XLR-1/4" line transformer

[mjbphotos]

My live set up: 2 guitars with balanced line outs to XLR-1/4" line transformers into the 2 inputs on my Radial PZ-Pre. I could use standard TS-TS cable for my Taylor, but the 1/4" output on my 12 string is crackly, so I use the XLR output.
So 2 songs into my 12-string set of songs yesterday, sound just stops! I jiggled the cable, the connections on either end, nothing! So I quickly switched back to the 6-string and finished the gig.
At home, checked the 12-string, everything was fine ((plugged into my audio interface) until I tried plugging it in with the same XLR-1/4 transformer, totally dead, not working at all. How can one of these adapters just stop working? Not sure what brand it is, I see them on Amazon for anywhere from $8 and up. Will a $23 HOSA really be better than an $18 Parts Express vs a no-name brand?

 

[ecc83]

My live set up: 2 guitars with balanced line outs to XLR-1/4" line transformers into the 2 inputs on my Radial PZ-Pre. I could use standard TS-TS cable for my Taylor, but the 1/4" output on my 12 string is crackly, so I use the XLR output.
So 2 songs into my 12-string set of songs yesterday, sound just stops! I jiggled the cable, the connections on either end, nothing! So I quickly switched back to the 6-string and finished the gig.
At home, checked the 12-string, everything was fine ((plugged into my audio interface) until I tried plugging it in with the same XLR-1/4 transformer, totally dead, not working at all. How can one of these adapters just stop working? Not sure what brand it is, I see them on Amazon for anywhere from $8 and up. Will a $23 HOSA really be better than an $18 Parts Express vs a no-name brand?

Hi Mike why are you using transformers? I take it the guitars are actives and I see why you need to use the XLR on one but that could be a simple XLR to TS cable? The cheapo transformers I have seen and used are for mic level signals, ~600R to 50k and so give about a 19dB boost. Surely the Radial does not need that?

As for failure mode? The actual transformers are incredibly wee and if not really secure I can see the sub hair D wires snapping!

If perchance they are just 1:1 traffs you can get better ones from OEP Walter transformers (CPC do 'em I think) Need to put them in a tin but at least these components are 1kV isolation proofed! Would not trust a Zon 20 quidder to be so.

I have a few kicking around if you want to do a bit of DIY 'tronics?

I do them a disservice https://www.farnell.com/datasheets/1872256.pdf TWO kV!

Dave.

 

[rob aylestone]

I'm guessing the transformer is for the low-Z guitar XLR out going to the 10 Meg Ohm ¼" input? Transformers just dying without vibration, impact or something electrical hasn't ever happened to me - a bit odd?

 

[mjbphotos]

Taylor guitar has balanced TRS output. When I use a standard TS-TS cable, the signal seems lower volume then when I use a TRS-XLR with 1/4" line transformer adapter (but maybe that's an auditory illusion?!)
12-string - I use the XLR output (as I mentioned, the 1/4" is noisy), and use a standard XLR-XLR cable (I have tons of them) with the 1/4" line transformer. Should I just use an adapter that is not a 'line transformer'?

The Radial doesn't NEED better inputs signals, but I get an even set of inputs by doing it this way, no messing around with levels/EQ when switching guitars.

 

[Gtoboy]

I wouldn't think a transformer would be necessary , but easiest thing to do is try without and see what results(or hear rather).

 

[ecc83]

Taylor guitar has balanced TRS output. When I use a standard TS-TS cable, the signal seems lower volume then when I use a TRS-XLR with 1/4" line transformer adapter (but maybe that's an auditory illusion?!)
12-string - I use the XLR output (as I mentioned, the 1/4" is noisy), and use a standard XLR-XLR cable (I have tons of them) with the 1/4" line transformer. Should I just use an adapter that is not a 'line transformer'?

The Radial doesn't NEED better inputs signals, but I get an even set of inputs by doing it this way, no messing around with levels/EQ when switching guitars.

