Impulse responses, why? Why not?

[nan_wpg]

I’m going down the rabbit hole of impulse responses. 
 

I understand what they are, but what are the line6 cabinets? I.e they aren’t IR’s so what are they?

 

if IR’s are the way to go then why didn’t line 6 put them in the helix to begin with? 

[theElevators]

I personally find my ideal sound with Mail Order Twin combo amp + cab with default virtual mic placement.  I thought it was a Fender Twin based on the name, but turns out it's that Sears crappy amp from the 1960's that guitarists like Jack White use.  Long story short, it's got my sound, and I copy-pasted it into all of my presets.  I don't need anything else. 

 

The main advantage of using what's already in the Helix is that you have the various parameters like the mic placement you can control.  An IR does not.

 

I did briefly experiment with IRs to reproduce an acoustic guitar sound.  This was before Helix had the acoustic simulator.  Now I have no use for it. 

[mnolan98]

Cabinets simulate speakers and microphones. Impulse responses, to the best I can explain, uses impulse recordings from speaker / mic combinations to then be processed.  So IRs are not simulations. 
 

I have used both. I’ve found IRs to have a better overall presence, crispness and liveliness.  When running them you can run at a higher quality and lower quality - I’ve only used the higher and never really compared the two to see if I hear a drastic difference. 
 

At the higher quality, IRs are more computationally intensive (so there is definitely a trade off to consider). I find that I have fewer delay options on my main templates and configurations. But I can usually tweak it to get enough computation / block space open. 

 

Many IR packs out there give lots of combinations (console recorded in / mic position / distance / microphone).  While many are also there in the simulator, console isn’t. And there is often more microphones. So you can be overwhelmed with options (which I find distracts from the creative process). 
 

in the end, I’ve not looked back after switching to IRs. 

[jrbtaylor]

It's important to understand that they're both just an EQ. A really nuanced EQ, but still only an EQ.

 

The Helix cabs are approximating the same thing but instead of being restricted to whatever mic position the IR was captured at you can move it around. It's more flexible but arguably losing some of that nuance.

 

FWIW I've usually had the best results blending an IR with a dual Helix cab, but if you want something simple that's plug and play, get an IR pack from York Audio and try the mixes. 

 

[soundog]

Consider the Helix Cabs to be IRs, so use one or the other. Also, there are plenty of blind tests comparing Helix cabinets vs IRs. Find 'em on youtube. Most folks can't tell a difference when everything is adjusted to be as normalized as possible. I've experimented with commercial IRs quite a bit, but have recently settled on using the stock cabinets primarily because:

1) Amp+Cab only uses one block in the Stomp

2) When I spend time trying to adjust a stock Cab to sound like a given IR, there is minimal difference

3) You can adjust the mic, mic distance, early reflections, hi cut, lo cut "on the fly" with stock Cabs. With IRs you normally have to choose between a long list of variables, and then are locked in to that choice.

4) The stock Amp+Cab choice already matches the amp with cabinet.

5) Stock cabinets save a lot of time and money over IRs.

 

You'll find plenty of folks that swear by IRs, and that's just dandy. If you want, spend some time deciding/researching which path you want to take. Or use both. But I personally don't think you're missing anything by sticking with the stock cabinets.

 

 

[nan_wpg]

38 minutes ago, mnolan98 said:

Cabinets simulate speakers and microphones. Impulse responses, to the best I can explain, uses impulse recordings from speaker / mic combinations to then be processed.  So IRs are not simulations. 
 

I have used both. I’ve found IRs to have a better overall presence, crispness and liveliness.  When running them you can run at a higher quality and lower quality - I’ve only used the higher and never really compared the two to see if I hear a drastic difference. 
 

At the higher quality, IRs are more computationally intensive (so there is definitely a trade off to consider). I find that I have fewer delay options on my main templates and configurations. But I can usually tweak it to get enough computation / block space open. 

