Calibrating Input Level for Plugins

Figured this deserved its own thread.

First I would recommend calibrating to 0.707vRMS=-12dBFS here: https://thegearforum.com/threads/calibrating-helix-native-input-level.816/

This will give you an accurate calibration for using Helix Native, and seems to work very well for Neural DSP+Mercuriall Plugins. You can also use this calibration, and set STL's Amphub and Tonality plugins input level to +6dB and have those properly calibrated.

I should mention that the DI chain can be calibrated in any number of ways - I followed @James Freeman 's Helix guide as it seems to be a calibration level that works for several different modelling platforms while still retaining some headroom. On several amp models, they really come to life with the input cranked like this. Whats bizarre is that you'd have to be an absolute maniac to set your input level like this, as I get the internal clipping light on basically all the time. There's enough amp models that I own the real equivalents of and at +12dB most of them behave much more similarly to the real thing (take SJ50's red channel for instance, the real amp should barely have a clean sound in it). At +12dB I still get a nice range of tones from the plexi style amps too, and they also behave much like my Marshall's do.

I seem to think a couple of models got a bit farty and needed their level dropped, but I'm finding it better to keep the input at +12dB and drop, rather than keeping it at 0 and guessing every time.

If you haven't had much luck with Amplitube in the past, I'd recommend trying this.
 
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Amplitube: 0.707vRMS = 1vPeak = 0dBFS.
Helix: 0.707vRMS = 1vPeak = -12dBFS.

Nobody visits the 'science' threads, it's a bunch of mumbo-jumbo for nerds.
Just don't complain about gain accuracy when you use a random interface with random gain settings and random input/output levels.
Play hard... don't clip.
:LOL:
 
The sad parts is manufacturers don't think people are smart enough nor model gain accuracy is important so they just don't bother with numbers.

There's this, and then there's needing to set the input WAY higher than what we'd normally feel comfortable with. Like, having to turn a signal up that much, with loads of clipping lights is instinctively going to make you feel like something is wrong somewhere.
 
It's a "Don't ask questions that we can't answer and you can't apply" situation.

There's this, and then there's needing to set the input WAY higher than what we'd normally feel comfortable with. Like, having to turn a signal up that much, with loads of clipping lights is instinctively going to make you feel like something is wrong somewhere.

Right, in hardware land everything is internally calibrated/compensated to work accurately with the models and have enough ADC headroom.
With software they should consider the typical ADC headroom of Instrument inputs of audio interfaces and account for that, Helix Native does, Amplitube doesn't. ¯\_(ツ)_/¯
 
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Right, in hardware land everything is internally calibrated/compensated to work accurately with the models and have enough ADC headroom.
With software they should consider the typical ADC headroom of Instrument inputs of audio interface and account for that, Helix Native does, Amplitube doesn't. ¯\_(ツ)_/¯

I feel like the Softube Marshall's are similar in this regard. I think they're excellent emulations and they're often sold for $20-30. When I get time I'll see if I can make a guess (their support wasn't much help :( )
 
Softube Marshall's are similar in this regard. ... I'll see if I can make a guess
Usually, they compensate by halving the input variable from the ADC, that's the simplest thing to do in code (right shift >>).
So 0db, -6db, -12db, -18db, etc.
Your interface should already be calibrated to 0.707v = -12dBFS for headroom.
 
hmm I dont think all of the Amplitube models are modelled at a consistent input level. IMO Brit 8000 sounds way too gainy at +12dB.

On the other side, the match my JMP2203 I have to boost the Softube JMP by about 18dB. So far they seem to need even more of a boost than Amplitube does.
 
For future reference it will be good to have a link to James Freeman’s post being referred to by OP:
 
I’d like to better understand how to use James’ method for any amp sim. I have only read this thread and the first page of the other, so I will do more reading before I start to ask questions. No opinion from me on whether to merge threads or not.
 
Will post more in depth soon, but doing a big 2203 shootout. Checked my calibrations several times, both plugging directly into units and through my reamp chain.

The HX Stomp and HX Native are both calibrated to sound the same. The calibration method in the 1st post is all correct and behaving as it should. If I want the Brit 2204 model to match the gain of my real JMP2203, I need to drop the Helix (native or HX Stomp) input by 12dB. I believe as well as the bright cap, there is about 12dB more gain than I would expect from this circuit.
 
If I want the Brit 2204 model to match the gain of my real JMP2203, I need to drop the Helix (native or HX Stomp) input by 12dB.
The real JMP2203 is that low gain? Maybe something is not right?
Is that also the case when plugging the guitar directly into the amp?
 
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Hmm.... sounds like there's something wrong.
Is that also the case when plugging the guitar directly into the amp?

At first I thought this was wrong, but I've checked:

-Guitar into amp
-Reamp into amp
-Guitar into HX Stomp
-Reamp into HX Stomp

Guitar and reamp into amp sound the same
Guitar and reamp into stomp sound the same

DI into HX Native and reamp into HX Stomp sound the same
 
Ren And Stimpy Nicksplat GIF by NickRewind
 
The real JMP2203 is that low gain? Maybe something is not right?
Is that also the case when plugging the guitar directly into the amp?

Gain on the real JMP2203 feels correct to what I'd expect, not super high gain or anything but just sort of classic Marshall. If I plug the guitar directly into HX Stomp's 2204 and set the gain to 6, its flubby and gained out.

Here is just quick chords plugging directly into both with preamp gain at 6

 
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