Low Cut, High Cut

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Continuing in the new user tips theme...

People often talk about applying low cuts and high cuts. This is because the cabinet models used in modelers are almost always (with a couple exceptions) based on near-field samples of guitar cabinets. IOW, the mic is pushed up against the grill cloth. This just happens to be the way that record producers/engineers mic a cabinet in the studio and the way guitar cabs are mic'd on stage. This is done primarily for isolation reasons.

The downside of this approach is that the resulting tone will have a lot more lows and highs than when listening to the amp+cab "in the room". What the mic "hears" when pushed up against the grill cloth is not the same thing that we hear standing 10 feet away.

The most common technique to deal with this is to simply cut out the lows and highs using blocking filters, e.g. highpass and lowpass filters. Producers routinely do this when mixing as excessive amounts of lows and highs will cause the guitar tracks to get "lost in the mix". Live sound engineers often do the same thing.

The Cabinet block has blocking filters built in for just this very reason. You can also use a couple dedicated filter blocks or a parametric EQ block. For now let's use the Cabinet block. My personal settings are Low Cut around 80 Hz and High Cut around 7500 Hz and Filter Slope set to 12 dB/octave but these are just a starting point.

Far-field IRs are available but they are rare due to the difficulty in obtaining them. They require a large facility and special techniques making the process impractical in most cases. So, until an abundant source of far-field IRs are available we need to think like a producer/engineer who is dealing with the mic pushed up against the grill cloth. This means shaping the tone with EQ to remove unwanted frequencies.
 
Thanks Cliff, this is pretty much one of the first things I do when making a preset. I think I set the high to something like 9000 and start to trim down from there based on the amp model. I also add a PEQ block right before the amp block and I cut 300 by 4-6db that's a trick Scott Shared with us a few years back and it works great.
 
I also add a PEQ block right before the amp block and I cut 300 by 4-6db that's a trick Scott Shared with us a few years back and it works great.

You can also use Low Cut Freq in the Amp block
 
I'd like to think there is some sort of arms race going on amongst IR producers to deliver a solid far field IR collection but from the sounds of it, the returns wouldnt justify it?
 
You could cut in many blocks.
Do you only do hi/low cut in the cab block, and leave hi/low cut at default in other blocks?
 
I'd like to think there is some sort of arms race going on amongst IR producers to deliver a solid far field IR collection but from the sounds of it, the returns wouldnt justify it?
It's a bit more complicated than that. Moving the microphone further away from the cabinet does IMO not produce "amp and cab in the room feeling". The industry standard for guitar tones has been close miked cabinets for pretty much forever.

Once you start pulling the mic away it's less about the actual cabinet and more about the room you're using. Your mic starts to capture more than one speaker simultaneously and all the reflections from the walls, floor and roof etc. Usually what you end up with is something really honky and phasy sounding with a long reverb tail. (Longer than the Axe-Fx IR format) Actually it would make more sense to just shoot room IR's that have nothing to do with the cabinet and use those IR's for an extremely natural reverb but personally I think the reverb block in the Axe-Fx does the job really well.

I think this is something that's really interesting and I'm sure many people would love to try it out but I have a feeling it's something that will not sound as good as the IR's we have now and the majority if not all people will agree. It's all speculation though. I love IR based reverbs so I'm sure it'll sound awesome but it's not going to be a night and day difference between a high quality reverb.
 
Here's what I don't understand...My ears are 10' away from my monitors, why doesn't that do what a far field IR would? I mean, if the IR is capturing exactly what is coming out of the guitar speaker (modified by the mic, of course), why isn't that going to be dead bang on what I need coming out of my monitor?
 
Some great advice there mr Cliff.
I always had trouble figuring out what a good high cut frequency was. I guess just close your eyes and listen...

Anyone here care to say what kinda settings you might use in a bass tone?
 
Here's what I don't understand...My ears are 10' away from my monitors, why doesn't that do what a far field IR would? I mean, if the IR is capturing exactly what is coming out of the guitar speaker (modified by the mic, of course), why isn't that going to be dead bang on what I need coming out of my monitor?
Your monitors [ideally] put out a carbon copy of the sound pumped into them.

That sound is crafted using a simulation of a speaker cab (as a cab "filters" the harsh noisy sound that comes out of an amp into a pleasant range).

That simulation was created by close-miking an actual cab. This is how we are able to replicate the intricate function of a cab - essentially by using in real-time a sample of an actual cab.

Thus, you are hearing a close-miked sound from your monitors regardless of your distance from them.
 
Anyone here care to say what kinda settings you might use in a bass tone?
For just a simple high cut and low cut setting? I would say around 50Hz for low cut and 4kHz or upward for high cut.

