Input Trim

Also since FW 16 and newer, it is in my experience even more important to set the Instrument Input 1 and the Global Input Gain correctly for his guitar (pickups). To perceive all facets of the individual presets and their were potential. why? Rehearsal is that the Input 1 control acts more as a saturation control for the AD converter and the level meter can only represent this inadequately. Effect is that if I set the level as described in the manual, (set the value so that the red LED at maximum play only looks up from time to time) I come to the value around 95. This leads in the perception that all amp sound too saturated, hardly show differences and spatiality.
As many have already described it here in the forum.

If the saturation is set too high for the AD, an overdrive protection takes effect.
And this has the effect of compression in my perception.

Maybe Cliff can include a level for the saturation of the AD to hit the sweet spot better.

For me, I have now tested the value 30 as the best value. Super spatial and natural perception of the individual amps with FRFR. And only minimal interspersion noise even with high gain amps.

I tend to play the low gain amps like Fender VOX, yet the high gain amps are really fun with this setting. IMO

The Global Input Gain for my Strat is set to 0.478.

Checks that times for you on you makes similar experiences.

Cheers
 
Also since FW 16 and newer, it is in my experience even more important to set the Instrument Input 1 and the Global Input Gain correctly for his guitar (pickups). To perceive all facets of the individual presets and their were potential. why? Rehearsal is that the Input 1 control acts more as a saturation control for the AD converter and the level meter can only represent this inadequately. Effect is that if I set the level as described in the manual, (set the value so that the red LED at maximum play only looks up from time to time) I come to the value around 95. This leads in the perception that all amp sound too saturated, hardly show differences and spatiality.
As many have already described it here in the forum.

If the saturation is set too high for the AD, an overdrive protection takes effect.
And this has the effect of compression in my perception.

Maybe Cliff can include a level for the saturation of the AD to hit the sweet spot better.

For me, I have now tested the value 30 as the best value. Super spatial and natural perception of the individual amps with FRFR. And only minimal interspersion noise even with high gain amps.

I tend to play the low gain amps like Fender VOX, yet the high gain amps are really fun with this setting. IMO

The Global Input Gain for my Strat is set to 0.478.

Checks that times for you on you makes similar experiences.

Cheers
AFAIK A/D Input Level has no effect on the levels within presets and/or saturation of amp models except for settings of less than 5%. Global Input Gain on the other hand will increase the level going into presets. Needing an A/D input level value of 95% suggests guitar pickups with extremely/uncommonly low output.
 
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AFAIK A/D Input Level has no effect on the levels within presets and/or saturation of amp models except for settings of less than 5%.
This is what I have always heard and said, and is what the manual says.

However, very recently Cliff commented on a post where I said this. He said if you are overdriving the A/D converter then it will affect the sound.
That setting is only for optimizing the A/D converters. It's a compensated control and has no effect on the actual sound unless you set it at values of 5% or less (according to the manual).

It most definitely has an affect on the sound. If it is set too high (red LEDs lighting constantly) the A/D converter is clipping. Depending upon the guitar, picking style, strings, etc. you may need to lower it to 10% or less.
It kind of makes sense but since the manual specifically says otherwise, it's a bit confusing.

Maybe @Admin M@ can confirm with Cliff and adjust the wording in the manual if required?

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This is what I have always heard and said, and is what the manual says.

However, very recently Cliff commented on a post where I said this. He said if you are overdriving the A/D converter then it will affect the sound.



It kind of makes sense but since the manual specifically says otherwise, it's a bit confusing.

Maybe @Admin M@ can confirm with Cliff and adjust the wording in the manual if required?

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Hmmm - testing here with my strongest guitar (tickles red with A/D Input Level at 40%), I can get digital clipping in the signal by turning A/D input level up high - it's not really a gain increase though - it's digital clipping type crackle. With my weakest guitar (can't tickle red even with A/D level at 100%), I don't get any digital clipping at any A/D input value (for this guitar I still leave A/D level at 40% as I think it still gives me a level which is acceptable for Axefx to process it, and for the guitar to sound correct). I've never owned a guitar that needed anywhere near 95% to sound like it should but maybe the OP is worried about it not tickling the red which, from what I've experienced, is not a absolute necessity.
 
