Numpty DI Box/Phantom Power Question

Unorthodox

I ordered a DI Box (Behringer Ultra DI100), to try and eliminate some ground loop issues from my guitar to the first pedal. However I've just noticed it seems to provide phantom power.

So my question is, will I damage my pedals when running from the DI box via XLR to jack?

ICBM

It doesn't provide phantom power, it accepts it - so the box can be powered by the desk via the XLR.

There will be no voltage on the 1/4" jacks.

But what you're doing with it is unlikely to work properly because the signal level on the XLR output when converted back to 1/4" will be much lower than guitar level.

What you need is an isolating transformer.

steamabacus

ICBM's right. I use these from Orchid Electronics. Very good quality, UK manufacturer and cheap, too. They do a stereo version as well.

Unorthodox

Excellent

Cheers ICBM, stuck a battery in it and everything works great. No more interference!

EDIT: By the way, probably should've mentioned this before but, the only reason I need this is because it's a Variax guitar and I wanted to use both the VDI and jack outputs at the same time. The VDI caused the jack output to have some ground loop interference on it. Everything is rosy now though

EDIT 2: No noticeable difference in sound when using the DI box.

ecc83

Aha!

The thot plikens! ......Just FYI you cannot have a hum LOOP with just a guitar. Hum, yes but not a loop.

Good to see Orchid get mention!

Dave.

ICBM

ecc83 said:

The thot plikens! ......Just FYI you cannot have a hum LOOP with just a guitar. Hum, yes but not a loop.

You can if you split the signal to two different amps, both of which are grounded.

Unorthodox

ICBM said:

ecc83 said:

The thot plikens! ......Just FYI you cannot have a hum LOOP with just a guitar. Hum, yes but not a loop.

You can if you split the signal to two different amps, both of which are grounded.

I think that's what was essentially happening with the Variax. The ground lift on the DI box fixed everything anyways, so I'm pretty sure it was a ground loop issue.

ICBM

So are you going from the XLR output to a pedal input via a converter cable? If so I'm surprised it gives you enough level - but if it works, it works!

I sometimes do a sort-of similar thing with my Rickenbacker which has stereo outs, but I put one side through a DI box and straight to the desk from there, so it remains low-impedance/unbalanced.

Are you using any overdrive/distortion on the side which goes through the DI box? I don't with the Rick, that's always clean and the other side is the one which has dirt on it.

Unorthodox

Currently the VDI is going straight into the HD500x (not being used as an input on the HD500x, just merely connected so I can change tunings and models via the footswitches). The jack is going into the DI box, out via XLR to jack, into an EHX Tortion pedal and then into the guitar in of the HD500x.

There seems to be plenty of signal there, even with the EHX Tortion in by pass. I tried quickly switching the cables around a few times to see if my ears could hear any difference in possible signal loss, but I couldn't detect anything.

ecc83

ICBM said:

ecc83 said:

The thot plikens! ......Just FYI you cannot have a hum LOOP with just a guitar. Hum, yes but not a loop.

You can if you split the signal to two different amps, both of which are grounded.

Yup! But we did not know that from the first post.

My interjection was in the interests of general clarity. So often on forums we do not get the full picture until a lot of teeth have been drawn, and sometimes never!

Dave.

ICBM

ecc83 said:

Yup! But we did not know that from the first post.

That's true, but I did guess that he was going to be running two amps in some way .

I have to admit that the casual use of terms like "earth hum" by guitarists whether or not it has anything to do with the problem can make it difficult to identify the cause sometimes though!