Fletcher Munson curve effect on amp modeling

1poorplayer

Power User
I was wondering what fractal's approach to the Fletcher-Munson curve is , when it comes to amp modeling ?
I think this phenomenon of human hearing has played a hand , partially , in my dislike of most amp modeling devices over the years.
What I mean is , are the amp and cabinet sounds designed to sound great at high volume or low volume ?
 
They are, as you say 'models' so the tonestack and additional EQ is there in the amp block and other parameters in the Cab block for you to adjust to taste.

All sound producing devices (including the original amps that are modelled) are affected by the Fletcher-Munson curve - that's partly why they have Bass, Middle, Treble, Presence etc controls.
 
What you are describing is a function of human hearing, perception and the ears / brain.

But all is not lost, the Fractal comes with a volume control. Problem solved.
 
There are no real workarounds for F-M. If you want your presets to sound good at gig volume, dial 'em in at gig volume.
Best advice. Set it like you use it, with the band if at all possible. With the band and the FOH/monitor rig is even better.
 
I hear you guys. I'm not trying to stir up any trouble. I'm thinking there must have been an intended optimum volume through a full range speaker , when these replications were developed.
It's not a huge deal , but it IS relative to the overall tonal image of the sims. The reason I'm asking , is because I'm in line to order an AX8 , once it becomes available to order. Since it has no headphone jack , (which is a good sign ) I would guess it was designed to sound best at loudspeaker volume. The question would be , how loud ?
 
They are, as you say 'models' so the tonestack and additional EQ is there in the amp block and other parameters in the Cab block for you to adjust to taste.

All sound producing devices (including the original amps that are modelled) are affected by the Fletcher-Munson curve - that's partly why they have Bass, Middle, Treble, Presence etc controls.

Agreed. My fingers are crossed that the basic standard amp controls will do just fine in dealing with F-M when i eventually get my AX8.
With my past experience with line6 units , amp controls didn't cut it. I couldn't help thinking their developers designed their pedals to sound good thru headphones. I never cared for their sounds , live , or in the studio.
 
there must have been an intended optimum volume through a full range speaker , when these replications were developed.

the replications were made to be just like the real things, and those don't have an optimum full-range speaker volume.

if you turn up, there will be more bass and treble to your ears. that's all there is to it, no optimum. rooms and speakers used also make a difference, of course.

create your tones at (or as close to) the volume you'll perform and everything will be right.
 
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the replications were made to be just like the real things, and those don't have an optimum full-range speaker volumes.

if you turn up, there will be more bass and treble. that's all there is to it, no optimum. rooms and speakers used also make a difference, of course.

create your tones at (or as close to) the volume you'll perform and everything will be right.

Got it. Thanks !
 
FM affects any sound source, its about volume and perception, not about what is being heard.

Exactly. If you play thru a modeler , thru a FOH system, at a live band volume - VS playing an amp modeler thru headphones in a bedroom ..... it will sound different.

Whether it will require an EQ change in order to compensate for the FM effect...... during bedroom/headphone listening -OR- during FOH/loudspeaker listening ....... would depend on the volume and conditions the amp modeler was designed to sound best at , initially.
That's all I asked.
Maybe I should have said , "Does anyone know what dB spl Fractal uses when making amp presets ?"
 
I make all mine at 83db A weighted. I mix at that reference too.

I use a high passed pink noise wav file I got from Bob Katz's site to calibrate reference level.
 
I build / tweak patches in my home studio via reference monitors. Part of the challenge is getting the sound of the patches to still sound amazing in the context of a full band mix. I recommend you start with a big, full, awesome sound, but take a studio engineering approach when incorporating your sounds into the mix. During tech rehearsals I have my laptop running Axe-Edit, and make adjustments to my patches as we run through the material. I almost always CUT frequencies rather than boosting them. At home, I can make my tones sound amazing and huge in isolation, but when you add the rest of the band (keys, bass, drums, sax, backup vocals), there is often overcrowding in parts of the frequency spectrum. To open up space, I work with the keyboard player and bass player to apply complimentary EQ / shelving filters to our patches. The result is that our individual tones aren't as monstrously huge by themselves, but that's the point :) This really helps things sound better together, and gives the instruments a voice in the mix.
 
