Can you emulate a speaker cabinet with amp EQ?

[alexa3020]

If you have a clean cabinet (FRFR or getting towards it maybe), is it possible to emulate a coloured cabinet sound with just amp EQ?

When playing around with cab simulations, to my ears it just sounds as if an EQ is being overlayed on top, which is definitely taming the harshness of the treble, warming the sound and probably bumping or cutting some other frequencies.

If that's the case, would you always be better going for a clean sounding cab because it offers way more versatility?

[PaulWarning]

as far as I am aware this is what amp and speaker simulators do perhaps with distortion and compression as well

[fretmeister]

Partly. A speaker is effectively a really complex EQ curve.

 

But a speaker is not a static EQ curve - it changes depending on what is feeding it. So an EQ with enough bands / parametric can get you close it will never be exactly the same.

 

The image below is one that bass nerd Jon Willis made showing his best shot at duplicating an Ampeg 810 (old one and modern) using an EQ. He did it in the Helix to get the freqs right. I use it quite a bit with my Helix.

 

Jon is really god at this sort of thing - he even helped Billy Sheehan set up his current Helix based rig.

 

 

[alexa3020]

Interesting! so in digital speaker emulation they are not allowing for cab EQ to change depending on what is feeding it, they are just overlaying a static EQ on top and getting close?

If you wanted to achieve this with analogue pedals and an amp it is theoretically possible, but you'd need 2 eq's. one to eq your pre-amp on your amp how you like it, and one after the amp preamp (not sure how you would do this)  to replicate the speaker cab.

[0175westwood29]

the problem with trying to do this with an actually amp is the (Eq/cab IR) needs to come after the power section to have the proper effect, something very easy to do in the box on a mac or in helix,QC or kemper however i know of no EQ that can take the power of an amp.

 

for me sending an amp into a powered frfr speaker is also a bad idea as they are powered so obvioous issues there if going into an frfr there so many good pre amps now which have an emulated out that you caould send into something like this.

[warwickhunt]

You are touching on something that I've been experiencing this past year as I've investigated the move to silent stages and IEM.

 

At times, some of the DI / pre pedals that I've used have had IRs / cab sims in them but I've ended up disappointed that all they seem to offer is a bit of a wooly blanket EQ to the tone of the bass/pedal.  Our guitar player is a fan-boy of all things IR etc and he is forever trying to convince me that cab sims etc are what I 'need'... when I've personally felt that maybe the units that have these cab sims/IRs to add to the tone are maybe just not a very good EQ BEFORE the sims are EQd over them (if that makes sense).  I've ended up just using a DI/pre with zero cab sim/IR and EQing my IEM to suit the lack of cab.  

 

[fretmeister]

19 minutes ago, alexa3020 said:

Interesting! so in digital speaker emulation they are not allowing for cab EQ to change depending on what is feeding it, they are just overlaying a static EQ on top and getting close?

If you wanted to achieve this with analogue pedals and an amp it is theoretically possible, but you'd need 2 eq's. one to eq your pre-amp on your amp how you like it, and one after the amp preamp (not sure how you would do this)  to replicate the speaker cab.

 

 

Not necessarily. An Impulse Response of a cab does include time so it does change over time. That time is very short - in milliseconds, but within that time there are very significant changes. That is something that a static EQ cannot do. 

 

Have a look at some YT vids about making your own IRs and you'll see the process. The concept of amp capturing takes it another step to include the amp at the settings being used.

 

The rest of the signal chain makes a big impact too. For example, heavy use of compression will minimise the EQ change over time.

[0175westwood29]

3 minutes ago, warwickhunt said:

You are touching on something that I've been experiencing this past year as I've investigated the move to silent stages and IEM.

 

At times, some of the DI / pre pedals that I've used have had IRs / cab sims in them but I've ended up disappointed that all they seem to offer is a bit of a wooly blanket EQ to the tone of the bass/pedal.  Our guitar player is a fan-boy of all things IR etc and he is forever trying to convince me that cab sims etc are what I 'need'... when I've personally felt that maybe the units that have these cab sims/IRs to add to the tone are maybe just not a very good EQ BEFORE the sims are EQd over them (if that makes sense).  I've ended up just using a DI/pre with zero cab sim/IR and EQing my IEM to suit the lack of cab.  