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Hmmm - testing here with my strongest guitar (tickles red with A/D Input Level at 40%), I can get digital clipping in the signal by turning A/D input level up high - it's not really a gain increase though - it's digital clipping type crackle. With my weakest guitar (can't tickle red even with A/D level at 100%), I don't get any digital clipping at any A/D input value (for this guitar I still leave A/D level at 40% as I think it still gives me a level which is acceptable for Axefx to process it, and for the guitar to sound correct). I've never owned a guitar that needed anywhere near 95% to sound like it should but maybe the OP is worried about it not tickling the red which, from what I've experienced, is not a necessity.
I don't have a guitar that can push consistently in the red even at 100%...
 
This is what I have always heard and said, and is what the manual says.

However, very recently Cliff commented on a post where I said this. He said if you are overdriving the A/D converter then it will affect the sound.
You're both right. It is implied in the instructions that you're not clipping the input converter. In other words, assuming you're not clipping, the input level doesn't affect the input signal strength to the grid (except at the lowest levels, where the compensation arithmetic becomes tricky).

But that's not to say the signal isn't affected. Obviously the noise characteristics will change as you adjust that (poorly named, by the way :)) input level. And, if you're clipping the converter, that will have a significant effect on the signal.
 
You're both right. It is implied in the instructions that you're not clipping the input converter. In other words, assuming you're not clipping, the input level doesn't affect the input signal strength to the grid (except at the lowest levels, where the compensation arithmetic becomes tricky).

But that's not to say the signal isn't affected. Obviously the noise characteristics will change as you adjust that (poorly named, by the way :)) input level. And, if you're clipping the converter, that will have a significant effect on the signal.
Thanks - that's what I was thinking it had to be.
 
Cooper just addressed this in his latest "Fractal Friday" video. I don't want to paraphrase what he said and get it wrong, but he did confirm what I've been doing by saying if you have a hot-output guitar like a Majesty, you may need to set it as low as 10%, which to "tickle the reds" when using the gain boost on the guitar (set it for your hottest guitar and just leave it there) is what I have to do.
As for how the manual is worded, since the previous part instructs you to set it so it "tickles the red," as long as you don't go any further than this, (because doing so will clip the converter, which is what I understood Cliff to be saying), any lower settings won't affect the level you hear, because it's compensated (which Cooper also explains.)
Could it be written a bit clearer? Yeah, I think so.
 
The saturation of the AD converter is not visible, the LED display only shows me the level.

We have to distinguish between saturation and level.
An AD converter works best when the audio signal produces a saturation of 0 to 100%.

The LED display shows us how good our input signal is and with the Input 1 control we can adjust the signal with the appropriate amount to set the saturation optimally. To prevent too much saturation, a limiter is set behind the Input 1 control.

This means that if I turn the knob above the maximum saturation, I raise the lower volume ranges. And lose dynamic range.
On the one hand you lose dynamic range and the interferences are amplified.

Knowledge
Just because I can't reach the red LED in the level, I can still reach a 100% saturation at the AD!

When that is, however, I can not recognize and at too high values 95, red LED flashes from time to time, severely limited playing dynamics and the amps are played only with high input signals.

If I'm not right about that, happy to make a correction.

Hence my wish that the saturation is displayed on the AD in the range of Input 1 control on the UI.
As a value or bar to be able to see a trend.

Or a peak value for the saturation with hold function for a few seconds.
 
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Best use of the working range in the AD converter to the analog signal.

0 to 1V = 0 to 256bit (perfect)

If the overall signal is low, I do not use the full potential and quality of the converter.

0 to 0.6V I use only 2/3 of the converter, above is empty.

If I raise the signal (the operating point) too much, I compress the audio signal because above 100% the limiter takes effect. More noise in the signal and the feel, the dynamics on the strings is gone.

0.5 to 1V. 1/2 of the 256 bit steps are wasted for noise und missing Dynamik.
 
Yeah that's just normal gain staging. Saturation typically implies a non-linear response. You want to stay in the totally linear range of the converter's input for the truest copy of the analog signal. Too high and you'll clip the input signal. Too low and you lose resolution, although with the resolution of 24 bit audio you'd have to be WAY low to noticeably affect it. SNR is affected at both ends of the input level setting. As you clip the input, you're hard limiting the dynamic range and therefor raising the noise level in the input signal. With the setting too low, the input circuit's self noise level becomes higher relative to the input signal. You want to find that Goldilocks spot between.

