Mixer (BAL / XLR) Output to BOSE L1 (UNBALANCED / TS) Input

[MoonMix]

hello...

have a gig on friday whereby I will be using my Mackie ONYX 1640i board > via XLR snake to stage > BOSE L1 (Model 1) 1/4" Unbalanced Input.

I have XLR to TS cables (Hosa)...from the snake's Outs to the BOSE heads...but was wondering:

1) What exactly happens inside that adapter cable...??? For Stereo XLR Outputs (L & R)...two pins (1 & 3) are hot (+ & -) & one pin (2) is earth, correct...??? So...going to the 1/4" TS side (where pin 1 is hot & pin 2 is earth ?)...what happens to pin 3...??? Is it shunted to ground, tied to 1, or left open...???

2) Is this my correct connection between these two devices (XLR > TS)...???

3) What happens if I use XLR > TRS into that 1/4" unbanaced Input...???

thanx very much,


mark4man

[Chris Daly]

hi mark4man
I downloaded the mackie desk operating guide Mackie - Onyx 1640i
on page 7 it refers to using a powered speaker like the bose from the aux send jack 1 in pre fader mode. from what i can ascertain the Bose has a RCA line level input as well as XLR for Mic - the Mic is likely to be too sensitive - in any case the Bose appears to have a volume pot for level. XLR balanced involves Gnd , Positive also called Hot and Negative also called Cold - a balanced connection is great for long cable runs. You could investigate using a break out box if you have to use balanced into unbalanced connection. Or design your own. A DBX 150x manual talks a lot about unbal and balanced loads XLR and phone jacks and provides schematics showing how an op amp can change bal to unbalanced. dbx® Vintage downloads

Hope this helps / chris

[Ferrit37]

hey Guys,
you might find this of some use:
Sound System Interconnection