GT-100 Peak Level Indicator

[Ricig]

As I did with the GT-10, I do now with the GT-100...

You can make a simple patch on the GT-100 to use as a Guitar-to-GT-100 "calibration patch", complete with a peak level indicator:

1. Initialize a patch and make only the following changes to the CTL/EXP settings:
2. Assign1 = On
3. Source = Input Level
4. Source mode = Momentary
5. Target Category = Pedal Fx
6. Target = On / Off
7. Target Lo = Off
8. Target Hi = On
9. Active Range Lo = 126
10. Active Range Hi = 127

With your patch made and saved. Adjust the GT-100's Input Sensitivity (under SYSTEM menu) until your loudest playing using you loudest pickup / volume / tone settings just briefly blink the little red EXP PEDAL SW On / Off LED next to the EXP PEDAL. Basically, align your guitar's peak output voltage to the blinking of this LED.

Doing so, IMO calibrates your guitar to the GT-100. FWIW my guitar needs an -10 dB trim for Input Sensitivity.

Then try it out. Initialize another patch (Natural Clean is the default amp). At your loudest playing, there should be no distortion or overdrive.

Hope this works well for you!

[gibvel]

Cool Ricig!! Thanks!

[Landon]

Nice, I was wondering if there was a calibration for the guitar input.

[Ricig]

Nice, I was wondering if there was a calibration for the guitar input.

I didn't get too fancy with this for the GT-100. It's worth noting that the GT-PRO had a peak meter with an analog input adjustment. It would peak when the signal reached -6dB (?)

With the GT-10/100, there is no such analog input level adjustment, but there is an input level adjustment (as we know) which operates in the digital domain, i.e. post A/D conversion. On the GT-10 it's called Input Level and Presence. On the GT-100 it's just Input Sensitivity - also the same adjustment can be found on the Micro BR-80, incidentally.

If you're interested feel free to search for my various ramblings with respect to input level and these GT processors. But in a nutshell, I use the calibration patch I built to align my guitar's highest output voltage with what the GT senses as the highest input level measurement, as evidenced by the Input Level controller attaining a midi value of 127 (actually 128 on a scale from 0-127).

In doing this it is important to leave the "Assign Common" set at it's default 50/100 (see the 9th tab /assign in the Control Assign menu). This secondary input sensitivity adjustment is what you'd use after calibration if you want to skew your patch's input level sensitivity, i.e. the behavior of the Input Level control source up or down. So calibrating while this is set to 50/100 provides equal leeway in your adjustment up or down.

Another benefit of calibration is that you utilize the "full range of motion" of the Input Level control source, with peaks equal to 127 (actually 126 because you cannot set the lo active range higher or equal to the hi active range) and no voltage/no guitar output signal equal to 0/127 on the midi scale.

[4x4uk]

I didn't get too fancy with this for the GT-100. It's worth noting that the GT-PRO had a peak meter with an analog input adjustment. It would peak when the signal reached -6dB (?)

As far as I know and can determine you are correct assuming that clipping occurs at or above 0db the GT Pro Level indicator illuminates at -6db

[USAPatriot]

You always have the coolest ideas, Ricig! -Rod-

[sundance_kiddsg]

just saw this thread..
fab idea ricig.
this is gonna be my first patch..
cheers

[Ricig]

Thank you guys.

I spent a little time last night, toying with the concept further. I did a bit of reprogramming for this patch using the foot volume parameters Vol Min and Volume Max. I was thinking it'd be nice to see where the in-process input level measurement stood as I calibrate. So what I ended up doing was to wire the vol max parameter to the input level controller. This now indicates a signal level as a % of the maximum 127 midi value. In contrast I wired the Vol Min parameter inversely so that it now displays headroom as a % of the maximum 127 midi value. I also disabled the wah so that when peaks are attained it doesn't "cock the wah" so to speak (some irony there as too much input level indeed contributes to a cocked-wah preamp tone (GT-10) as well as the inability to clean up a clean preamp at its default setting of drive = 50). I also disabled all sound, ie set foot volume to zero as well as place the FV at the beginning of the FX chain.

Now, if you cursor to the Foot Volume effect in the FX chain as you calibrate you see your signal level and available headroom % move in real time. At peak flashes, the signal level is 100 and the headroom is zero, but now you get to see where you are to get a sense of your signal level reading and how much stronger or weaker pickups move the needles; the goal being to keep the range smack in the middle. BOSS is already keen on keeping default settings in the middle / high noon setting...and so am I !

When I get a chance to upload the patch, I will. I haven't even installed drivers yet.

EDIT 5/7/2012

Sorry it has taken so long for me to upload this patch. Just plug your guitar in and call up this patch on your GT-100. "Go to FV to Calib" is the name of this patch. This name also instructs you to go into your FX chain to the Foot Volume effect (located at the beginning of the chain) because there you will find the Vol Min and Vol Max parameters that are useful in measuring how strong or how weak your guitar is hitting the GT.

Your input calibration goal is to align your strongest playing intensity with the brief flashing of the EXP SW On/Off (red LED) near the physical EXP pedal. There is no need to hear the calibration patch so I have silenced it (FV @ 0). Done correctly, your normal playing intensity (or average playing intensity) will move the "needles" about the midpoint (50 on the dials).

Note the GT-100 has a global Input Sensitivity parameter (SYSTEM/INPUT menu) . Think of it as a "signal gate". It is the parameter you should adjust to boost or trim your guitars output level to align it to how the GT "senses" your guitar's output level. Also note that it is critical to leave the "tab 9", Assign Common, input sensitivity parameter set to 50, so don't change this setting or the whole calibration routine becomes pointless. After calibration though, you can change this as you like for your patches to skew the behavior of the global input sensitivity parameter, making your GT more or less sensitive, on a patch by patch basis.

The key benefits of doing this are as follows:
Your guitar will be optimized for the preamps. You will no longer get overdrive or distortion on the clean preamps when they are set at the default drive of 50.
You will get less noise from the higher gain preamps and OD/DS.
Your GT will be more responsive and optimized for control assignments that use Input Level source controller.

http://www.mediafire.com/?gdwvdl751y7hnex

[mmm]

this is all great ricig. Having read books like "The Mix Engineers Handbook", I feel that i usually have a pretty good understanding of this type of stuff ...

.... but I'm finding that I need to re-read some of this a few times. LOL.

Now, lets say I do this calibration with my loudest pickup ... (probably will end up being the passive EMG-HZ in my #3 guitar), but my #1 is a strat with Dimarzio virtual vintage pup's that have a similar output to vintage single coils (IOW, very low output). Would it be good to place something at the beginning of the chain, such as an EQ block set flat, that boosts the input? I will most likely have specific patches for each guitar, that way I can (hopefully) minimize the change in apparent volume between guitars and also make sure that I'm hitting the inputs of each stage of the signal chain at a good level. I'm guessing that if I put that boosted EQ block at the beginning of the chain (before the FV that you mentioned in your last post) that I'd be able to calibrate the level of boost needed.

Am I missing something? Does this sound like a good plan of attack?

[Ricig]

LOL

Unlike the GT-10, the GT-100 has no feature to save a setting for each guitar...bummer. For this case I would just make note of the calibrated setting for each of your guitars and then make the change when you change guitars. It'd take all of two seconds. You don't want to waste an EQ just to level balance your guitars...IMO.