XLR to 1/4" mono plug question

[Vito Corleone]

When is it necessary or at least recommended to use a transformer when either plugging a device with a 1/4" output into a XLR jack or vice versa?

I've got all sorts of connectors and transformers and have interchanged all of them at various points in time.  Just wondering what is the proper way to do things and what are the dangers of doing them improperly?

[trevcda]

Anytime there is a potential for 48V phantom power to be back fed into your 1/4" inputs. Most, if not all, 1/4" jacks do not have protection against this voltage.

[dboomer]

 

Transformers add isolation.  So they can block dc (as in the case of protecting from phantom power and disconnect you from direct electrical connections for safety and eliminating ground loops.

Transformers can match impedances for better transfer of power and can add (or cut) voltage levels as in lo-z mic to hi-z input (which does both)

 

You can also create a balanced signal from an unbalanced one.

Transformers always create distortion and loss of fidelity (from very small amounts to large ... depending) so you don't want to add one to the chain unless you need it to do one or more of the above functions

 

So what do you want to do? 

[Vito Corleone]

Just need to do things like running a drum module with a 1/4" output to a snake input and running XLR snake lines into 1/4" channel inputs in a mixer.

[agedhorse]

You need to determine levels and then decide which solution is the appropriate one.

[dboomer]

Your best bet would be to use a DI box that will handle line levels. You don't necessarly need a transformer box.  Usually active DI's will handle more input level than transformer boxes in the same price range.

 

Whirlwind Hot Box would be a good choice.