Tips on how to tame upper midrange harshness live

outloaf

Member
Hey guys, so I've been having an issue with upper mids when it comes to live, DI sounds great with cab Sims and whatnot. I'm not running FRFR full time yet because I need the live Mesa 412 weight behind me for certain projects. Now, I've done extensive tests by using the ax8 as a preamp into the fx loops of the real-world counterparts, ss power amps with the power amp modeling on and basically every possible combination of set-up possible. I should also add that I've had a few international album, toured the world, recording in some of the world's most gorgeous studios and have owned plenty of lovely amps and run my own studio. Unless I'm missing something; I have found that for whatever reason the ax8 has an overabundance of 1.7k-3k, 200-300hz and is devold of around 60hz compared to all of the real world versions of the models. Thus ranges from anow ac15 to a rectifier. To a mark 4 to a 5150 block letter and 6505+ when not going FRFR. I've even A/B'd just the preamp of every amp I could to the preamps of the ax8 and found the same "issue." If anyone has any insight on how to correct this without using additional eq, please chime in. Also, it's not a matter of the unit not sounding good, because it's amazing and the feel is dead on, if not more responsive than the actual amps and with enough eq trickery I can get it to sound basically dead-on.. it's mainly just a matter of dialing in something from scratch and not being able to trust that the ax8 model is truly sounding like what it is modeling out of the box. Thanks again.
 
Check your global EQ. Something isn't right. The frequency response of the preamp and power amp modeling is spot-on.
 
Global EQ is off.. I've reset, updated to latest firmware, used different XLR and 1/4 in cables, guitars, cabs.. Everything.. I have no doubt that the frequency response is supposed to be spot-on because the pick attack, harmonic content and even the finite detail of the presense control on the 5150 model is dead on.. its just the overall spectral balance is off. The only way that I can get it to sound dead-on is by adding 5db at 63, subtracting 3 at 250 and a decently wide 4db cut around 2200.
 
Global EQ is off.. I've reset, updated to latest firmware, used different XLR and 1/4 in cables, guitars, cabs.. Everything.. I have no doubt that the frequency response is supposed to be spot-on because the pick attack, harmonic content and even the finite detail of the presense control on the 5150 model is dead on.. its just the overall spectral balance is off.

I don't know what "spectral balance" means. We compare the frequency response of the model (both with and without the power amp modeling) to the actual amps using a dual-channel FFT analyzer. The models are spot-on. Frequency response IS a "spectrum".
 
Sorry, yes the spectrum.. Being an audio engineer we use the term "spectral balance", my apologies... But yes, this is definitely intriguing because I know that you guys obsess over nailing every detail of the real-world amps. When loading up a fully reset amp simulator; that is supposed to be the same as how the real world amp would be with roughly the same settings without having to dig into the advanced menu settings and speaker resonance?
 
What are you using to view the output spectrum? Are you building patches with just the amp block for testing? Is your input pad set correctly? Are you using the proper output setting (-10db/-4db) for the device getting the ouptut.

These are not Amp simulators, or tone matchers. They are circuit component emulators, simulating blocks of circuits. They are tools and adaptive to many inputs and outputs, so must be setup for each integration into a rig, to take full advatage of the design. The default output setup for factory patches, is for FRFR. So building custom patches for your rig is key. There are also tricks to use to get a more realistic amp tone when using just the preamp sim, or a FRFR setup, and that's using various blocks to cut below ~100-150hz and above ~6k-8khz.

But my unit most certainly does not a have a mid spike at all, obvious to me since I have to boost those areas to get that particular tone. But I am running it into studio monitors.
 
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Global EQ is off.. I've reset, updated to latest firmware, used different XLR and 1/4 in cables, guitars, cabs.. Everything.. I have no doubt that the frequency response is supposed to be spot-on because the pick attack, harmonic content and even the finite detail of the presense control on the 5150 model is dead on.. its just the overall spectral balance is off. The only way that I can get it to sound dead-on is by adding 5db at 63, subtracting 3 at 250 and a decently wide 4db cut around 2200.

Interesting. I routinely cut a few db at 250 using GEQ in the Amp block and cut the 2-3k range using Character control too.

The Character parameter is the most powerful I've discovered in there so far. It's not the same as cutting with EQ, though I don't know why.
 
I have played with running straight into a Stealth ISP poweramp and 412 cabinet. I have noticed a slight eq adjustment is needed. I will try the values listed above and see if I find the same. I did try a GEQ with a cut around 4-8k which helped ballpark the comparison.
 
But isn't he running through a mic'd cab and FRFR from the fractal using the IR from the cab?

The real amp is amp->speaker->microphone. The Axe-Fx is using the IR obtained from that speaker and mic. It's as apples-to-apples as possible.
 
I thought the question was running an amp into a cabinet compared to running the AX8 into a SS power amp into a cabinet..... at least that's what I was talking about and thought the OP was in that direction. I have run an amp into a 2 notes using the same IR and have no issues whatsoever with that comparison. I setup a Fuchs FH50 amp and used the Fuchs ODS in my AX8. I ran the same amp into a 412 Orange cab with V30's, but when running my AX8 into the stealth and then into the Orange there is a slight difference. Minor eq and done. I was curious on the thoughts for that point.
 
I thought the question was running an amp into a cabinet compared to running the AX8 into a SS power amp into a cabinet..... at least that's what I was talking about and thought the OP was in that direction. I have run an amp into a 2 notes using the same IR and have no issues whatsoever with that comparison. I setup a Fuchs FH50 amp and used the Fuchs ODS in my AX8. I ran the same amp into a 412 Orange cab with V30's, but when running my AX8 into the stealth and then into the Orange there is a slight difference. Minor eq and done. I was curious on the thoughts for that point.

If you think about it a while you'll see why it's the same thing. (Hint: replace "SS power amp into cabinet" with IR).
 
I understand that theoretically it would be.... However, standing in front of the cab there is a minor eq difference in the higher frequencies. Slight.
 
I understand that theoretically it would be.... However, standing in front of the cab there is a minor eq difference in the higher frequencies. Slight.

Then the SS power amp is not flat. Those cheap power amps like that aren't known for their accuracy.
 
Fair enough.
I'm just glad to get as close as it does. I've been using something else for over 4 years and the speaker was not fully separate so it never really got "there". I just wish I had a deeper understanding of the AX8 parameters within the amp (deep parameters) to know what variable changes have specific influences on tonal changes i.e. (what does what and why). With that knowledge and a Dr Pepper I might be borderline dangerous.
 
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