If you start splitting up your bass signal between DI, Amp and Distortion; then it gets a little more complicated.
 
Simple- you want mic'ed tone for foh, you got it. If you want amp in the room, use a nice clean power amp (for me fryette power station) into a cab and wallah amp in the room :) I love having both setups and sounds to switch between.
 
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It's a bit more complicated than that. Moving the microphone further away from the cabinet does IMO not produce "amp and cab in the room feeling". The industry standard for guitar tones has been close miked cabinets for pretty much forever.

Once you start pulling the mic away it's less about the actual cabinet and more about the room you're using. Your mic starts to capture more than one speaker simultaneously and all the reflections from the walls, floor and roof etc. Usually what you end up with is something really honky and phasy sounding with a long reverb tail. (Longer than the Axe-Fx IR format) Actually it would make more sense to just shoot room IR's that have nothing to do with the cabinet and use those IR's for an extremely natural reverb but personally I think the reverb block in the Axe-Fx does the job really well.

I think this is something that's really interesting and I'm sure many people would love to try it out but I have a feeling it's something that will not sound as good as the IR's we have now and the majority if not all people will agree. It's all speculation though. I love IR based reverbs so I'm sure it'll sound awesome but it's not going to be a night and day difference between a high quality reverb.

A far-field measurement is more than just pulling the mic back. You need to perform this measurement in a sufficiently large space so that there are no reflections from the walls and ceiling until AFTER the direct signal is obtained. The microphone, usually a measurement mic like an Earthworks, is setup to make a "ground plane" measurement. This means putting the mic capsule almost touching the floor. The signal captured by the mic is then the direct path first and any reflections occur later in time and can be removed. Another option is an anechoic chamber but that's even more impractical due to the scarcity of such chambers and the associated cost.

It's still no panacea though as what we hear in the room is a combination of direct and reflected sound. A far-field IR captures just the direct sound but when we listen to a guitar cab we are hearing the direct sound plus a reflection off the floor (and later reflections from the walls and ceiling). That's partly why a cab on the floor sounds different than raising it up on a stand or tilting it back. As you raise or tilt the cab the floor reflection path length changes.

Personally I doubt we'll ever get IRs that sound exactly like listening to a cab "in the room". If you want that sound, IMO, then use a traditional cab. Our products were the first to allow the user to send a signal with cab modeling to FOH and tap off before the cab modeling and send that to a traditional cab. Best of both worlds.

For me personally I just use the high and low cuts and I get great tones through my studio monitors. This is what they've been doing in recording studios for decades and there's no denying how great the guitar tones can be.
 
Here's what I don't understand...My ears are 10' away from my monitors, why doesn't that do what a far field IR would? I mean, if the IR is capturing exactly what is coming out of the guitar speaker (modified by the mic, of course), why isn't that going to be dead bang on what I need coming out of my monitor?
Because you're listening to that "in the room" sound...in a room.

That's two rooms worth of reflections, all piled on top of each other. It's not the same.
 
Just tried the 80/8000 settings in a few of my main patches and on my Tannoy monitors I'm not really noticing a difference. I don't cut frequencies any other place with this kind of precision, so maybe I've just naturally chosen IRs and AMP block settings that trim the top and bottom off already? Would this be something I'd notice more clearly at stage volumes instead of near field monitoring volumes? Presumably it offsets some fletcher-munson-y stuff as you crank up the volume?

I'll have to try it with some tracks...see if I slice a little better with the cuts in place.
 
Just tried the 80/8000 settings in a few of my main patches and on my Tannoy monitors I'm not really noticing a difference. I don't cut frequencies any other place with this kind of precision, so maybe I've just naturally chosen IRs and AMP block settings that trim the top and bottom off already? Would this be something I'd notice more clearly at stage volumes instead of near field monitoring volumes? Presumably it offsets some fletcher-munson-y stuff as you crank up the volume?

I'll have to try it with some tracks...see if I slice a little better with the cuts in place.

I use 7500 for the high cut but that's pretty close. Also be sure the filter is 2nd order (12 dB/oct.). It probably depends on your hearing as well. Despite playing in rock bands for 25 years and not wearing any hearing protection I can hear up to 15 kHz. If you hearing has been damaged by loud music then you may not be able to hear the effects.
 
I use 7500 for the high cut but that's pretty close. Also be sure the filter is 2nd order (12 dB/oct.). It probably depends on your hearing as well. Despite playing in rock bands for 25 years and not wearing any hearing protection I can hear up to 15 kHz. If you hearing has been damaged by loud music then you may not be able to hear the effects.
My ears are...not so great any more. :(
 
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