Well, whatever works for YOU Mike works! I would like to know what exactly the transformers are, i.e. their ratios and intended use?
One thing is sure, there is nothing in that setup that could cause a transformer to fail. You have just been incredibly unlucky! As this is a 'live' rig and the traffs are cheap as chips maybe carry a spare? Doubt you will EVER need it!

Oh and, the signal loss with the Taylor is almost certainly real. It might use a centre tapped OP transformer in which case a TS cable would only use one half, 6dB loss. If it used a symmetrical amplifier output, again only using one half.

Dave.

 

[mjbphotos]

Well, whatever works for YOU Mike works! I would like to know what exactly the transformers are, i.e. their ratios and intended use?
One thing is sure, there is nothing in that setup that could cause a transformer to fail. You have just been incredibly unlucky! As this is a 'live' rig and the traffs are cheap as chips maybe carry a spare? Doubt you will EVER need it!

Oh and, the signal loss with the Taylor is almost certainly real. It might use a centre tapped OP transformer in which case a TS cable would only use one half, 6dB loss. If it used a symmetrical amplifier output, again only using one half.

Dave.

Oh, I know the signal level drops with the Taylor using a TS cable compared to a balanced cable, just not sure about it with the line transformer in place. If the failure had happened at a gig where I was going to play the 12-string again in another set, I would have tried plugging it in directly into the board via XLR. I could do the same thing with the Taylor, of course, but I prefer the sound I get when putting the Radial inline as I can adjust the EQ for a less piezo-y sound. No future gigs booked at this point ...

 

[ecc83]

Oh, I know the signal level drops with the Taylor using a TS cable compared to a balanced cable, just not sure about it with the line transformer in place. If the failure had happened at a gig where I was going to play the 12-string again in another set, I would have tried plugging it in directly into the board via XLR. I could do the same thing with the Taylor, of course, but I prefer the sound I get when putting the Radial inline as I can adjust the EQ for a less piezo-y sound. No future gigs booked at this point ...'t Yes, yes! Mike! but I still don

Yes, yes Mike but I STILL don't know what those fekkin' transformers are!

Dave.

 

[arcaxis]

Hey Mike, if your transformer widget is anything like the ones I have, they come apart pretty easy. Small Phillips screw retains the the XLR side and the 1/4" TS unscrews from the main barrel. I first tried just unscrewing the 1/4" plug side, but the wires inside twisted up. I then removed the XLR and then unscrewed the 1/4" plug which allowed the wires and the XLR connector to spin freely. I'm going to guess that using this in a live situation with an XLR cable floppy around that the 1/4" plug could have been turning in the main barrel and eventually broke a wire. If the transformers come apart like mine it's an easy solder fix if you're up to it.

 

[mjbphotos]

Hey Mike, if your transformer widget is anything like the ones I have, they come apart pretty easy. Small Phillips screw retains the the XLR side and the 1/4" TS unscrews from the main barrel. I first tried just unscrewing the 1/4" plug side, but the wires inside twisted up. I then removed the XLR and then unscrewed the 1/4" plug which allowed the wires and the XLR connector to spin freely. I'm going to guess that using this in a live situation with an XLR cable floppy around that the 1/4" plug could have been turning in the main barrel and eventually broke a wire. If the transformers come apart like mine it's an easy solder fix if you're up to it.

Good idea.
So I just undid the thing (3 set screws), and there's only 1 wire! The TS sleeve relies on the metal barrel for the grounding to the XLR end. And yes, that wire just 'fell' off the solder blade - there are 4 tabs on the XLR end, 2 of which are connected with a very tiny wire. I may try fixing it, but as I don't have any gigs lined up right now, I'll just order a couple of replacements.

 

[ecc83]

Good idea.
So I just undid the thing (3 set screws), and there's only 1 wire! The TS sleeve relies on the metal barrel for the grounding to the XLR end. And yes, that wire just 'fell' off the solder blade - there are 4 tabs on the XLR end, 2 of which are connected with a very tiny wire. I may try fixing it, but as I don't have any gigs lined up right now, I'll just order a couple of replacements.

Brill. Now...WTF are they!?