I build / tweak patches in my home studio via reference monitors. Part of the challenge is getting the sound of the patches to still sound amazing in the context of a full band mix. I recommend you start with a big, full, awesome sound, but take a studio engineering approach when incorporating your sounds into the mix. During tech rehearsals I have my laptop running Axe-Edit, and make adjustments to my patches as we run through the material. I almost always CUT frequencies rather than boosting them. At home, I can make my tones sound amazing and huge in isolation, but when you add the rest of the band (keys, bass, drums, sax, backup vocals), there is often overcrowding in parts of the frequency spectrum. To open up space, I work with the keyboard player and bass player to apply complimentary EQ / shelving filters to our patches. The result is that our individual tones aren't as monstrously huge by themselves, but that's the point :) This really helps things sound better together, and gives the instruments a voice in the mix.

This is one of the reasons I find the single amp approach ; found in the AX8 , appealing. There is a group of Helix supporters that are complaining about the AX8 for the very same reason.

I support your way of thinking.
 
Whether it will require an EQ change in order to compensate for the FM effect...... during bedroom/headphone listening -OR- during FOH/loudspeaker listening ....... would depend on the volume and conditions the amp modeler was designed to sound best at , initially.

i disagree as far as the amp models themselves.

if you are asking about the Factory Presets, that is a completely different thing, as they may have been created/adjusted at a particular volume.

but the amp models themselves most likely have no "ideal" volume since they are modeled after the physical versions which are prone to the FM curve just as much as a modeler.
 
i disagree as far as the amp models themselves.

if you are asking about the Factory Presets, that is a completely different thing, as they may have been created/adjusted at a particular volume.

but the amp models themselves most likely have no "ideal" volume since they are modeled after the physical versions which are prone to the FM curve just as much as a modeler.

I would agree to disagree.
Someone MUST make the decision on which IR used to "match" with each amp being modeled. Pretty tough to make that decision without listening.
How loud the example is during the .....listening , would affect the decision , - due to the FM effect.
 
I support your way of thinking.
Thank you :)
I am reductionist in my approach to all things musical.

When I'm recording, I capture a lot more than I need. I record multiple takes and tracks of guitar / bass / drums / percussion / vocal / keys parts, and keep everything from the sessions. Then when engineering / mixing, I audition the tracks to identify those that work well together to form a solid rendition of the song, then begin to dissect each track to find its most important elements. My general rule for this is asking myself "what's the cool thing here?", and then I mute the stuff around it, just keeping the element that makes that part special. I do this across all of the tracks, and open up space in the song. As I mix down and add effects, I continue to remove content to give the effects some room to speak. If necessary, I'll reintroduce previously-muted track material or record additional content based on the shape the song is taking. My goal is to do what's best for the song, and avoid overstuffing the mix. I sometimes go back and re-record my takes based on the chopped up / reduced version that I've arrived at during mixing.

I do this with dynamics and spatial positioning as well. I want the music to breathe. When I hear something with excessive density, where every sixteenth note has something happening, the frequency spectrum is overloaded, and the entire mix is compressed / boosted to 0 dB, it just doesn't have any emotion to me. There are times when that high-density feel is very useful, such as when you want to create a sense of tension / energy, or for dance mixes. But without contrast or variation, music doesn't resonate with me.
 
Maybe I should have said , "Does anyone know what dB spl Fractal uses when making amp presets ?"
They don't. Before you shrug off my answer, bear me out...
  • Volume doesn't matter with amp sims. The models are designed to replicate the real thing so for any given setting, the output waveform is the same for any given input waveform. Volume is just the amplitude of the wave form but there's no timbral difference associated with it.
  • Volume doesn't matter with cab sims. Cabs themselves are pretty much linear in response until you get to the breaking point. Don't bother arguing with me. If you must, go to TGP to have that discussion with Jay Mitchell. :) So the volume at which the IR is captured affects S/N ratio more than timbre.
So if the amp model is independent of volume and the IR capture is independent of volume, there's not much in a modeled rig that's dependent on the volume at which Cliff and company worked.
 
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