Do we really need amp sims?

August 2019 is the first KVR Guitar Month so here's a new forum for discussion of all things guitar!
User avatar
JO512
KVRist
202 posts since 9 Nov, 2018 from Colorado

Post Mon Jul 13, 2020 11:51 am

I've been playing with waveshaping, EQing, and impulse responses and have come to the conclusion that I can get tones that rival amp sims, overdrive/distortion pedal sims, and so on, with nothing more than a good EQ, a simple waveshaper, a compressor, and an IR loader with some decent cab IRs (many available for free).

I am no DSP expert, but it seems to me that in the end, all distortion/saturation in the digital world is ultimately just waveshaping, even if you achieve it by simulating circuits in amps or pedals or whatever. A waveshaper likely does everything we need here. And doing it directly is probably much more computationally efficient than simulating a bunch of capacitors and inductors and so on.

If you just push your guitar signal into a waveshaper with no modification, it will sound pretty bad. To get nice distortion tones, I've found that you need to do some EQing/filtering before the clipping stage, most importantly to diminish a lot of the low frequencies, as heavily distorted low frequencies contribute a lot of mud and "flubberiness", if you will. EQing again after a clipping stage can be used to bring back some bass, some highs, or whatever else was cut before clipping.

I've been getting good results just using a two or four pole bandpass filter before clipping the signal fairly aggressively with a simple waveshaper like MWaveShaper or the waveshaper in Trash 2 and then bringing some bass and highs back up and maybe cutting some mids a bit in certain places. I can get tones this way that sound to my ear as good as those produced by amp sims in Amplitube, Neural DSP's plugins, and so on. And I have so much more control! And everything is much more intuitive, as I can see what I am doing with my EQ. Often, the controls on amps and amp sims are a bit of a mystery to me and a matter of trial and error. And some of those knobs do so very little! Doing things with a modern digital EQ makes it all so much easier to understand. You can see what you are doing to the signal.

Much of the good tone seems to depend on having good cab IRs after the distortion and EQing. And of course, then you might like some delay, reverb, and so on. And you can add compression at any stage you like if you want it. You can even simulate sag with a compressor. A dynamic EQ or multiband compressor can be useful as well.

Has anyone else experimented along these lines?

I feel quite liberated by this, honestly, as I am tired switching from amp sim to amp sim, tweaking knob after knob, trying demo after demo, emptying my wallet for plugin after plugin, trying to find the tone I am after. Now that I think I've basically understood how to do the most important things to the signal in a simple way at a basic level, I don't need to spend so much time fiddling, not to mention being suckered by all the fancy marketing and packaging that goes with all the guitar plugins.

Some of those plugins are downright beautiful, Neural DSP's especially! That imagery is so good that it makes your guitar seem to sound better! And some have great presets if you want to just have it all done for you. But if you want much more control over your tone and can live without the gorgeous imagery and the fantasy that you are using a classic tube amp, I suggest experimenting along these lines.

The last thing here I'd like to do is to liberate myself from IRs. I've experimented with EQing instead, and I can get somewhat decent results sometimes, but IRs add that boxy, resonant cavity sound that you can't get with EQing alone. They give the tone a special voice-like character. Adding some feedback to resonant filters can get you closer to a cab sound, but things start to get a bit complicated there.

I hate going through hundreds of IRs scattered across different folders, trying to find something that fits in the mix! And buying IRs is such a leap of faith. You don't know what you are getting! I'd like to have a way to shape the cab tone just how I want it in a way that is as direct and intuitive as using a graphical EQ.

fese
KVRian
1307 posts since 14 Sep, 2004 from $HOME

Post Mon Jul 13, 2020 12:24 pm

Frankly, this sounds more complicated to me than just loading a dedicated amp sim, especially one with a good UI that doesn’t have dozens of amps, cabs and microphones in order to prevent option paralysis (like the neural stuff or the Fuse F-59).

lfm
KVRAF
5360 posts since 22 Jan, 2005 from Sweden

Post Mon Jul 13, 2020 5:22 pm

I tried using Trash v1.0 15 years ago or so. Explored every corner of that - and consider that an amp sim.
Tried every dist model in series and parallell and whatnot.
Most profound for tone I found was box models(cabinets).
But always something digital about it so I tried using external tube pre amp like Womanizer.
Closer but not good.

