Cable to connect Fischer IEM body pack to A&H QU-PAC

[dickiefunk]

Hi, I'm looking to buy a cable to be able to use my Fischer IEM belt pack in stereo. The specs for the Fischer In Ear Stick say it is configurable for balanced mono signals or unbalanced stereo signals.
The QU-PAC has balanced outputs so do I need a Y cable with two female balanced XLR's to a single unbalanced male XLR cable?
Fischer sell a cable for this but it doesn't state the spec. Also, the Fischer Y cable is £42 which seems pretty expensive for a 1.6m cable!?

I have been looking around to buy a cable but can't find an alternative to the Fischer cable so far!?

[Wonks]

There are various Fischer belt packs. Which one?

And are you just wanting a mono out from the desk to go to both sides of the IEMs or is is 2x mono outs (L&R stero signals) from the desk to go to one XLR input for a stereo IEM mix?

If you look at the pdf manual they have diagrams for the various cables. E.g. page 3 of this manual:

https://www.fischer-amps.de/downloads_e ... 16_web.pdf

[dickiefunk]

Thanks. It is the Fischer In Ear Stick. I need two female XLR outputs from the QU-PAC to one single male XLR into the Fischer In Ear Stick.

[Wonks]

Then the bottom cable on page 3 of that pdf is the one you want. I’m not sure if you’d get one ready made from some other source apart from Fischer that’s not custom made.

Easy enough to make up a DIY one.

[shufflebeat]

You could also just buy a regular TRS(x1)-TS(x2) “insert” cable of the desired length and route whichever stereo mix you’re monitoring from to the “alt out” jack sockets in settings.

Personally, I’d make up an adaptor, TS(x2)-XLRm, stick it on the end of a mic lead and run that from “alt out” as described straight into the headphone amp.

[Sam Spoons]

That was going to be my suggestion but if you are doing that why not make a 2 x XLRF to 1 x XLRM lead like the one in the user manual which would have locking connectors at both ends. It's no harder to make and not much costlier...

[Wonks]

I’d definitely have an XLR so it locks in at the IEM controller end.

[dickiefunk]

I’d definitely have an XLR so it locks in at the IEM controller end.

Yes I want to have the XLR end for this reason

[James Perrett]

The diagram on page 3 of the pdf makes certain assumptions about the XLR output that are not necessarily correct in all cases. You need to know exactly how the output of the A&H is designed in order to make the right cable. It certainly wouldn't work with the XLR outputs of my A&H desk or the XLR outputs on my MTR90 but it would work with many other pieces of gear (including other A&H desks).

[dickiefunk]

The only thing I know about the A&H QU-PAC outputs are they're balanced?

[Wonks]

James is talking about transformer balanced outputs (James could have made it clearer) where you'd only be connecting to one end of the transformer with the cable wiring shown, and so you'd get no output. But connecting to an electronic servo-balanced output at one end will be fine.

If you really want to be sure, connect pin 3 to pin 1 in the XLRs at the mixer end.

[James Perrett]

James is talking about transformer balanced outputs (James could have made it clearer)

Not necessarily transformer balanced... Some electronically balanced outputs require pin 3 connected to ground if they are feeding an unbalanced input while others would potentially give problems if you connect pin 3 to ground. That's why, when going from balanced to unbalanced connections, it is essential to read the manuals for the devices you are connecting together.

As Hugh's signature says, "In my world, things get less strange when I read the manual... "

[Wonks]

Though the QU-PAC manual doesn't actually inform you of the type of balanced output connection it actually has. The block schematic only shows it's electronic, with no transformer involved.

[James Perrett]

Though the QU-PAC manual doesn't actually inform you of the type of balanced output connection it actually has. The block schematic only shows it's electronic, with no transformer involved.

I just checked the manual and page 14 says

Professional equipment provides ‘balanced’ connections for
maximum interference rejection over long cable runs. If you
are connecting to ‘unbalanced’ equipment then make sure
the XLR pin 3 (signal cold) is linked to pin 1 (signal ground).

So it appears to possibly use the same output circuit as my mixer where leaving pin 3 disconnected results in a very noisy signal.

[Wonks]

Fair enough. So also link pins 1 and 3 in each of the mixer end XLRs (but not the Fischer end XLR).

[shufflebeat]

Using TS jacks in the 1/4” “alt outs” usefully does all the grounding for you. if you’re concerned about attachment then wrap a velcro strap (yuk!) round the mic cable you’re using and the handle of any case your Qu Pac is in. I doubt it will be an issue, though.