Legacy Amp models consider revisiting? Full honest request and opinion

[FractalAudio]

I think I need I tee shirt with "Toobz rule brah." on it.

 

[SoZo]

Depending upon the amp the low frequency response can be highly dependent upon the load. So selecting the right Speaker Impedance Curve becomes important.

Dynamic Depth is a non-physical tweak. It uses what I call "Inverse Homomorphic Processing". Anything other than zero is deviating from authentic. It's not wrong to use it but it will be less accurate.

The power amp modeling IS current modeling. Power tubes are essentially current sources (with some finite resistance in parallel). Dynamic Depth has nothing to do with this.

The other big thing is Master Volume. As you raise the MV the power tubes will saturate on the lows and highs first which causes the tone to have more midrange and vice-versa.

Most of the controls in the Axe-Fx match their physical counterparts. The exceptions are Presence and Master Volume. Most amps simply have the wrong taper for their Presence controls. For example a 5150 Presence control does absolutely nothing from 0 to 7. All the action happens in the upper 1/4 of the control's range which is just dumb. The Axe-Fx uses a proper taper which gives a nice, even response over the full range of the control.

Likewise the Master Volume on many amps is too abrupt. By 2-3 on the knob the power amp is saturating. Again we use a more rational taper so that you have finer control over power amp distortion.

The downside of this approach is that if you put the Presence and Master Volume controls in the same position as the amp it won't sound the same. People do this then post videos and proclaim "See? Modeling isn't accurate!!! Toobz rule brah."

Yup fully understand its due to the audio taper potentiometer... The difficulty I guess I and several (3) others I know with the ax are having after YEARS of using amps the proven format is not immediately transferable. The new format is now based only on the fractal ... So there is a learning curve I guess.
Thanks for the explanation ....

John

 

[Liam Thompson]

I don't... Care to enlighten the masses?

I'm going to take a guess at John Gaynor of SoZo Capacitors?

 

[Bruce Sokolovic]

Depending upon the amp the low frequency response can be highly dependent upon the load. So selecting the right Speaker Impedance Curve becomes important.

Dynamic Depth is a non-physical tweak. It uses what I call "Inverse Homomorphic Processing". Anything other than zero is deviating from authentic. It's not wrong to use it but it will be less accurate.

The power amp modeling IS current modeling. Power tubes are essentially current sources (with some finite resistance in parallel). Dynamic Depth has nothing to do with this.

The other big thing is Master Volume. As you raise the MV the power tubes will saturate on the lows and highs first which causes the tone to have more midrange and vice-versa.

Most of the controls in the Axe-Fx match their physical counterparts. The exceptions are Presence and Master Volume. Most amps simply have the wrong taper for their Presence controls. For example a 5150 Presence control does absolutely nothing from 0 to 7. All the action happens in the upper 1/4 of the control's range which is just dumb. The Axe-Fx uses a proper taper which gives a nice, even response over the full range of the control.

Likewise the Master Volume on many amps is too abrupt. By 2-3 on the knob the power amp is saturating. Again we use a more rational taper so that you have finer control over power amp distortion.

The downside of this approach is that if you put the Presence and Master Volume controls in the same position as the amp it won't sound the same. People do this then post videos and proclaim "See? Modeling isn't accurate!!! Toobz rule brah."

Interesting. I’ve been using my boogie mark V lately and I’m certain some of the presence and treble knobs do nothing for a large part of their sweep.