Digital out into Monitor or FOH

[scrinson]

Hi I was hoping one of you guys could help - could I use the L6 AES / EBU digital out into a standard XLR input i.e. a monitor or FOH mixer?

 

Thanks

[PeterHamm]

No, don't bother trying to mess with digital connections to connect to a PA, even if it has Digital Ins. Too much can go wrong with digital signals in that environment.

XLR out to the mixer (WITH PHANTOM POWER OFF) or 1/4" out to Direct Box to mixer is the way to go.

[scrinson]

Thanks Peter

[mikisb]

No, don't bother trying to mess with digital connections to connect to a PA, even if it has Digital Ins. Too much can go wrong with digital signals in that environment.

 

XLR out to the mixer (WITH PHANTOM POWER OFF) or 1/4" out to Direct Box to mixer is the way to go.

 

Could you please explain what could go wrong and what do you mean with "that environment"?

 

I'm just building two ultralight active 12" Coax FRFR cabs, where i choosed Hypex 2channel moules as poweramp. They each have have a freely configurable DSP for  each of the two channels and a digital in (XLR as well)

 

I bought them hoping to use he digital link Helix-DSP to avoid multiple DA/AD conversions: DA in the Helix for analog out, AD in the amp before the DSP and DA in the amp after the DSP. Using a digital link would avoid 2 of 3 conversions wich normally should'nt be bad.

 

Unfortunally, the cabs are'nt ready to test yet, but in home hifi or car hifi environments as well as using a personal computer/DAW, i never experienced any problems using digital connections. Should'nt a digital link provide some advantages as less cnversions, less noise receiving cables....? Of course, sample rates and bit depth sohould be compatible ;)

[PeterHamm]

Could you please explain what could go wrong and what do you mean with "that environment"?

 

I'm just building two ultralight active 12" Coax FRFR cabs, where i choosed Hypex 2channel moules as poweramp. They each have have a freely configurable DSP for  each of the two channels and a digital in (XLR as well)

 

I bought them hoping to use he digital link Helix-DSP to avoid multiple DA/AD conversions: DA in the Helix for analog out, AD in the amp before the DSP and DA in the amp after the DSP. Using a digital link would avoid 2 of 3 conversions wich normally should'nt be bad.

 

Unfortunally, the cabs are'nt ready to test yet, but in home hifi or car hifi environments as well as using a personal computer/DAW, i never experienced any problems using digital connections. Should'nt a digital link provide some advantages as less cnversions, less noise receiving cables....? Of course, sample rates and bit depth sohould be compatible ;)

 

 

1. You will never hear the extra D/A -> A/D conversion. You just won't hear the difference.

2. Digital connections are fiddly about the cable they travel over and there is much that can go wrong at each end.

3. At home where the connection is basically an installation, not a moving target, it's great. On stage, it's not a good idea, and most importantly, it's just overkill. A balanced analog connection sounds fantastic.

4. This is usually a case where the user feels they have to use every jack and output on Helix they can or they aren't getting their money's worth, and convincing themselves they can hear a difference when in fact in a blind test they probably couldn't.

 

I go even further. I won't use my XLR outs on Helix live to the board at all. I use the 1/4" out to a D.I. because there are a multitude of problems that can happen with the XLR signal (phantom power, impedance and level mismatches mostly) which simply don't happen when you feed the house with something from a decent quality D.I. And, yes, it sounds the same unless you are using a 25' or longer cable between the Helix and the D.I. So use something 10' or shorter. It sounds the same.

[mikisb]

Hi Peter,

 

thanks a lot for this detailed answer! :)

[scrinson]

Peter,

 

My issue was that I am running out of connections!!!

 

I have my acoustic going into return and out on send to a di then FOH

 

My electric goes into guitar in then out on xlr mono to FOH and out on 1/4 inch mono to a FRFR monitor behind me.

 

I would like to put my vocals through as well which would be no problem for xlr in and I guess I'll try one of the sends for the output.

 

My initial thinking was that I'd use XLR out for the vocals and then use the L6 as an analogue output for the electric with a conventional XLR cable

[amsdenj]

Good digital coax cables are often expensive, stiff and short. Otherwise you can get a lot of dither and digital errors. You'll also need to match the Helix with whatever the PA provides for digital input: bit rate and depth - that may not always be possible and is one more place where things can go wrong during setup. Also the coax RCA jacks aren't really gig hardened for cables that are going be stepped on, moved around, plugged in and unplugged often, etc. They're more appropriate for fixed, stable installations.

 

I'm not sure what your application is, but it might be that you want your vocal mic, electric guitar and acoustic all running into Helix (no problem) so that you can use the Helix Headphone output as your local personal monitor mix. Then you need three to five (depending on what needs to be stereo) separate outputs to individual channels in the PA for the FOH mix. This could work if you use the two XLR outputs, one for vocal and one for either guitar. I'm assuming you don't need both instruments at the same time. Different patches would control what goes out the guitar XLR output.