An amp respond very differently - and modern amps are very much adapted to recording situtations with own cab sims outputs etc. So if wanting everything from clean to metal amp is best way and doing so just altering how you attack strings with pick. The tweaking you are into now seems very cumbersome and for one type of tone it sounds to me.

The dynamic response an amp give is nothing like you can tweak with EQ and some IR's. I'm thinking pretty much heavily saturated metal tones or something. And this is what Kemper and AXE FX do technically and very costly solution. You can buy 4 decent full tube amps of various type of sound for the same money.

If to get one amp I would suggest Laney Ironheart Studio. You don't even need a speaker connected, it transform into 1W amp and internal load if you do that. 3 channels with foot switch and large variety of tone from clean, blues to hi gain. This is all tube then and rack mount. You also have a gain boost knob accessible on/off at foot switch, that works on all 3 channels. Two full sets of EQ that also have pull switches to alter crossover frequency.

But Fender Mustang series I think are decent with their internal amp sims and some stuff like former Fuse that go with my Superchamp X2 that allow to configure a lot and load models+stomp boxes into hardware.

I cannot see the tweaking you do is a long term solution. You will get fed up with all that tweaking every project unless going metal hi gain every time.

Chrisk-K
KVRist
113 posts since 4 Jun, 2020 from USA

Post Mon Jul 13, 2020 5:41 pm

Just use Helix or Kemper. Much easier and sounds fabulous.

User avatar
telecode
KVRAF
1935 posts since 24 Mar, 2015 from Toronto, Canada

Post Mon Jul 13, 2020 6:56 pm

anything is possible. i can only speak for myself. i feel i need am amp sim and also an amp sim that kind of looks like it has knobs that an amp has, that way i able to easier navigate the setting in trying to achieve the sound i am going after and not randomly guessing and experimenting with plugins and not knowing what i will get. so if i am envisioning a sound that has solid state with 15% over driver and certain delay setting, i can get it in a reasonably fast time but adding things and moving knobs that i am familiar with in real life. i guess thats why i need amp sims.

ijiwaru
KVRist
75 posts since 25 Oct, 2019

Post Mon Jul 13, 2020 9:12 pm

I like this approach because, to a certain extent, it allows you to circumvent the confirmation bias that accompanies amp sims (i.e. 'this plug-in looks like an AC30, so it must sound like an AC30') and focus entirely on the sound.

Have you tried using a tunable filter bank to approximate the resonances of a cabinet? Given that IR convolution based cab sims are basically just static filters it could possibly yield a more dynamic resonant cavity response.

One thing you neglected to mention is the use of reverb to simulate room tone, an essential component for more realistic amp sounds. In my experience algorithmic reverbs work best in this regard. You only need a tiny amount of decay, somewhere between 40-70 ms usually works, no pre-delay or modulation.

Another thing worth trying is adding very small amounts of filtered white noise to imitate amp hiss.

schpaeckulum
KVRist
38 posts since 26 May, 2020

Post Mon Jul 13, 2020 9:26 pm

JO512 wrote:
Mon Jul 13, 2020 11:51 am
I am no DSP expert
That is correct.

lfm
KVRAF
5360 posts since 22 Jan, 2005 from Sweden

Post Mon Jul 13, 2020 9:33 pm

ijiwaru wrote:
Mon Jul 13, 2020 9:12 pm
Have you tried using a tunable filter bank to approximate the resonances of a cabinet? Given that IR convolution based cab sims are basically just static filters it could possibly yield a more dynamic resonant cavity response.
Nebula is a plugin that I think can load a lot of IR's and sort of emulate various non-linear as morphing between IR's loaded. That's how I understood it anyway. Looked at it like 10 years ago.

But OMG what it uses cpu, it's a cpu hog for sure. Lets say you need 10 IR's to represent various levels of distortion, dynamically, and this takes some effort.

But as you say - IR is pure linear - and distortion in an amp is non-linear. So to respond like a guitar tube amp do when picking lite or harder or very hard you get different response.

Speakers will have this behavior too, but maybe lesser degree than an amp that is saturated.