 

Many IR packs out there give lots of combinations (console recorded in / mic position / distance / microphone).  While many are also there in the simulator, console isn’t. And there is often more microphones. So you can be overwhelmed with options (which I find distracts from the creative process). 
 

in the end, I’ve not looked back after switching to IRs. 

I find the helix itself can distract from the process. I can see impulses even more so. 
 

and yet I just watched “get back”. The Beatles were quite limited equipment wise but yet produced some of the best music out there. 
 

my goal is to replicate my actual box ac30. I mean how many guitarists actually have 200 amps and cabinets?  
 

I just want a killer amp preset and I’ll treat it like a real amp. 
 

but the question is why didn’t line6 include ir’s?

[nan_wpg]

So looking at aftermarket “presets” are they using the existing amps and effects? And just their own custom ir’s?  Or can they do their own amps and effects as well?

 

some of them claim to reproduce “classic” or boutique amps. How are they doing this?

[Anderton]

2 hours ago, jrbtaylor said:

It's important to understand that they're both just an EQ. A really nuanced EQ, but still only an EQ.

 

Yes, that's a good distillation. I even create some cabs using only EQ, the sound seems more "analog" sometimes and requires less processing power. Blue Cat audio also relies on post-amp filtering in their Destructor plug-in to give cabinet-like curves. The sound is not as nuanced as IRs or the modelled cabs, but you can customize the sound quite a bit with EQ. 

 

I did an article for inSync about how to create EQ-based cabs with Helix. Three audio examples compare the Helix modeled cabs with EQ-based cabs, so you can get an idea of their different "characters." Sometimes EQ by itself can be a good alternative to modeled cabs or IRs.

[DunedinDragon]

I exclusively use IRs, not because they're any better than stock cabs, but just more convenient.  That's because I use a LOT of presets for different songs and guitar configurations and it's much easier to simply select from a list of selected IRs than to constantly dial something in.  It's also easier to make comparisons of how different cabinet and mic setups will affect a given preset.

[PierM]

11 hours ago, nan_wpg said:

but the question is why didn’t line6 include ir’s?

 

Because they have Cabs, and the IR block does just give you the opportunity to expand the possibilities, adding your own preferred IRs. A single IR set, from a specific amp, can be hundreds of IRs, like different Mics, different angles, different offset, different distances from the cone etc.. It can be a rabbit hole. The procedural helix Cabs can do all of that with just an algorithm, apart the Mic offset from the Cone.

 

Since the IR room in the Helix is not infinite, in fact it's pretty limited, I think was a good idea to not fill it with a predefined set of IRs, which would have been a bit of a redundant move - as there are procedural Cabs, that many times can basically match a given IR, if properly setup (especially IRs with Mic aligned to Cone Axis).

[codamedia]

On 12/4/2021 at 5:40 PM, nan_wpg said:

I understand what they are, but what are the line6 cabinets? I.e they aren’t IR’s so what are they?

 

When someone uses the term "IR" they are usually referring to a static IR. It's a single tone capture of "Cabinet/Mic/Mic Placement" and any combination of those. Outside of "low/high cuts" there is nothing you can do to manipulate those sounds. If you want a different mic placement, you NEED to create a new IR. That's why libraries come with huge amounts of files... every inch the mic is moved a new file is created. 

 

Some company's (two notes as one example) now offer dynamic IR loaders... and people make special IR's that can be manipulated with these loaders. With those you simply choose the CAB/SPEAKER combo you want... and within the one IR you can choose mics, mic position, resonance, reflections, etc... etc... NOTE: A dynamic IR cannot be loaded into a standard IR slot. They are created for specific loaders. EG: Two notes has their system, Celestion has their system, Fractal has their system, etc... etc... 

 

Line 6 Cabs fit in the "proprietary dynamic category" of IR's... but (IMO) with a couple glaring omissions. They don't give you the ability to move the mic from "speaker center" toward "speaker edge"... or angle (off-axis) the mics in any way. You also cannot add multiple mics to a single cab.

