Another trick...High Pass / Low Pass

jzucker

Experienced
I'm sure most of you veterans already know this. I have periodically experimented with the cutoff frequencies on overdriven tones...Mostly for getting the characteristic Allen Holdsworth violin tone. I'll typically set the high frequencies to cut off at on or just under 3k. However, the other day, I noticed on my strat I noticed that the clean and semi-clean tones were just super zingy and the bridge pickup was ice-picky. So, I set the high freq cutoff to 4k.

WHAT A DIFFERENCE!!!


In retrospect, I think the axefx architecture tends to add some low end and high end that is not present in the real amps and setting these cutoffs properly is essential to getting a more realistic sound.
 
In retrospect, I think the axefx architecture tends to add some low end and high end that is not present in the real amps and setting these cutoffs properly is essential to getting a more realistic sound.

The frequency response is identical to the actual amps modeled. That is part of the modeling process. The models are EQ matched to the amps and the data stored in the firmware.
 
The frequency response is identical to the actual amps modeled. That is part of the modeling process. The models are EQ matched to the amps and the data stored in the firmware.

I don't care if they are frequency matched or not. I get high frequencies out of the output that just aren't there in a real amplifier. A guitar speaker typically cuts off sharply at between 4k and 5k. There's no need to have frequencies above that unless you are driving it with a bass (slapping) or acoustic guitar. The fractal amps tend to have more low end and more high end than the real thing. Whether this is imparted by the various components along the block chain or the amp itself is irrelevant.

So I limit the high frequencies in the cabinet itself. Also, many of the 3rd party speaker solutions that are supposedly flat response are really not flat. You will often get HUGE amounts of bass frequencies at louder volumes due to cabinet design and fletcher-munson curves. Many folks don't care about this because a huge part of the fractal audience is playing metal or djent where the extra bottom end enhances the guitar sound but if you are playing jazz or clean tones or fusion tones, the extra bass and high frequencies sound unnatural IMO.
 
The fractal amps tend to have more low end and more high end than the real thing.

No they don't. That's the whole point of matching. Even without matching the modeling is so accurate now that any deviations are less than 1 dB.

You can't compare what you are used to hearing "in the room". The close-mic'd sound ALWAYS has more highs and lows. This is due to the physics of near-field micing. And this is why a highpass and lowpass are frequently employed at mixdown.
 
No they don't. That's the whole point of matching. Even without matching the modeling is so accurate now that any deviations are less than 1 dB.

You can't compare what you are used to hearing "in the room". The close-mic'd sound ALWAYS has more highs and lows. This is due to the physics of near-field micing.

That's the whole point. What I want to hear is what the amp sounds like when listening to it or how it sounds after having been mixed on record. I don't want it to sound like it still needs mixing and eq'ing after the fact. If you're using it for recording you can tweak it to your liking but I'm talking about using it live to sound like an amp in the room. This is one reason why some folks think the kemper sounds more realistic. It doesn't in reality but it's eq'd on output a bit different so it sounds warmer and with less boomyness.

Some future version of axefx should have a global eq button that can apply the types of settings i'm talking about.
 
I don't care if they are frequency matched or not. I get high frequencies out of the output that just aren't there in a real amplifier. A guitar speaker typically cuts off sharply at between 4k and 5k. There's no need to have frequencies above that unless you are driving it with a bass (slapping) or acoustic guitar. The fractal amps tend to have more low end and more high end than the real thing. Whether this is imparted by the various components along the block chain or the amp itself is irrelevant.

So I limit the high frequencies in the cabinet itself. Also, many of the 3rd party speaker solutions that are supposedly flat response are really not flat. You will often get HUGE amounts of bass frequencies at louder volumes due to cabinet design and fletcher-munson curves. Many folks don't care about this because a huge part of the fractal audience is playing metal or djent where the extra bottom end enhances the guitar sound but if you are playing jazz or clean tones or fusion tones, the extra bass and high frequencies sound unnatural IMO.