User avatar
jamcat
KVRist
316 posts since 2 Sep, 2019

Post Mon Jul 13, 2020 10:13 pm

Alright, let's put it to the test.

You said you could get tones as good as AmpliTube and Neural DSP.

Here are some audio clips. Let's hear how close you can come, and how long it takes you:

AmpliTube Joe Satriani:
AmpliTube clean
AmpliTube drive
AmpliTube crunch
AmpliTube lead

Neural DSP Nolly: (h/t Geeky Gear Guy)
All Nolly Presets

User avatar
excuse me please
KVRian
513 posts since 10 Oct, 2018

Post Mon Jul 13, 2020 10:41 pm

Thinking that way.. do we really need guitars? I just load up a synth :)

anomandaris1
KVRist
432 posts since 26 Nov, 2009

Post Mon Jul 13, 2020 10:56 pm

excuse me please wrote:
Mon Jul 13, 2020 10:41 pm
Thinking that way.. do we really need guitars? I just load up a synth :)
For heavily distorted sound - you don't need guitar... you can start from a synth tone and the result will be the same.

I wonder why is there no "synth metal" (or at least, it is rare - some dnb records come to my mind)

User avatar
Gamma-UT
KVRAF
5804 posts since 8 Jun, 2009 from UK

Post Mon Jul 13, 2020 10:59 pm

JO512 wrote:
Mon Jul 13, 2020 11:51 am
I've been playing with waveshaping, EQing, and impulse responses and have come to the conclusion that I can get tones that rival amp sims, overdrive/distortion pedal sims, and so on, with nothing more than a good EQ, a simple waveshaper, a compressor, and an IR loader with some decent cab IRs (many available for free).
An amp sim is more or less that. Though you probably want a waveshaper that responds to level changes - that’s more or less how the Blue Cat guitar amp emulator works. Even the cab responses in that are comb filters and EQ.

User avatar
excuse me please
KVRian
513 posts since 10 Oct, 2018

Post Tue Jul 14, 2020 12:23 am

anomandaris1 wrote:
Mon Jul 13, 2020 10:56 pm
excuse me please wrote:
Mon Jul 13, 2020 10:41 pm
Thinking that way.. do we really need guitars? I just load up a synth :)
For heavily distorted sound - you don't need guitar... you can start from a synth tone and the result will be the same.

I wonder why is there no "synth metal" (or at least, it is rare - some dnb records come to my mind)
It's not easy to get a nice heavily distorted sound, though. I started out with a very harsh sound with lots of unwanted artifacts. But hey.. if you get the digital distortion right, then there's nothing like it!

User avatar
Gamma-UT
KVRAF
5804 posts since 8 Jun, 2009 from UK

Post Tue Jul 14, 2020 12:31 am

anomandaris1 wrote:
Mon Jul 13, 2020 10:56 pm
excuse me please wrote:
Mon Jul 13, 2020 10:41 pm
Thinking that way.. do we really need guitars? I just load up a synth :)
For heavily distorted sound - you don't need guitar... you can start from a synth tone and the result will be the same.

I wonder why is there no "synth metal" (or at least, it is rare - some dnb records come to my mind)
There are three answers:

1) There have been a few synth-metal acts but it all got subsumed into "metalcore" which is more synth-heavy metal that still uses guitars.

2) "Synth metal" is actually called industrial.

3) Why would you want to? Trying to do metal riffs on a keyboard is a hiding to nothing, though widdly diddly solos with one hand on the pitchbend are feasible. You're way better off with an axe: the movements are a lot more natural.

Also, most synth sounds are pretty full. An unamplified electric guitar signal is weedy by comparison. Put both through pedals and a high-gain amp and you've got a hot mess with the synth.

You could probably do double-kick finger drumming on a keyboard or set of pads reasonably well though.

User avatar
jamcat
KVRist
316 posts since 2 Sep, 2019

Post Tue Jul 14, 2020 1:23 am

excuse me please wrote:
Mon Jul 13, 2020 10:41 pm
Thinking that way.. do we really need guitars? I just load up a synth :)
https://youtu.be/6RWdEj5tdpk

Return to “Guitars”