 

IMHO... Although the built in cabs can sound good, it is their limitations that push some people toward the other option of static "IR's"... including myself. 

 

 

 

[Hey_Joe]

shedding more light on the question...

 

From Line 6's Helix blog

What The Heck Is An IR?

[Anderton]

FWIW it's easy to capture IRs yourself, of cabs from other amp sims. It's much easier than capturing IRs from physical cabs and mics. I have some AmpliTube cabs I use in Native.

[soundog]

14 hours ago, codamedia said:

 

....They don't give you the ability to move the mic from "speaker center" toward "speaker edge"... or angle (off-axis) the mics in any way. ...

 

Yes, that is certainly a big omission. Most of the difference I heard from same-mic IRs moving from center to edge is eq; bright (center) to dark (edge). So, being a stock cab user, I always add a tilt eq block after the cab, and do a slight tweak i needed to simulate the eq change from mic positioning. I find that adjusting this, along with a sprinkle of early reflections does the trick for me.

 

[codamedia]

7 hours ago, soundog said:

So, being a stock cab user, I always add a tilt eq block after the cab, and do a slight tweak i needed to simulate the eq change from mic positioning.

 

I use stock cabs a lot in the studio... and that's exactly what I do to simulate the "center > edge" movement. 

For live use I really like a few of the IR's from Michael Britt so I've been using those instead of the stock cabs.  

 

9 hours ago, Anderton said:

FWIW it's easy to capture IRs yourself, of cabs from other amp sims. It's much easier than capturing IRs from physical cabs and mics. I have some AmpliTube cabs I use in Native.

 

I've done a bit of this myself from hardware... creating IR's of my old PDI-03 (Palmer) and Mesa Cab Clone. 

I've also captured my favorite presets from my Fishman Aura and JD Aura. It saves me from hauling all those around for my acoustic, banjo, mandolin and dobro. 

[soundog]

Ya know, I bought the Michael Britt Helix pack over 5 years ago, and still love it. The presets include his bundle of 30 IRs. The presets have none of the newer amps, no snapshots; it's simply tasty meat-and-potatoes clean tones and mid-lead gain overdrives. I bought a bunch of third-party presets before I learned to roll my own, and I think his pack may be my favorite. Michael hasn't done any updated packs for Helix, 'cause he's a big Kemper fan. But I highly recommend both his Helix pack ($30) or just his IR pack ($20)

[cfhmonkey]

Definitely in agreement on the Michael Britt Helix pack.  I ended up re-working my entire live setup on the Helix, switching over to his amp blocks exclusively - even though he doesn't use any of the newer amp models. He definitely has golden ears (and hands). The difference in tone and touch sensitivity has been quite noticeable. Thanks, Michael!

[jonny4rd]

I look at IRs (and profiles) like keyboard samples. They are one snapshot of a specific output with a specific mic on a specific cab at a specifc point on a speaker at a specific impedance etc. 
In contrast, amp/cab modeling (like physical keyboard modeling, where it probably gets its name) appears to be more of an attempt to create a virtual representation of an amp or cab in a myriad of the aforementioned conditions.  

It’s been said many times that an IR is a essentially photograph.  As such, today’s modeling is probably more like a VR representation of the amp that you can interact with in real time at different angles in different rooms etc. Like multiple IRs (or perhaps parts thereof) being used at once. This might be why modeling puts so much more demand on system memory than static IR's.  
I suspect early cab  “modeling” was little more than IRs but might be wrong there.  I also suspect machine learning has been used to add realism to models for a long time. And now that AI technology is more affordable and companies have all these reference data points on amp/cab behavior machine learning is blurring the lines between static IR capabilities and dynamic modeling. 

 

Sansamp proved long ago that simple eq could get us a 90% solution to the problem of replicating a guitar cab.  It’s always that last 10% that keeps us up at night.  Or in my case why none of the Celestion blue models or IRs seem to have the magic mids that a real one does.