This is probably one of the biggest things that people forget about amp modelers. They are meant to reproduce the sound of a mic'd amp, not just the amp itself. So in order to do a true comparison you would have to mic up the real amp in the room as well, which is naturally going to change the sound of that amp.
 
This topic has been talked about at length for year on this forum. Axe sound like what a guitar sounds mic'd up through a PA. I for one never liked how my guitar sounded mic'd. It never sounded like it did in my room or practiced space. I changed that mentality when I joined FAS. I tweak with FOH in mind so my patches are mix ready. Lot's of guys say they don't care about the crowd but only care for themselves. I happen to love the results I get when I tweak accordingly
 
I think people try to compare the sound in front of the full box with the Axe-sound with an IR.

What I don´t understand - jzucker says, a guitarspeaker cuts ab 4-5khZ - but a close-miced amp produces higher frequences?

Would be cool to hear a comparison - I´v got no real amp.........
 
This topic has been talked about at length for year on this forum. Axe sound like what a guitar sounds mic'd up through a PA. I for one never liked how my guitar sounded mic'd.
Yup. The never ending story. Also, for the billionth time: you do not have to run an AFX FRFR. It sounds dead bang "amp in the room" with no f*cking around when going from power amp to cab because the mic is 100% gone from the equation, you are limited by your physical cab selection but it is no worse than traditional gear in that sense and it is totally worth it if AITR tone is your goal.

If you want to fight reality and try to AITR from FRFR you should be on your own, IMHO. AxeFx is all about accuracy, I don't want a jzucker curve on the device's output. You have more than enough frequency response control in the box to do this yourself.
 
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I have the feeling that some things are compared that shound not be compared.or actually SHOULD be compare. Not an expert, but this is how i always understood it:

AXE as pre amp
AXE FX (No cab block involved, no mic involved) Power Amp sag off
1. Axe FX with amp SAG off ( not sure if amp sim should be turnd off) and cab switched off (block not in shunt or cab sim off) should behave exaclty towards an PowerAmp and with a cab it should act exaclty as a comination of that particular setup. If you have it set up as a MesaPreAmp and you feed this into the input of the return to amp it should give same response and sound as you use same power amp and same cabinet (this is a non mic-ed solution). So they should have same sound if you have set everthing the correct way.

If you then put a mic on this cabinet and do a and b switching: (axe to real pre-amp) again you should hear same output again.

Then the comparison is correct (apples with apples)

2. Axe FX (no cab block or cab sim off) to non tube amplification and output to real cab 4x12
This should have an almost very near result as the real deal (not mic-ed) 4x12 sound and feel
this should deliver in the room sound as well
Not sure what exact result is, never tried and do not know what frfr color the frfr solid amp gives

3. AXE FX with cab & amp sim on and in the shunts activated
Here its very very important that you compare again the correct things.
As here the mic and the cab are very important
If you have a cab IR of the amp and mic 100% the same and isolated and done an utrares copy of this then if you give the result to a monitor or a DAW this should give an exact result as the same setup with a real amp, cab and mic towards the monitor or DAW.
Again apples with apples

4. the axe fx di methode (but im not familiar with that one) maybe someone can give this result.
And im sure there are some others.

bottomline: you can NOT compare and SHOULD not compare mic-ed AXE cab&mic output with non mic-ed in de room sound.

As soon as you use the cab block (with mic as cab IRs means a mic is used to reference the impact on frequencies) and have that in the routing towards the actual output used you can only really compare that sound IF: you have to have the SAME CAB and SAME Mic on the SAME position and prefferably done in a very good (studio) setup to avoid interferance of noise and reflactions)

And I really believe that the AXE FX is really really close on amp modling and that Cliff & FAS has done the matching of amps as good as he can get (almost exact behaviour of the real amp). The discussion on the in the room sound should not be connected nor compared to mic-ed sound.

thats my 2 cents
;)
 
I think people try to compare the sound in front of the full box with the Axe-sound with an IR.

What I don´t understand - jzucker says, a guitarspeaker cuts ab 4-5khZ - but a close-miced amp produces higher frequences?

Would be cool to hear a comparison - I´v got no real amp.........

