is an MG24/14FX and the manual does state that the channels 17 - 24 are un-balanced inputs. The ART devices look the way to go but I will have to add batteries to the DI boxes as the phantom power will not go through these devices.

[boswell]

Ch17-24 are unbal line inputs, you do not have phantom on these channels

[chelgrian]

I am currently using a 24 channel analogue Yamaha mixing desk. This has 16 balanced microphone inputs and 8 mono unbalanced inputs (paired up in stereo) .

 

You can buy 8 channel de-balancing devices for example

 

http://www.arx.com.au/International/de-balance8.htm

 

of course you can only feed that with something near line level it won't cope with mics so if you wanted more mic inputs you'd need to put an 8 channel mic pre in front of it.