Calibrating Input Level for Plugins

[Josetxu]

Hi everybody.

I've just discovered this forum because I was having questions about the correct input level in my interface so the virtual amps reacted faithfully to my different guitars. I use a Focusrite Scarlett 6i6 2nd gen with S-gear, Neural DSP Tone King and sometimes HX native. If I've understood correctly, I should apply a gain of +1db for Neural DSP and HX native, and about 13db for S-Gear (for getting 0dBfs)? if so, what's the best way to do it accurately for the stand-alone versions? at least Neural DSP only gives you a numerical value for the level control, but not a measurement unit, so I don't know if they're dBs or not.

Thanks for all the useful information given in this post.

 

[James Freeman]

Hi and welcome Josetxu.

Yes, Focusrite Scarlett has +12.5dBu inputs (at minimum gain) and Helix expects +11.5 dBu so you need to boost by +1dB before Helix Native.
Or not, 1dB is not much.

and about 13db for S-Gear (for getting 0dBfs)?

That would be correct for SPICE based plugins where they expect 0.0 dBFS as 1 virtual volt, but this is somewhat outdated approach and most plugins boost by +12dB internally so your audio interface has headroom for humbacker guitars.

Focusrite Scarlett is one of the most wide spread audio interfaces on the market so many manufacturers probably test their plugins with it.
My suggestion is leave the interface gain at minimum and you are good to go with most plugins and all your guitars.

 

[MirrorProfiles]

Sigh, Jason still isn't grasping this. I've tried telling him in the comments but he just assumes I'm a troll and deletes it (LOL).



Anyway, he says the ToneX Pedal has an 8.6dB boost after the converters. and he also says he is using a Focusrite Clarrett 4 Pre interface with the gain down, and this is what he's calibrated for.

Clarett+ 4Pre

Clarett+ 4Pre is a versatile and sonically true 18-in/8-out audio interface for the complete creator.

focusrite.com

Spec's for that are +15dBu, which in my experience is more headroom than IK products want to see.

Anyway, looks like ToneX just got an update which should help (the pedals) but I also suspect that people may just get more confused by this

 

[SwirlyMaple]

The only plugin I’ve ever seen attempt to deal with this in a competent way is ReValver. Its input section had a field where you actually entered the Vrms value of your pickups (expecting you to measure this directly from your guitar), and then you pressed the calibrate button and strummed hard with the same knob settings that produced the measured voltage.

You could save different measurement values for different pickups, and as long as you did that quick auto-cal, it would adjust the input gain to match what it should be for your measured value.

Still a bit imperfect, but a heck of a lot better than what all other plugins are doing for input level consistency (i.e., nothing).

 

[James Freeman]

Sigh, Jason still isn't grasping this. I've tried telling him in the comments but he just assumes I'm a troll and deletes it (LOL).

I'm not clicking that.
Sad is all about the google paycheck, he couldn't care less about your wisdom.

 

[MirrorProfiles]

I'm not clicking that.
Sad is all about the google paycheck, he couldn't care less about your wisdom.

THE FINE FOLKS AT GOOGLE

 

[James Freeman]

I tried to find the point in his 30min video, okay so IK reverted the 9dB boost but was this the problem in the first place?
The new IK interface (+10.5 dBu) might have 3-5dB difference from the Tonex Pedal so you still have to fiddle blindly with input trimmers.

Why don't they post some useful numbers already FFS.

 

[MirrorProfiles]

I tried to find the point in his 30min video, okay so IK reverted the 9dB boost but was this the problem in the first place?
The new IK interface (+10.5 dBu) might have 3-5dB difference from the Tonex Pedal so you still have to fiddle blindly with input trimmers.

Why don't they post some useful numbers already FFS.

A bit baffling that between his back and forth with THE FINE FOLKS AT IK MULTIMEDIA, no one thought to just get the multi meter out.

Not sure where the 15dB comes from, but it sounds like his reamp box is calibrated for slightly less headroom than his DI (the ToneX example sounds undergained vs his amp). And whatever IK’s intended levels are, they’re definitely on the lower headroom side of things (their LED meters when making models asks for hot signals, and we know what Amplitube is like too).

So yeah, I think for best results with IK multimedia, you want to err on the side of 12dBu or less.

It really winds me up how he always says the DI level doesn’t matter, and then wonders why everything else needs adjusting.

Shouldn’t wind me up so much, but we have someone shilling for IK and just giving shoddy advice out.

 

[Josetxu]

Hi and welcome Josetxu.

Yes, Focusrite Scarlett has +12.5dBu inputs (at minimum gain) and Helix expects +11.5 dBu so you need to boost by +1dB before Helix Native.
Or not, 1dB is not much.


That would be correct for SPICE based plugins where they expect 0.0 dBFS as 1 virtual volt, but this is somewhat outdated approach and most plugins boost by +12dB internally so your audio interface has headroom for humbacker guitars.

Focusrite Scarlett is one of the most wide spread audio interfaces on the market so many manufacturers probably test their plugins with it.
My suggestion is leave the interface gain at minimum and you are good to go with most plugins and all your guitars.