A guitar speaker cuts at 5 kHz or so, depending on the type, and the sound is then absorbed by the room acoustics, surface etc. That's what your ears hear.

A mic close to the speaker captures the sound of the (same) speaker, which is very brittle, and adds mic coloring, which then is amplified through a FR system, which is typically closer to you than a guitar amp.

So the speaker is the same, but not the techniques.
 
I don't care if they are frequency matched or not. I get high frequencies out of the output that just aren't there in a real amplifier. A guitar speaker typically cuts off sharply at between 4k and 5k. There's no need to have frequencies above that unless you are driving it with a bass (slapping) or acoustic guitar. The fractal amps tend to have more low end and more high end than the real thing. Whether this is imparted by the various components along the block chain or the amp itself is irrelevant.

So I limit the high frequencies in the cabinet itself. Also, many of the 3rd party speaker solutions that are supposedly flat response are really not flat. You will often get HUGE amounts of bass frequencies at louder volumes due to cabinet design and fletcher-munson curves. Many folks don't care about this because a huge part of the fractal audience is playing metal or djent where the extra bottom end enhances the guitar sound but if you are playing jazz or clean tones or fusion tones, the extra bass and high frequencies sound unnatural IMO.
In what setup are you comparing the sound (i.e. saying real amps do not deliver these range of frequencies and the AXE FX does)? In both situations through a real cabinet, mic-ed or non mic-ed? Wondering what setup gives this difference in freq.
 
I'm sure most of you veterans already know this. I have periodically experimented with the cutoff frequencies on overdriven tones...Mostly for getting the characteristic Allen Holdsworth violin tone. I'll typically set the high frequencies to cut off at on or just under 3k. However, the other day, I noticed on my strat I noticed that the clean and semi-clean tones were just super zingy and the bridge pickup was ice-picky. So, I set the high freq cutoff to 4k.

WHAT A DIFFERENCE!!!


In retrospect, I think the axefx architecture tends to add some low end and high end that is not present in the real amps and setting these cutoffs properly is essential to getting a more realistic sound.

Hi Jack

How much time have you spent running the Axe through a good ss power amp and a real guitar cab that you are familiar with?
I think that after you've done some of that you'll come to realise that the hi-lo issues you're talking about are not issues with the Amp Block but rather with the Cab Block.
In particular, the Fender, and Mesa sims sound pretty much identical through my EV cabs as the real amps sounded.

The Cab Block, as it is designed now, can not duplicate the sound of a real cab in the room.
But what it can do is to pretty much perfectly match the tone that a recording engineer (or FOH guy) would see at his console when mic'ing a cab with a particular mic (or mics) at a particular mic position(s).
As you know, close mic'ing always involves extremes of top and/or bottom end in the signal.
Sometimes you can find a mic position that doesn't require any further EQ at the console but that's a rarity IME.
Most cab IR producers do not EQ the IRs they sell but will offer several mic positions instead.
But some IR producers will do some EQ'ing.
The companies that offer "Mix" IRs, taken form several mics at once, usually do some rudimentary EQ'ing even of their single mic IRs.
But in my experience even these need some further EQ.

Personally, I'd like to see the EQ section in the Amp Block expanded to at least a 3-band full parametric.
But I doubt that Cliff will do this because it would increase the already large CPU hit that the Cab Block imparts now.
The 3-band EQ available in the Cab Block's Preamp section now doesn't seem to really get to the frequencies that I need for taming the IRs I need to tame.
Of course we can just add a post Cab Block a PEQ Block now and accomplish the same thing as what I'm advocating.

I think that most of us have had issues with the Cab Block over the years because for most of us the thing we really want to capture into our FRFR systems is the sound of a real cab in the room because that's what we're the most familiar with from playing real amps.
There are people, like Jay Mitchell, who claim that this CAN be done using far field IRs (possibly mixed with room and back-of-cab IRs), but I've never been able to get there.
So "settling" for a good mic'd cab tone is pretty much the state-of-that-art at the moment.

