Hi Carlaz
carlaz wrote:Honestly, this stuff seems to work well, though I have no good sense of how things compare to the corresponding hardware amps
Nice to hear that it works. You can compare to Youtube demos. Just set the amp to the same settings as shown in the demo and compare if its about the same amount of gain. If you don't agree with my suggestion, just change the value for this model to something you think is right
carlaz wrote:though it does often seem like "related" groups of AmpliTube models tend to share similar "gain offsets", except when given amp models were actually produced in different times in the software's history (e.g., the British Lead S100 (+12) is one of original Hendrix models, along with the "American Vintage" Fender-style models (all +5), while the JH Gold (-12) and the SilverTwelve (+/-0) were later additions in the 2nd-gen Hendrix collection.).
Yes there are definitely some "trends" going on for certain packs and release times. But this "trend" also includes that there is nearly always one or two amps that jump out
The old models (like Brit Lead...) were pretty tricky since they dont react like the real amp at all (in my opinion). Also for some amps it was hard to find a good demo to compare to.
carlaz wrote:Matthias: I do have some questions about your video and your "AT5 Amp Input Gain List" document, if you would be willing to address them.
I did not understand the reason for the added +0,79 dB. What is that?
1 Vp = 0.707 VRMS = -0.79 dBu
Lets say your interface has a max headroom of +12dbu = 0dBFS and is set to min gain.
boost 12db and you will get 0dbu = 0dbfs
boost 12.8db and you will get 1V AC (or Vp) = 0dbfS
I had to choose a startingpoint where everyone can calibrate its interface to and after that everyone is on the same point (but everyone needs different settings to get there...)
I chose 1Vp as my startingpoint since most amp sims use SPICE in a certain way and its typical for spice to work with this calibration.
In the end 0.8db is not much difference in this case. I doubt anyone can hear a difference...
carlaz wrote:You do say in the comments to your YouTube video that trying to come up with similar "gain offset values" for the distortion pedals "got really messy and didnt worked out as hoped/expected, so i stopped". Could you -- or would you -- elaborate on that? I presume some of the problem is that, besides the pedal models (like the amp models) having been produced at different times in the software's history, there's also the issue of people basically never using a pedal except in front of an amp, which makes it complicated to guess about what is really happening.
I don't think i'm able to do this. One reason is what you said. Next reason is that there are some pedals (satch) that are presumably modded versions. And another reason is that i think (at least on some pedals) IK worked with a little "magic" on the output knob, that makes it even more difficult to compare.
And last but not least, to be honest i just dont want to. It should be IK Multimedias job to do this....
My recomendation is to put the pedals after the "1V AC calibration" and before the "amp model gain correction"
A other user said, they compare best to his real 808, DS1, SD1 when they are used around +14dBu = 0dBFS
carlaz wrote:Though perhaps this has something to do with those crazy boost values for the Brian May amp models? As best as I remember, in real life, May always hits those amps with his treble booster, and the hardware version of the "KAT" treble booster pedal that is modeled in AmpliTube does put out 29 to 33 dB of boost, depending on the setting.
The brian may model has a boost switch on the back with on/off and high/low. I guess IK modeled it without any boost activated, so i wanted to iclude this...
https://www.youtube.com/watch?v=72KOn91gQaoThere is not much information on this amp in general but i found this:
Of course, a remote treble booster is a vital part of his sound too, and Vox has included an internal boost circuit that can be switched in and out via the included footswitch. This isn't the same as a simple overdrive pedal, but a design that adds to the basic signal - around 46dB in this case - which is a significant hike in level to say the least.https://www.musicradar.com/reviews/guitars/vox-brian-may-ac30-25579+23 for the low boost setting is just a guess i have to say.
But yeah, i think a better way to do this is to add his pedal in front of the amp.
Perhaps it's not least because I have no examples of real, hardware amps to try alongside the software models that are intended to emulate them. 
vs. -12 for a number of other models) that one gets the sense that the various AmpliTube models can only have been designed and tested with some variety of different input levels.
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I suspect one reason that IKM hasn't done/doesn't do this is that values for different pieces of gear over time are, in fact, all over the place. 
Assuming that their archives old the necessary production notes, even if they now retroactively adjusted all the values to a common standard in a new release, that would blow up everyone's backward compatibility. It could only realistically be implemented in an "AmpliTube 6" release -- though I would suspect any AT6 release to still be some ways off in the future.
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