Hi,
I already asked support because its more a question than a feature request. I got the answer to ask this question here so developers can respond. Hopefully i will get an answer :)
Here is my question in short:
As with all analog modeld software there must be some kind of reference level. In my opinion especially on amp sims this is critical to get the most realistic expierience.
Can you give me this number(s) for your products? (Ampire/Pedalboard)
example: 1Vac = 0dbFS or xdbu = xdbFS
with this information + the knowlege of how much input headroom my interface has i should be able to get the best (most realistic) performance out of your plugins, without guessing how much input i need that the software reacts like the real deal.
Here it is explained in more detail why this would be important:
In real world you would take your guitar and plug it straight into the amp (not considering any pedals for now). Lets imagine you do this with a low output pickup guitar. now you dial in a clean sound but its almost on the breakup. Now without changing amp settings you plug in a high output guitar instead. The amp would start to distort and to compensate you would need to lower the gain knob on the actual amp. In real world there is no such thing like input gain.
But since we can not simply "plug into the amp" in digital world, we need an audio interface. But every interface has a different way to convert dBu to dBFS. Some have more headroom some have less.
To overcome this, you could say, "aim for (e.g.) -18dBFS". but thats also not very practical because what you do essentially is to put a volume pedal between the amp and the guitar and adjust it till your low output pickup guitar is as hot as a high output guitar and vice versa. you will loose a lot of characteristics from the guitar/player by doing it this way.
The second way to overcome this is to just look up your specs of the interface, e.g. On my Babyface Pro FS i have "maximum Headroom: 13dBu @ 0dBFS". (but as i said, this will vary from interface to interface)
The only thing i have to do that i get maximum Headroom is to set the Interface input gain to "zero gain".
I will come back to this later because now we run into a second problem for amp sims.
Im not a dev so i dont know how all this works exactly. But for me, since a software can not handle any dBu or Voltage values directly there must be a reference point set by the developer. Basicly telling the software how a certain dBFS value is related to a real world dBu value. Lets say this value is 18dBu = 0dBFS.
Now combining both informations together, i know that i would have to lower the input by -5dB in the software to "get to 18dBu=0dBFS". (i know, it may sound contraversial that its -5 and not +5 but it is like that...).
Basicly you have now removed this volume pedal caused by the interface. With this you also made sure that you keep all characteristics from different guitars, playing styles, etc. Exactly like on the real amp.
With the "second step" you made sure that when you plug in your guitar to the sim and set the gain on the amp at e.g. 5, it should now be as close as it can get to the same guitar plugged into the real amp counterpart and set to the same settings.
Its nice to be able to set the input gain to taste and experiment with it, but i think for an simulation the most important thing and first intention should be realism.
I can only guess but i think for Ampire/Pedalboard (at least for the MCM800 Model) it is somewehere around 24dBu = 0dBFS? This setting would give me the response from the model that i would expect from the real deal. (but its just a guess...)
Only downside to this is that if you set your interface input to "0 gain" you can get problems with noise but with most modern interfaces this should not be the case.
Feature Reqest:
i think the easiest fix would be to just explain it in the manual. It would be extremly helpful for people who want to use it this way. And for people who dont want to do it, they can use it like before. Nothing changed other than a bit more text in the manual :)