But I've often advocated for a different type of cab simulation in the Axe, one not based on IRs but rather on sophisticated and powerful multi band EQs designed to help the player achieve a frequency response curve out of an FRFR speaker that is very close to the frequency response of a guitar speaker.
I've tried several times over the years to do this with the EQs and Filters already provided in the firmware, but have never really gotten anything satisfactory.
But I have come close.

It's the Red Box/Palmer PDI approach vs the cab IR approach.
There are IRs of both the Palmer and the Red Box floating around but they never seem to be as satisfying as real cab IRs.
So I think that that tells me that even if I could do a near perfect EQ-based cab sim I'd probably opt for a real cab IR anyway.
lol

But then I don't play FRFR live.
I'm an an power amp + real cab guy.
I only use FRFR for recording at home or to send to FOH if I don't want to deal with a mic on stage.
But usually I'll just let them mic me.
Same in the studio.

So I've learned to just trust Cliff over the years.
He know a LOT more about ALL of these issues than anybody and he's on our side.
He knows what we really want.
He knows what we really need.
And he knows how to give it to us at the level of the current state-of-the-art.

Let your hunt for the perfect IR begin, if it hasn't already.
 
I haven't owned any real-deal good amps or played loud with them, except a Fender Twin about 25 years ago. I am a non-metal guy, enjoy a range of clean sounds and near-breakup sounds, and every once in a while go crazy with a super-sloppy over-the-top Hendrix meltdown type sound, or play for a few seconds with something real high-gain. But very clearly, at this point the sound of the Axe is not at all my limiting factor. I just need to play more and get better at that ;)

When I turn on the default settings of 59 Bassguy with any of a handful of stock cabs (with the hi/lo cuts at 80-110Hz and 6200-8800Hz), it sounds pretty freakin' awesome and real in the room to me. Definitely need to tweak it for a band mix to carve out space for a bass player or a lead guitar if I am playing rhythm, but just playing loud in a room sounds blissful.

One of the key things seems to be literacy in how to articulate what you want and manipulate the sound blocks to achieve it, if you are picky about wanting a very specific sound. Each firmware release seems to make it easier to get a amazing sound with less tweaking. At this point the hi/lo cuts in the cab and the cab selection, and adjusting input gain and master volume, BMT, are about the only things really necessary. I still like to turn up Sag sometimes to make it more squishy sounding, or turn up Negative Feedback to make it clean up slightly with a cutting but pleasant clarity. Anything else is more of a science project just to see what the knobs do.
 
........ I'll typically set the high frequencies to cut off at on or just under 3k. However, the other day, I noticed on my strat I noticed that the clean and semi-clean tones were just super zingy and the bridge pickup was ice-picky. So, I set the high freq cutoff to 4k. WHAT A DIFFERENCE!!! .........

Hey

Just a bit confused.

Are you saying that at around 3kHz hi-cut your strat was still a bit too zingy / ice-picky ..... but when you raised the hi-cut to 4kHz it got less zingy / ice-picky (?)

Apologies if I have misunderstood.

Also, FWIW, I had all but given up on getting "real" cab tone and feel out of my Axe / Kemper + CLR combo ..... like many I had spent a small fortune on all the "ususal" top shelf IR's packs ........ numerous options but none really captured the "real" I was after.

As a last roll of the dice, I found a reference to 3 Audio Sigma Cab IR's on TGP ... never heard of them before ..... long story short, I have re-started using my Axe and Kemper with my CLR .. they are the only IR's I have tried that make my FRFR rig feel and sound like my real rig ... and for these all I simply do is low-cut up to around 95Hz<-> 100Hz and hi-cut down to around 3700kHz <-> 4200kHz and in the Axe, I have Mic set to none ...... bingo :)

Hint ..... Zilla 2 x 12 pack .... has 10 IR's ......... IR 3B is my go-to ......... set lo/hi cuts to taste ....... Britsh crunch / dirty bliss :) ..... and its only $7 !?!?!?!?!?!?!?!? ..... just redonkulous .... I also have their Friedman ..... wow .....

Ben
 
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