In a typical preamp with 4 stages (eg Fender/Boogie), the Tone Stack is between the second and third stages. The tone stack reduces the already boosted signal amplitude significantly so the stages following boost the signal back up and then drive the output to the power amp.
In a typical preamp with 4 stages (eg Fender/Boogie), the Tone Stack is between the second and third stages. The tone stack reduces the already boosted signal amplitude significantly so the stages following boost the signal back up and then drive the output to the power amp.
Many thanks !
I've read Page 172 of the manual:-
" ..... An additional setting can be found on the last page of the amplifier module: A soft button allows you to set the
position of the equalizer to either “Post” (after) or “Pre” (before) the amp module. The EQ has a different impact on
the sound of a distorting amp, depending on its position. In tube amps, it is positioned between the preamp and the
power amp. Most modern guitar amps with a master volume control perform the distortion in the preamp; thus, the
equalizer is positioned after the distorting circuit. Classic amps without master volume control (such as Vox® AC-30),
produce the distortion in their power amp. In this case, the equalizer is positioned before the distorting circuit.
However, setting the position according to the original amp is not mandatory, since the authentic sound of the
reference amp has already been captured, and therefore includes the original equalizer setting ..... "
The bit I cant seem to get my head around, is now that we have a Modeled Gain and Modeled EQ plus the Actual Profile ..... which part of what gets put where when selecting EQ "pre" or EQ "post " (?)
Ben
The gain hasn’t really changed. It isn’t “modelled” as such. The profiling noises might have been adapted a little (or maybe not I don’t have any inside information on that sort of stuff) but the main difference is that it is now recommended to profile on max gain in order to capture the full range of the amp during the profiling process.
I am fairly sure the EQ part is the genius bit that has taken so long to figure out. If the EQ is before the clipping gain stages (like a Boogie or Fender) then it has a dramatic effect on the character of the distortion not just the frequency output. However, if it is placed after the distortion gain stages (like a Marshall or EVH etc) then it has much less effect on the character of the distortion. Being able to model not just the EQ curve but also how it influences any overdrive that follows it is a pretty big leap for profiling which is probably why none of the other capture technology (NAM, ToneX, Quad Cortex) offer it.
So in simple terms. If EQ is Pre then it behaves like a Fender/Boogie and affects the type of distortion created . If it is Post then is has little or no effect on the distortion character but shapes the tone of the existing distortion.
The gain hasn’t really changed. It isn’t “modelled” as such. The profiling noises might have been adapted a little (or maybe not I don’t have any inside information on that sort of stuff) but the main difference is that it is now recommended to profile on max gain in order to capture the full range of the amp during the profiling process.
I am fairly sure the EQ part is the genius bit that has taken so long to figure out. If the EQ is before the clipping gain stages (like a Boogie or Fender) then it has a dramatic effect on the character of the distortion not just the frequency output. However, if it is placed after the distortion gain stages (like a Marshall or EVH etc) then it has much less effect on the character of the distortion. Being able to model not just the EQ curve but also how it influences any overdrive that follows it is a pretty big leap for profiling which is probably why none of the other capture technology (NAM, ToneX, Quad Cortex) offer it.
So in simple terms. If EQ is Pre then it behaves like a Fender/Boogie and affects the type of distortion created . If it is Post then is has little or no effect on the distortion character but shapes the tone of the existing distortion.
Huge thanks Alan !
Just as a side note re: the Gain Stack ... I have no inside knowledge ..... but C.K has repeatedly said that the Gain Stack and EQ Stack of the "Amp Channel" Amps have (?) both been modeled ...... whatever he's done, its amazing 
The other thing that caught my eye .... Many years ago I was running a KPA using FW 3.x or 4.0x before I left the platform .... and I distinctly seem to remember that the FW .bin files were always around 3.5mb in size .... when I got my stage and loaded OS 10 I was struck [unexpectedly] that the FW size is now something like 6 x that size .... lots of new "bits" pardon the pun
All the best and thanks again.
Ben
