Helix XLR output question

[mikisb]

Hi,

 

i'm buiding a FRFR amp with a hypex 2channel DSP/ampmodule. The module has no hardware volume, just a fixed gain of 16 dB.

Volume is variable by DSP config software but this is not usefull everywhere.

 

To get about full power, i would need to feed it with about 6,3V = 18 dBU. Does anybody know what's the standard output level of the XLR outs on nthe Helix?

I know that there can be no absolute response as this level will probably depend on the amp, effects... - but there must be a standard level?

 

The Helix actual output with factory presets ans  global volume at max is far away from getting all the power out of the amps.

[GlennDeLaune]

You would probably want to run the XLR outs at Line level and the master Volume knob of the Helix somewhere between 12 noon and full on. That should be plenty loud. It does depend on the patch though. There are several gain stages so if what I just suggested isn't loud enough (I suspect it will be) you can start using the level controls in the paths.

[mikisb]

Hi Glenn,

 

thanks for your advice!

I've set the XLR out at Line level and have to turn the main volume at noon just for bedroom playing, so i will not get full power out of the amp even at max.

 

In understand that the Helix XLR output depends on all the possible gain stages, so my question is difficult to respond.

As a reference, we could take your patches (wich are pretty good balanced in level)  to know their output at main volume at max.

 

Perhaps a part of the problem is that i does'nt know the range of the Helix concerning levels as there is no visual indicator for it.

If for example your patches only use 50% of the maximum output, it would make sense to boost them all up to +6 dB.

 

For the power amps i can increase gain using the DSP software but this will increase noise. So the final quastion will be to rise gain in Helix or in DSP to get minimum noise.

 

Sorry if some things sounds a bit confused, as it's not easy to me to express straight in english.

[mikisb]

OK, i did a quick 'n dirty test to see some kind of benchmark for me:

 

Base: A guitar with a pretty high output (selfmade) humbucker at Neck-Position (comparable in output level to a SD SH4).

 

Helix: A completly empty channel , all levels at 0

 

Hypex DSC 2.400: Gain reduced -24 dB so the rumble in the room stays reasonable. As the gain (adjustable -96 to +18 dB) affects the gain behind the dsp, there sould be no effect on the amps input.

 

XLR cable from Helix to the Hypex PSC 2.400

 

"playing" continous on the empty E-string near the point where the string starts touching the frets while slowly rising the gain on Helix output-section.

 

Result: At about +16 dB distortion starts. Can't say if it's from the Helix or the PSC but i suppose that the DSC's maximum input level is reached. (18 dBU says the user manual wich means about 6.15 V eff. or 17.4V s-s)

Does'nt make a difference if i boost the output block 16 dB or the output block 6 dB togehter with global EQ 10 dB.

 

So just for myself, this ist the first benchmark in the "Helix output question" ;)

 

So if i keep all my presets as they are, i have to add about 10 dB in the output section or the global EQ to get the full power out of the amp module,as they are (supposed) about 6 dB more powerful than the clean signal.

I also could rise the gain by  software/USB in the amp module, but this gives me more noise even when i don't need the power, so it seems to be more elegant to do this with the Helix only when full power is needed.

 

But after all, this let's me think about general levels in Helix with all the possible gain stages. To avoid level overload at the output, there must be a lot of headroom in the system. But with to much headroom, we have a lack of dynamics and resolution when it comes to digital processing. Wonder how line 6 managed all this (should'nt be a simple task) and renew my wish for level meters at least for the input and the output stage.

[Jellyott]

I've got two of the same amps (in Barefaced FR800s).

 

How have you found the Helix, is it capable of driving the amps to clipping? How do you have the internal gain in HFA set?

 

I'm moving from a Kemper, and my gut feeling is that the Kemper has way more output than the Helix...

[jbuhajla]

 

I'm moving from a Kemper, and my gut feeling is that the Kemper has way more output than the Helix...

That shouldn't be the case. A line level output is pretty much standard across audio component platforms. With Helix, you can set the output to Line or Mic level.