Configuring at Axe-Fx 3 for wireless (e.g., differential line in on Input 2 "left")

@kgk, I'd open a case with Shure. For my GLXD it states this:
  • To replicate the output level of a guitar, unity gain is -18 dB for the ¼" output
Since the ULXD & GLXD's are a bit different, I'd ask them what unity gain should be on the 1/4inch output. I believe the Receiver will be the same, but I suspect the body pack transmitter needs to be set to 0db.

I've opened cases before with Shure, they are super responsive and will definitely point you in the right direction for Unity gain structure on the ULXD.
 
unix-guy said:
What is a "differential signal"? I've never heard that term before.
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It's the more engineering term for balanced. The signals appears 180-degrees out of phase on the plus and minus lines instead of a signal line accompanied by a "static" ground line. Well done, they can mitigate ground loops. Reasonably done, they ignore coupled noise that couples onto both the plus and minus. Good for common-mode noise environments (Google it) to better preserve SNR.

peace,
boogie
 
kgk said:
It has two gain settings, if I recall, one in the Tx, and one in the Rx.
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I don't think so. From the link you provided:
Optimized for any input source, ULX-D eliminates the need for transmitter gain adjustments.
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kgk said:
Are you saying that if I add the gain back on the Rx side you expect that the manufacturer wants the "instrument" jack to have unity gain?
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I make no claims about what the manufacturer wants. I'm only saying that every wireless I've ever used gave me unity gain when the receiver output was dimed.
 
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Rex said:
I don't think so. From the link you provided:

I make no claims about what the manufacturer wants. I'm only saying that every wireless I've ever used gave me unity gain when the receiver output was dimed.
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I took a look at it and the transmitter has "input pad" that offers 0dB or -12dB (I should have recent firmware). Also remember that the receiver has two outputs, and these are (a) XLR [with pad to switch between "line" and "mic"], and (b) "instrument," and they don't formally state what these actually do in terms of end-to-end gain. But I like @biskitboy's idea to ask Shure, I'll do that.

From my recollection of the older firmware it was much more adjustable than the 0dB or -12dB. I didn't recently check the gain on the receiver side to see what they're up to over there (it has new firmware too, that I didn't really examine), I'll do that soon.
 
The axe expects a guitar signal for a guitar, not a line signal. I don’t see any reason to try to give it something other than designed.
 
chris said:
The axe expects a guitar signal for a guitar, not a line signal. I don’t see any reason to try to give it something other than designed.
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It can process guitar level, line level, and digital inputs, so you have your choice of all three!
 
kgk said:
I took a look at it and the transmitter has "input pad" that offers 0dB or -12dB (I should have recent firmware).
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If you're using the 12 dB cut, and you want to hit the Axe with the same level that a wire would provide, crank Output Level on the Input block to +12. Unless the firmware is compensating for that cut on the receiver end (it's easy to check that; play with and without the cut, and see whether there's an audible volume change).


kgk said:
Also remember that the receiver has two outputs, and these are (a) XLR [with pad to switch between "line" and "mic"], and (b) "instrument," and they don't formally state what these actually do in terms of end-to-end gain.
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XLR on the Mic setting will probably give the same level as the Instrument output. It's easy to chack that, too. :)


kgk said:
But I like @biskitboy's idea to ask Shure, I'll do that.
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Excellent idea.


chris said:
I just think this is all over thinking the basic first step: plug in the guitar.
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There's some truth to this.
 
Rex said:
If you're using the 12 dB cut, and you want to hit the Axe with the same level that a wire would provide, crank Output Level on the Input block to +12. Unless the firmware is compensating for that cut on the receiver end (it's easy to check that; play with and without the cut, and see whether there's an audible volume change).
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XLR on the Mic setting will probably give the same level as the Instrument output. It's easy to chack that, too. :)
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There's some truth to this.
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There are a few incredibly fundamental questions here, (a) what is the effective gain of the "instrument" output of the wireless, (b) what is the effective gain of the differential output of the wireless [both "mic" and "line"], and (c) how does one configure an Axe FX 3 to use [say] Input #2 left as the source of the.guitar, what I originaly asked.