 

The other option is to try to get a personal monitor mix from the PA. Most modern digital mixers make this pretty easy, and you can often control your own mix with your phone.

[scrinson]

Hi and thanks Amsdenj,

 

So this is what I'm trying to do

 

 

Acoustic ( in on return and send to FOH via Di)

 

Electric ( in on guitar and out via XLR left and 1/4 out to a FRFR as a cab behind me)

 

This is where I'm confused - I didn't think I could use the other XLR out for vocals as this would be the right hand element of the stereo signal? - is this an incorrect assumption?

 

I'm happy taking a monitor feed from FOH but I still want the FRFR behind me.

 

I'm not using stereo for now and you're right I won't be using both guitars at the same time.

[PeterHamm]

Peter,

 

My issue was that I am running out of connections!!!

 

I have my acoustic going into return and out on send to a di then FOH

 

My electric goes into guitar in then out on xlr mono to FOH and out on 1/4 inch mono to a FRFR monitor behind me.

 

I would like to put my vocals through as well which would be no problem for xlr in and I guess I'll try one of the sends for the output.

 

My initial thinking was that I'd use XLR out for the vocals and then use the L6 as an analogue output for the electric with a conventional XLR cable

 

 

I would suggest to you that trying to use any one piece of gear (other than a mixer, obviously) for that many signals is going to become an exercise in logistical frustration... where you're thinking so much about your signal chain that you can't just get lost in the music.

 

I would just send the vocals through the house. Let 'em deal with that at the board.

[CraigGT]

My initial thinking was that I'd use XLR out for the vocals and then use the L6 as an analogue output for the electric with a conventional XLR cable

 

As far as I'm aware the L6 link carries a digital signal, you can't plug it into a normal mixer channel just because it uses the same connector.

 

Craig

[PeterHamm]

As far as I'm aware the L6 link carries a digital signal, you can't plug it into a normal mixer channel just because it uses the same connector.

 

Craig

 

 

This is correct, but you CAN plug the digital output from Helix into a mixer's AES/EBU input if one exists (although you probably can't send it over a snake, so don't try), or if it's a Line 6 mixer, some of those I think have a L6Link input.

 

But, again, don't do this. This is a bad idea in a live environment.

[scrinson]

I would suggest to you that trying to use any one piece of gear (other than a mixer, obviously) for that many signals is going to become an exercise in logistical frustration... where you're thinking so much about your signal chain that you can't just get lost in the music.

I would just send the vocals through the house. Let 'em deal with that at the board.

The reason I would like to use the helix is so that I can take advantage of the effects, I don't believe I'd be thinking about the signalchain once I have it working. Totally understand though if you think what I'm trying to achieve is pushing a bit too far

[CraigGT]

This is correct, but you CAN plug the digital output from Helix into a mixer's AES/EBU input if one exists (although you probably can't send it over a snake, so don't try), or if it's a Line 6 mixer, some of those I think have a L6Link input.

 

But, again, don't do this. This is a bad idea in a live environment.

 

I was under the impression that the OP was referring to a mic input.

 

I know that you're right in what you say about using digital links in a live environment but I come from a telecoms background where we send much higher bit rates along cables that we make ad-hoc over 100's of meters with no problems whatsoever. I'm always amazed when people start discussing the varying sound qualities of SPDIF cables!

 

I guess it's one of life's mysteries, why can't we get reliable digital audio or why can we still not make reliable PSU's?

 

Craig 

[xmacvicar]

On 8/5/2017 at 2:23 PM, PeterHamm said:

No, don't bother trying to mess with digital connections to connect to a PA, even if it has Digital Ins. Too much can go wrong with digital signals in that environment.

XLR out to the mixer (WITH PHANTOM POWER OFF) or 1/4" out to Direct Box to mixer is the way to go.

 

@PeterHamm when running your 1/4 out to a DI box, then to FOH, is your 1/4 out on the Helix set to mic level?

[DunedinDragon]

2 hours ago, xmacvicar said:

 

@PeterHamm when running your 1/4 out to a DI box, then to FOH, is your 1/4 out on the Helix set to mic level?

That's generally not necessary.  Most DI boxes have attenuation settings, but I've never had to use them and just send a Line level signal.  I will often go with Mic level when sending direct from the XLR through a phantom power blocker to the board simply to be consistent with the other XLR inputs coming into the board.

[PeterHamm]

4 hours ago, xmacvicar said:

 

@PeterHamm when running your 1/4 out to a DI box, then to FOH, is your 1/4 out on the Helix set to mic level?

1/4" output doesn't have Mic level. It has Line and Instrument. I leave it set to Line Level.