FM3 Input Level .... Tickling the Red .... how much ?

DJD100 said:
Google: Voltage can also be expressed in decibels, such as dBV when Vref = 1 V RMS (root-mean-square) or dBu when Vref = 0.775 V RMS. For example, 6 dB represents a doubling of voltage.
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I stand corrected...20 * log (V2/V1) = 6 dB for V2/V1 = 2. Doubling of voltage = quadrupling of power = 6 dB.
 
ben ifin said:
Quick question re: FM3 Input Level " Tickling the Red ".

(a) if I run the Pad at 6db ..... it never ever hits the Red regardless of how hard I play.

(b) if I run the Pad at 0db ..... it Flash's Red whenever I hit or chug hard but never stays on the Red permanently.

What would be considered "the best" way to set it (?) (a) -or- (b) (?)
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Hi Ben, I used since the beginning (b). Recently, I tested the (a) situation and I like the sound more... it's subtle... so my vote for (a)!
 
I'll point out the the waveforms from my testing were clipped even when the red light was not blinking red at the 12db setting, so it's best to confirm via DAW if max dynamics and the cleanest cleans are desired.

That said, the waveform clipping at the 12db pad setting was minimal, but quite apparent.

Lots of variables, pups, strings, picks, guitar setup etc...
 
I think there is some real over thinking it here in this thread. Use your highest output guitar, select whichever setting gets closest to the red coming on occasionally or close to, then you’re done.
 
Again, lots of variables, pups, picks, strings, pup height, string gauge and tuning, guitar design, bridge and nut, etc, etc...

...so I'm just saying some cases you can clip without lighting the clip indicator, which may or may not be audible depending another number of variables LOL!

I believe it's likely that you can hit the front end limiter in some cases without lighting the clip indicator.
 
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DJD100 said:
I recorded stuff into Pro Tools with relatively hot passive humbuckers (Duncan JB's), and I found that I needed to set the input pad to 18db to get pristine unclipped waveforms, so it's best to check by recording into a DAW and zooming in to examine the waveform IME.

I used Input Block to Output Block in the FM3, and played hard with both fingers and picks, but didn't just bang on the strings etc.
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In1 --> Out1 is not how to determine if you're clipping the input, I think. Record the DI directly using USB and you won't see it being squished.
DJD100 said:
Again, lots of variables, pups, picks, strings, pup height, string gauge and tuning, guitar design, bridge and nut, etc, etc...

...so I'm just saying some cases you can clip without lighting the clip indicator, which may or may not be audible depending another number of variables LOL!
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I think that's why you're thinking that you're clip even though the FM3 isn't indicating you are.

Correct about there being a ton of variables though
 
It doesn't matter as you can easily confirm whether you're clipping the output or not.

You can use any output, analog, digital, or USB, being mindful of your gain staging.

The idea is to keep the output levels conservative to isolate the input.
 
If there was any input clipping issue like that, how would people use fm3 input with boost pedals? But you can do it "like with the real amp" (according to fractal support), and its very often more than 10 db boost on top of your pickups signal
 
shredhead said:
If there was any input clipping issue like that, how would people use fm3 input with boost pedals? But you can do it "like with the real amp" (according to fractal support), and its very often more than 10 db boost on top of your pickups signal
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Fractal generally has some noise reduction and a limiter on their guitar inputs ("secret sauce"?), to try and protect the A/D from someone doing exactly that, as that's the totally wrong way to do it!

You should take anything in the input chain or guitar in at the correct level, and then in the digital domain go ahead and goose the level 10db into the amp block as desired, or just use the amp block's built-in boost etc. These modelers are not tube amps.
 
DJD100 said:
Fractal generally has some noise reduction and a limiter on their guitar inputs ("secret sauce"?), to try and protect the A/D from someone doing exactly that, as that's the totally wrong way to do it!

You should take anything in the input chain or guitar in at the correct level, and then in the digital domain go ahead and goose the level 10db into the amp block as desired, or just use the amp block's built-in boost etc. These modelers are not tube amps.
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Quote from Mark (support@fractalaudio.com)

"The FM3 input reacts just like a guitar amp input, using a BB Preamp as a boost in front should certainly not cause any damage."
 
You can also check out what this dude is saying here
Seems like he probably should really know what he's talking about, right?
 
shredhead said:
If there was any input clipping issue like that, how would people use fm3 input with boost pedals? But you can do it "like with the real amp" (according to fractal support), and its very often more than 10 db boost on top of your pickups signal
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You should set the input at max level, hence with boost pedal active. Sure, no harm to input even with blasting level but the distortion will be audible! :)
 
shredhead said:
I could also add a quote from Cooper Carter here:
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That quote is not correct. You absolutely can clip the input with just a guitar if the pad is set too low. If you use boost pedals out front you need to adjust the input pad accordingly to allow more headroom. The input can handle +/- 5v when the pad is set to its highest setting.
 
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