AxeFx3 and FM3 JP2C question

Snouttrout

Inspired
I recently bought the real JP-2C amp and I wanted ask a few questions about the modeled amp on the AxeFx3/FM3.

Last night with my band, I used the following settings on the real JP2C through a Mesa 2x12 cab. Note that presence is pulled and shred mode is off on the real amp. I found that these settings worked incredibly well, and the amp had virtually no hiss, even with the master set this loud. I've never had an amp that sounded so amazing. Please see preamp and 5 band eq settings attached. I found that the low end was very focused and tight. I didn't need any kind of pre-amp boost or cut that is available in the AxeFx. The shred mode mode sounded too harsh so I turned it off; it sounded great without it.

I also a have a patch that I made with some IRs on the AxeFx with the settings attached in the pic. I tried using those same settings through my Matrix GT1000Fx with the real 2x12 Mesa boogie cab (note that the IRs are bypassed for the test). I noticed that without the cut or preamp boost engaged, the AxeFx sounded really boomy through the cabs, unless I use those cuts or boosts like I've been using for the IRs. When I made this patch, I used the input boost because it sounded too boomy through the IRs as well with these settings.

I'd like to use the AxeFx in the same way that I'm using the real amp--without boosts--because I like how it feels and sounds. Apart from having the high treble set to 3.58 to mimic the shred mode (which I'm not using on the real amp), do you think I'm getting the boominess from the Axefx from the preamp or the 5 band eq on the AxeFx? Note that I'm trying to turn the input boost off because I don't need it with the real amp and cab.

By the way, the JP2C green channel is spot on perfect. I've been using it without the 5 band EQ. So I think the boominess on the yellow channel might be the output EQ. Any tips or comments for how to adjust my AxeFx settings without using cuts or boosts in the preamp so make it sound like my real JP2C? It's really hard to compare the output EQs.





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You can’t map the physical settings on the real amp the the Axe model and expect the same results. There are all sorts of taper and tolerances that will cause the analog circuitry to differ from the digital version. This seems to me like it’s just a matter of tweaking. Use your ears, not your eyes.

am I misunderstanding your concern?
 
I believe the taper on the 5-band sliders on the Axe is different than on the real amps. The real amps have some parts of the EQ slider with little effect then others with lots of effect. I believe Cliff changed it so you'd get more audible effect the entire way along the travel. But this also means the visual shape won't match. you might be getting more bass than you think at those slider settings.

Another thing is that your Input drive is low compared to the real amp. I think internally the input drive is mapped to 7, or 8 if pulled on the Yellow channel, and 8 or 9 if pulled on the red channel
 
In the amp block, go to the "Speaker" tab. There are parameters there that adjust the high/low resonances that occur due to the interaction between the virtual power amp and speakers. When using a real power amp and cab you may want to set the speaker impedance curve to "Resistive Load" or lower the "LF Resonance" and "HF Resonance" so you're not doubling up on these resonances. Otherwise you may get boomy lows or strident highs. This is mostly applicable when using a real tube power amp, but if the Matrix is voiced to sound like a tube power amp it may help in your case too.
 
You can’t map the physical settings on the real amp the the Axe model and expect the same results. There are all sorts of taper and tolerances that will cause the analog circuitry to differ from the digital version. This seems to me like it’s just a matter of tweaking. Use your ears, not your eyes.

am I misunderstanding your concern?
[/QUO
I believe the taper on the 5-band sliders on the Axe is different than on the real amps. The real amps have some parts of the EQ slider with little effect then others with lots of effect. I believe Cliff changed it so you'd get more audible effect the entire way along the travel. But this also means the visual shape won't match. you might be getting more bass than you think at those slider settings.

Another thing is that your Input drive is low compared to the real amp. I think internally the input drive is mapped to 7, or 8 if pulled on the Yellow channel, and 8 or 9 if pulled on the red channel

If I use the Axefx with input boost turned off, I do increase the gain to compensate. But the bottom end is still too boomy. I didn't realize that the 5-band EQs were different on the AxeFx...I thought those were authentic. But perhaps there are differences among the different amps.
 
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In the amp block, go to the "Speaker" tab. There are parameters there that adjust the high/low resonances that occur due to the interaction between the virtual power amp and speakers. When using a real power amp and cab you may want to set the speaker impedance curve to "Resistive Load" or lower the "LF Resonance" and "HF Resonance" so you're not doubling up on these resonances. Otherwise you may get boomy lows or strident highs. This is mostly applicable when using a real tube power amp, but if the Matrix is voiced to sound like a tube power amp it may help in your case too.

I didn't know about this, but note that I get the boomy sound on the IR and the real cab when using the AxeFx model. Maybe all I need to do is experiment with the 80 Hz slider.
 
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I didn't know about this, but note that I get the boomy sound on the IR as well as the real when using the AxeFx model. Maybe all I need to do is experiment with the 80 Hz slider.
You may also want to play with the master volume because it's one of the few controls where the taper of the virtual knob may differ greatly from the real amp. Pushing the power section more or less than you were on the real amp could explain some of the EQ differences you're hearing.
 
You may also want to play with the master volume because it's one of the few controls where the taper of the virtual knob may differ greatly from the real amp. Pushing the power section more or less than you were on the real amp could explain some of the EQ differences you're hearing.
Thanks for the reply. On the real amp, there is a certainly a level to where there is noticeable difference in sound, which occurs at about 4/10. I found that the real amp seems to just get louder at about 6/10, but it sounded very similar to 4/10. But that is something I will experiment with.
 
I believe the taper on the 5-band sliders on the Axe is different than on the real amps. The real amps have some parts of the EQ slider with little effect then others with lots of effect. I believe Cliff changed it so you'd get more audible effect the entire way along the travel. But this also means the visual shape won't match. you might be getting more bass than you think at those slider settings.

Another thing is that your Input drive is low compared to the real amp. I think internally the input drive is mapped to 7, or 8 if pulled on the Yellow channel, and 8 or 9 if pulled on the red channel
I meant to respond to this suggestion:

If I use the Axefx with input boost turned off, I do increase the gain to compensate. But the bottom end is still too boomy. I didn't realize that the 5-band EQs were different on the AxeFx...I thought those were authentic. But perhaps there are differences among the different amps.[/QUOTE]
 
I meant to respond to this suggestion:

If I use the Axefx with input boost turned off, I do increase the gain to compensate. But the bottom end is still too boomy. I didn't realize that the 5-band EQs were different on the AxeFx...I thought those were authentic. But perhaps there are differences among the different amps.
[/QUOTE]
Different taper =/= inauthentic. As you noted, two amps may have sliders with different tapers. Such inconsistencies don’t exist in the digital realm. As was also noted, the master volume in the Axe is a known control with a modified taper vs analog amps. Cliff did this to provide a more usable range on that control.
 
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