"Tickling the red" is a decent quick and dirty way to set it. Using the DI waveform in a DAW is the best way to find that sweet spot precisely.

Like Cooper said in his video, set it for your hottest pickups and leave it.
 
So then what's the best way to see visually if there's actually clipping or not, the levels in the Out 1 block, Headroom in the Amp block, other??
 
So then what's the best way to see visually if there's actually clipping or not, the levels in the Out 1 block, Headroom in the Amp block, other??
For input clipping (the issue being discussed above is input, not output), it's not easy. The Axe-FX has no input clipping indicator, only a "close to clipping" indicator. About the best you can do is check the level at the start of the processing chain in the grid to make sure it's below 0 dB. Or, see Mr. Fender's post above where he examined recorded waveforms in a DAW.
 
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Cooper has also only reproduced what is in the manual.
I do not want to stress this further here.
To determine the correct value, I will simply halve the value where the red LED flashes briefly. Then it fits.
 
Seems we're all on the same page - what threw me a bit in the recent newer post was the word "saturation", which, for me doesn't describe what happens with A/D level too high (maybe just my interpretation of the word). With A/D input level at 45% my strongest guitar starts generating good ole ugly/nasty digital clipping crackle in the signal as opposed to what I would think of as saturation - the crackle starts off very slightly and intermittently, then gets continuously worse as the level rises above 45% to 100% with this guitar. I think a good way to set A/D level is to listen for when these very slight intermittent crackles start appearing in a simple in/out patch while adjusting A/D Input and back off a couple of % when u start to hear it - I can easily end up having it set too high with the "tickle the red" observation only". For higher gain, having A/D level a bit too high is not something I would notice, but for clean cleans, that intermittent crackle can problematically show up - it was one of these super clean patches that revealed I had A/D about 10% too high for years. For a lower output strongest guitar the default 50% is probably good in most cases and generating any digital clipping won't even be possible.
 
If you look at Mr. Fender's analysis, you can see there's no "saturation". Despite what the manual says, it clips pretty hard. Like you, I don't "tickle the red". I adjust so the red never comes on. In the absence of a clipping indicator, that's really the only safe way to avoid clipping.
 
Seems we're all on the same page - what threw me a bit in the recent newer post was the word "saturation", which, for me doesn't describe what happens with A/D level too high (maybe just my interpretation of the word). With A/D input level at 45% my strongest guitar starts generating good ole ugly/nasty digital clipping crackle in the signal as opposed to what I would think of as saturation - the crackle starts off very slightly and intermittently, then gets continuously worse as the level rises above 45% to 100% with this guitar. I think a good way to set A/D level is to listen for when these very slight intermittent crackles start appearing in a simple in/out patch while adjusting A/D Input and back off a couple of % when u start to hear it - I can easily end up having it set too high with the "tickle the red" observation only". For higher gain, having A/D level a bit too high is not something I would notice, but for clean cleans, that intermittent crackle can problematically show up - it was one of these super clean patches that revealed I had A/D about 10% too high for years. For a lower output strongest guitar the default 50% is probably good in most cases and generating any digital clipping won't even be possible.
Saturation because a portion of the input signal is fed to the A/D via the controller. So that the A/D can convert the input signal in the best possible way.
Saturation = filling quantity?
But I noticed that at very high values 90 to 100% no overdriving is noticeable, but the sound image seems compressed, all presets dull and all amps very similar. Although the red LED does not light up.
 
Saturation because a portion of the input signal is fed to the A/D via the controller. So that the A/D can convert the input signal in the best possible way.
Saturation = filling quantity?
Nope. Saturation means asking a circuit to produce more signal than it's capable of. That's when distortion starts.

You're thinking about using as much of the range of the A/D converter as possible. That's a good thing, because it lowers the noise floor. But in the case of electric guitar, it's not so important. The noise that your guitar produces is usually much stronger than the noise of the A/D converter.


But I noticed that at very high values 90 to 100% no overdriving is noticeable, but the sound image seems compressed, all presets dull and all amps very similar. Although the red LED does not light up.
That's because of the A/D converter's built-in limiter. It prevents the converter from going into saturation (clipping) when it gets hit with a too-strong signal.
 
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