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Input levels spike to red with 0 input gain

Discussion in 'Axe-Fx III Discussion' started by kenneth Osmanich, Dec 22, 2018.

  1. kenneth Osmanich

    kenneth Osmanich
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    Hi all...I am new to the Fractal world and I jumped right in to the Axe FX 3...and loving it!

    I seem to be having issues setting the input gain on channel one, even if I set it to 0 in the Setup/In, out page...
    it still shows spikes to the end of the red when I go to the layout page to find the input meter.

    If any mods are reading this it seems to me the input gain staging should be found in the "Input" block which seems to only contain the gate parameters.

    As well the input meters should be on the same page as the one where you adjust the input gain....

    Still neither of those suggestions will address my issue.

    There seems to be some reduction in gain from turning the knob from 100% down to 0% but not much...this can't be right somehow...is this a bug or just me?

    Cheers,Ken
     
  2. Tumatauenga

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    From pg5 of the manual:

    A red LED on the input meter indicates a level of -6dB, which is safely below clipping. Adjust the input trim so your loudest playing “tickles the red”

    Do you hear any clipping when it hits the red? With 6db of headroom once you go into the red, I think what you’re seeing is fine.

    If you saw that on the output side I’d be more concerned - you should be more careful there.
     
  3. ccroyalsenders

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    You want it hitting the red.
    This "gain" has zero effect on your tone or signal level hitting any blocks (until below 5%). It is simply to optimize SNR. Any adjustments you make to this input are automatically compensated back to unity in the AD before any processing.
    This is bar none the most misunderstood parameter in the Axe-Fx.
     
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  4. kenneth Osmanich

    kenneth Osmanich
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    Thanks for the reply...but I am still not sure why I would be getting signal and the red going right up to max. ( with heavy playing) even when I have the input gain set to zero...?
     
  5. kenneth Osmanich

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    Thanks for the reply...but I am still not sure why I would be getting signal and the red going right up to max. ( with heavy playing) even when I have the input gain set to zero...?

    The compensation is working fine and the sound just gets muddier if I set the input gain to 100%...but the overall metering and sound level does not change to much.
     
  6. kenneth Osmanich

    kenneth Osmanich
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    The input meter on the screen is the one that goes all the way to red pinned with heavy playing...the led meter above the output knobs just barely touches orange until I max it out and it still doesn't hit red.
    It seems the meters do not jive with each other...
     
  7. FractalAudio

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    Set the Input Trim so the meters ON THE FRONT PANEL tickle the red when strumming fairly hard. Nothing else matters.
     
  8. FractalAudio

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    What "Input Meter" on what "screen"? I think you're confusing what the meters are.
     
  9. vangrieg

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    Well, Axe-FX III specs list maximum input level at 16 dBu. The input meter will show red at -6 dB, so even if you set Input trim to 0, you’ll “tickle the red” at 10 dBu hitting the instrument input, which is, if I’m not wrong with math, about 7 volts peak to peak, 2.5 volts RMS - quite possible with heavy playing and a high output passive humbucker.

    As long as there’s no clipping, there’s nothing to worry about.
     
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  10. kenneth Osmanich

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    When you press layout from the home page...then zoom out ...there is an input meter at the top of the screen, that is the one that pins to red when i play hard.
    I take it this is a different meter than the one on the front panel that only goes to orange for me even with my PRS with Duncan distortions installed.

    When I set the input gain to 100% on the I/O page of setup I still can't get a red led on the front panel but I can hear a bit of mud...when I set the gain to 0% I am still getting an orange led with hard play on the front panel and I am still getting red on the screen meter.
     
  11. FractalAudio

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    That's the Output 1 meter.
     
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  12. chris

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    That is an Output meter, and is dependent on the overall level of your current preset. This is normally adjusted using the Amp block Level.

    As mentioned in the manual and above, the Input meter is the hardware meter on the front panel above each input, and also adjusting that Input is a signal/noise ratio, not an actual perceived level change.
     
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  13. kenneth Osmanich

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    That explains it...Thanks for all your help...it seems I just have the output gain structure to hot...easy rix!
     
  14. Warrior

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    Is there an issue if I have to set my Input Trim to 99.2% (for my Strat) to tickle the red when strumming fairly hard?
     
  15. FractalAudio

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    No. Means the pickups are weak. My Strat is the same.
     
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  16. kenneth Osmanich

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    Thanks for your help...I would still like to repeat my request for input gain staging to be in the "In" blocks of the presets...even if it remains global and also an input gain meter on that same page would make all this easy and more straight forward.

    I am calling the Axe FX 3 the best thing ever!...even with that one semi issue ...this unit is stellar!
     
  17. #17 notalemming, Dec 22, 2018
    Last edited: Dec 22, 2018
    notalemming

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    Not needed on a per preset basis. Set it once to your hottest guitar on it's hottest pickup & forget it.
     
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  18. kenneth Osmanich

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    I realize that ...but it just seems intuitive to have the input gain staging in the input block...even if you only need it once in a while.

    It is the least straight forward thing I have found about this unit...coming from a soundman's perspective...everything else makes sense to me...
     
  19. chris

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    but it's not "gain staging." it's signal to noise ratio. that's why it's global. set it to your loudest guitar, move on.

    you CAN add or reduce input to the grid in the Input block if you want to, per preset. and that is actual level which will drive your amps harder, etc.
     
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  20. kenneth Osmanich

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    ...So there is no actual input gain staging ...that is now confusing me more...

    In any case I now have all my levels within visually decent levels without pasting the red on the outputs and hitting the orange pretty steady on the input, still can't make a red happen on the input led's though ...but the sound is glorious ...so I a can live with the confusion.

    Cheers,
    Ken
     

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