Understanding All the Different Gain Controls

Hi all. I have a question. What parameter should I have to change to compesate a single pickup guitar and a humbucker? I mean, using an Strat in a preset and a Les Paul in another preset and both having the same output level?
 
Hi all. I have a question. What parameter should I have to change to compesate a single pickup guitar and a humbucker? I mean, using an Strat in a preset and a Les Paul in another preset and both having the same output level?
I’d go for Input Gain (Setup -> I/O -> Input page), its global so you won't have to mess with every preset. If you want per preset, just do it using the "Output Level" in the Input block. Alternatively, if you want it to be switchable, you can do it using the Input Boost in the Amp block (use the Neutral Boost Type), or just push the gain knob. Many ways to skin this cat.
 
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I didn't see it mentioned-but I didn't read everything here either.
But it's worth mentioning that as you turn up the input drive the cap across it looses its effectiveness. For example if you have a Plexi and run it full up a-la Van Halen that cap is basically not doing anything.
But if you have it turned way down it makes the amp quite bright sounding.
 
Hi all. I have a question. What parameter should I have to change to compesate a single pickup guitar and a humbucker? I mean, using an Strat in a preset and a Les Paul in another preset and both having the same output level?
I agree with @Shahar, but just increasing the level to match isn't going to make a single coil sound like a humbucker. Not sure if that's what you're asking?
 
I didn't see it mentioned-but I didn't read everything here either.
But it's worth mentioning that as you turn up the input drive the cap across it looses its effectiveness. For example if you have a Plexi and run it full up a-la Van Halen that cap is basically not doing anything.
But if you have it turned way down it makes the amp quite bright sounding.
It's literally in the first post :D

Input Drive:
This is the modeled amp's gain, drive, volume, etc. control. It adjusts the attenuation at the input to the amplifier gain stages after the input buffer. On a Marshall Plexi, for example it is the "Loudness" control. On a typical Fender amp it is the "Volume" control. On many high-gain amps it is called either "Gain" or "Drive".

On a real amp this is implemented using a variable resistor called a potentiometer. Many amps include a "bright cap" on the drive control which is a small value capacitor placed across the terminals of the pot that bleeds treble frequencies through as the gain is reduced. Sometimes this bright cap is switchable via a switch on the amp. Sometimes it is fixed.
 
Hi all. I have a question. What parameter should I have to change to compesate a single pickup guitar and a humbucker? I mean, using an Strat in a preset and a Les Paul in another preset and both having the same output level?
A lot of guys use a Filter block with the 'Null' type and adjust the level to change the preset output level with a footswitch. You can also tweak the Input Trim in the Amp Block's Ideal page to compensate as well.
 
Dear Cliff

Much thanks for explaining the basic gain control paradigm of guitar amps to all axefx users. I think this will help most people to understand all these different controls and their relationship to each others a lot better. Even there is a slight difference from your explanation of the controls and your basic paradigm drawing, which made me quickly put together another drawing (handpainted, because I'm really suck on computer equipment when it comes to drawings.....took me hours to get the stuff right....uugh!)

afparadigm.jpg


Explaning input trim:

Input trim as it's inside your axefx is something you normally don't have on your amp, because you're not only able to attenuate the signal, you can also boost it! So therefore is the buffer amp shown in cliffs paradigm diagram, now shown as controllable input buffer in my drawing. The input drive on all amps is located behind the first gain stage - on all guitar amps.

Explaning Mastervolume Trim (MV-Trim):

Mastervolume Trim is something which you wouldn't find in a real amp too.
(There are possibilities to change the phase splitter design when in- or decreasing the tail resistor in the long pair tail splitter design which results in sending more or less signal from the phase splitter to the input grids of the power tubes.....but you won't find this as a dedicated control inside an amp)

It in- or decreases the signal coming to the power amp section, it's not a fine tuning master volume control or even a multiplier for the master volume....

Hint: The Master volume position can be altered in the advanced parameters (MV location). In the drawing it's PRE-PI (before the phase splitter also can moved after the phase splitter which is called PPIMV or Post-PI, see Axe-Wiki or your AxeFx User manual)

MV Cap: Same as the bright switch - but over the Master volume potentiometer - shown here as a switch, in the axefx you can control the capacity of capacitor in picofarads (which is value multiply 10^-12 ) with MV Cap . This does the same as the bright cap, on lower master volume settings. This unique master volume bright cap feature is often seen in Dumble type of amps.


Cheers
Paco(sipulami)
This drawing no longer shows up. Anyone have a copy?
 
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