So far I have heard good guesses guesses for (a), speculation on (b), and not a word about the original question, (c).

If anybody thinks the above three questions are "overthinking," I feel sad for them, as these questions are elementary.

Anyway, (a) and (b) can be answered by Shure, and (c) can be answered [I trust] by reading the 3's manual end-to-end, and I'm in the process of doing that, it's only 200pp long, so why not.
 
kgk said:
There are a few incredibly fundamental questions here, (a) what is the effective gain of the "instrument" output of the wireless, (b) what is the effective gain of the differential output of the wireless [both "mic" and "line"], and (c) how does one configure an Axe FX 3 to use [say] Input #2 left as the source of the.guitar, what I originaly asked.
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(a) and (b) can be determined to a useful degree by a few minutes of experimentation and comparison. Asking the manufacturer is also valid.

(c) is easy. If you want to use Input 2 as your guitar input, drop an Input 2 block in every preset, and connect it as the first block in your signal chain. Most of this thread has been attempts to spare you that tedium. ;)
 
kgk said:
If anybody thinks the above three questions are "overthinking," I feel sad for them, as these questions are elementary.
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In my opinion, Elementary is using the gear as designed. This thread is graduate school.
 
Rex said:
(c) is easy. If you want to use Input 2 as your guitar input, drop an Input 2 block in every preset, and connect it as the first block in your signal chain. Most of this thread has been attempts to spare you that tedium. ;)
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On the ‘FX 2 there was a single place that I changed, so it was really easy. I absolutely agree with you that there is no way that I will go through every ‘FX 3preset and change the “1” to a “2!”
 
Here is the manual:
https://pubs.shure.com/guide/ULXD/en-US
Read it. Everything you need to know is in there. (under AUDIO, SETTING RECEIVER GAIN)
On the Transmitter - you should not have to adjust the gain.
On the back of your unit it says - Inst/Aux under the 1/4" output. That's where you plug a short cable from the ULXD to the Axe FX III main input on the back.
On the transmitter, gain reduction is automatic.
On the receiver, adjust gain accordingly per instructions on the manual.
Then for confirmation, using a cable alternate between front (cable) and back Wireless) inputs to ensure levels are the same. Use the Instrument AD setting in IO to make sure your EMGs are not overloading the front end converters.
The "noise" you will get from a couple of feet of unbalanced cable in the back of your rack is less than insignificant. Unless you use a really, really poor cable. Otherwise, you will not be able to perceive the difference. The only time that's not true is if you have grounding issues. And there shouldn't be between the Shure and the Axe FX.
Good luck!
 
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I wanted to thank everybody for all of your the great advice!

I ended up using both outputs, I put the "instrument" to rear input and then put the XLR into Line 2 left, and can therefore (a) play all of the presets by default without changing anything, and yet (b) can also make my own presets and use the differential input.

I'm surprised, in passing, that wirelesses receivers don't also put out the guitar as S/PDIF, as that would be perfect for so many applications.
 
I use Input 2 - L & R for 2 channels of wireless input. Input 1 is set for AES. These 2 inputs are all fed simultaniously. If I need to use a cable I can change Input 1 from AES to Analog. All inputs can all be level match. For the analog output of most RF units Shure recomends setting the output of the channels to -12 and using the 1/4" outputs. I keep my transmitters @ 0,0 and have a 1mV in to 1mV out ratio. I have both inputs available per preset and mute the one I'm not using. I use XLR outputs for direct outs from the RF unit for recording a backup of the performance.
 
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kgk said:
I'm surprised, in passing, that wirelesses receivers don't also put out the guitar as S/PDIF, as that would be perfect for so many applications.
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Not sure of any amps or other typical gear that uses it. That’s probably why, as well as 1/4” out being the standard.
 
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