Thanks James, I've always heard the "adjust the input gain until it's red only with really hard picking" and always thought it wasn't the right way. Now I've learned not only the correct way to do it but also a little of the "science" behind (the dDFS meaning, the relationship between the input sensivity and the dBFS, etc.) thanks for your post and all the other contributions.

 

[zolko60]

If you look at Axe I/O One Amp Out specs section, you will find:
"

• Output level: 0 dBFS corresponds to -3.5 dBu"

That is about 14dB too low for reamping.

It explains their Tonex Pedal input sensitivity prior to the last HUGE firmware update which was 15dB too loud according to Jason Sadites.
JS video spoiler: Fine guys at IK multimedia finally got the right instrument level and it is now better than before but they still claim it is too low.

 

[MirrorProfiles]

If anyone is using Mercuriall plugins and wants to get the most accuracy from them, I made a spreadsheet where you can enter your input headroom value, and you can get a value to set the plugin's input level.

Mercuriall Input Level Calculator.xlsx

Shared with Dropbox

www.dropbox.com

 

[pipelineaudio]

Sigh, Jason still isn't grasping this. I've tried telling him in the comments but he just assumes I'm a troll and deletes it (LOL).



Anyway, he says the ToneX Pedal has an 8.6dB boost after the converters. and he also says he is using a Focusrite Clarrett 4 Pre interface with the gain down, and this is what he's calibrated for.

Clarett+ 4Pre

Clarett+ 4Pre is a versatile and sonically true 18-in/8-out audio interface for the complete creator.

focusrite.com

Spec's for that are +15dBu, which in my experience is more headroom than IK products want to see.

Anyway, looks like ToneX just got an update which should help (the pedals) but I also suspect that people may just get more confused by this

I have serious problems with the Tonex software requiring a PILE of input gain boost after the capture to get it to sound anything like the original. We had a thread on here of different ways to set levels to try and keep that from happening, but it still did, and could be pretty drastic. I wonder if this update fixes that

 

[JiveTurkey]

Sigh, Jason still isn't grasping this. I've tried telling him in the comments but he just assumes I'm a troll and deletes it (LOL).



Anyway, he says the ToneX Pedal has an 8.6dB boost after the converters. and he also says he is using a Focusrite Clarrett 4 Pre interface with the gain down, and this is what he's calibrated for.

Clarett+ 4Pre

Clarett+ 4Pre is a versatile and sonically true 18-in/8-out audio interface for the complete creator.

focusrite.com

Spec's for that are +15dBu, which in my experience is more headroom than IK products want to see.

Anyway, looks like ToneX just got an update which should help (the pedals) but I also suspect that people may just get more confused by this

Is this the video where he is down with back pain but still correcting people on the internet

 

[pipelineaudio]

Everytime someone posts his videos, I imagine that Pinecreek Channel on youtube's "Bloviation Alert" siren going off

 

[MirrorProfiles]

I have serious problems with the Tonex software requiring a PILE of input gain boost after the capture to get it to sound anything like the original. We had a thread on here of different ways to set levels to try and keep that from happening, but it still did, and could be pretty drastic. I wonder if this update fixes that

How much level it needs depends on your reamp chain, but if it needs a lot of adjustment then I’d recommend adjusting something on that end of things.

 

[pipelineaudio]

We did, we tried more than what IK recommended and less, and pretty extreme in both directions and it was still happening, I'll see if I can dig up the thread. Also, regardless of the levels, there was a pretty substantial treble adjustment needed as well, like 6-12db worth

 

[pipelineaudio]

How much level it needs depends on your reamp chain, but if it needs a lot of adjustment then I’d recommend adjusting something on that end of things.

Here's the other thread, looks like you already saw this one https://thegearforum.com/threads/calibrating-input-level-for-plugins.816/page-6

 

[MirrorProfiles]

Is anyone else able to measure the headroom of the Kemper DI and reamp chains with all settings set to unity/0?

I got the same dBu value for each, which presumably means they've done everything correctly. It just seemed way lower headroom than what I've seen from other interfaces. I do remember the Kemper DI being fairly easy to clip so maybe its correct, but if someone can verify?

 

[MirrorProfiles]

Git Studio

Similar to “Git+Processing”, but here the instrument signal is sent out at studio level, which is much louder than the original level. Thus, no separate DI box is needed to record the pure instrument for reamping purposes. Since the instrument volume is high, the recommended leveling of “Clean Sens” in the Input Section is important.

From the Kemper manual ^

If things are at 0, that would explain why I'm getting a small amount of headroom on the DI's. I'm going to double check values again before confirming but maybe I can find a clean sens level that allows for more headroom when recording DI's

 

[MirrorProfiles]

Measured again, checking everything as I go and verifying against other devices.

With Kemper settings at 0 (clean sens, reamp sens), I’m measuring the headroom to be at 5dBu.

To get it set up for 12dBu, I had to set clean sens to -6.9dB and reamp sens to 7.1dB (sending a -15.9dB sine wave in via SPDIF)

5dBu seems really low to me - the fact I’m measuring it on input and output makes sense though - it means it works as intended and will preserve gain levels. Might be good if someone can verify this though.