 

what Pre amps shave you been using? its taken me a while but my current direct setup is a blend of three di ( geddy 2112 and ashdown ctm rack pre) three channels into two notes wall of sound for recording, if i want a silent stage i use a two notes captor on my amps out put (its a peavey 200w) im careful and its fine.

 

also if you play clean without drive or fuzz you could be fine as you are. ir shine when distortion is involved

[alexa3020]

10 minutes ago, fretmeister said:

 

 

Not necessarily. An Impulse Response of a cab does include time so it does change over time. That time is very short - in milliseconds, but within that time there are very significant changes. That is something that a static EQ cannot do. 

 

Have a look at some YT vids about making your own IRs and you'll see the process. The concept of amp capturing takes it another step to include the amp at the settings being used.

 

The rest of the signal chain makes a big impact too. For example, heavy use of compression will minimise the EQ change over time.

Will defo check out some IR capturing  vids thanks.

In my case, I now have a much clearer (more accurate I guess) cabinet. and while I can hear myself much better, it sounds quite sterile when flat. I do have to eq it significantly differently in comparison to my original cab.

It did get me thinking should I be using some sort of cab simulation instead.

[0175westwood29]

6 minutes ago, alexa3020 said:

Will defo check out some IR capturing  vids thanks.

In my case, I now have a much clearer (more accurate I guess) cabinet. and while I can hear myself much better, it sounds quite sterile when flat. I do have to eq it significantly differently in comparison to my original cab.

It did get me thinking should I be using some sort of cab simulation instead.

if your using a frfr its a totally different thing to a normal cab

[alexa3020]

Its not FRFR but it sounds pretty neutral and uncoloured to my ears

[chyc]

It's quite a coincidence that this is the subject of a recent video by Alex at Barefaced. He's an expert in this field. I know this because he tells us he is several times in his videos.

 

 

 

[fretmeister]

Alex's vid is very informative.

 

I don't blame him for also using it to confirm that he is an expert. Because he is. Unlike the rest of us he had the balls to put his money where his mouth was.

[warwickhunt]

3 hours ago, 0175westwood29 said:

what Pre amps shave you been using? its taken me a while but my current direct setup is a blend of three di ( geddy 2112 and ashdown ctm rack pre) three channels into two notes wall of sound for recording, if i want a silent stage i use a two notes captor on my amps out put (its a peavey 200w) im careful and its fine.

 

also if you play clean without drive or fuzz you could be fine as you are. ir shine when distortion is involved

 

BBE Acoustimax / NuX MLD / Tech Para / Tech (original DI) / Fishman Platinum Pro

 

BBE - 'technically' for acoustic instruments and has a Sonic Maximizer built in but works great for electric bass but no drive

NuX - drive/OD and IR but I found it overkill for me, even when dialled back

Tech Para - upgrade to the Tech DI that I had but tbh I found that without some of the options engaged it was a bit weak but with them on it was too full and I needed to EQ it a lot

Tech DI - my original back up incase my amp was to die but in fact my choice for pre amp to desk and IEM

Fishman pro - The least coloured pre and very useable EQ that isn't excessive, no drive option; I'll keep this as the EQ can be switched for my acoustic guitar

[Bill Fitzmaurice]

Alex is correct insofar as what he talks about, which is frequency response. As to whether by looking at charts you can tell what a speaker sounds like, you can. But that's 'charts' in the plural. A waterfall chart will tell you most of what a frequency response plot doesn't. Then there's THD, polar response, power compression and a half dozen more. Speaker emulation devices adjust frequency response, some high end studio plug-ins can adjust some other parameters, but none can do it all. The main thing they can't do is to vary all of the various parameters as a function of the volume that the speaker is being played at. If your charts are going to be truly accurate they have to be measured at various power levels, because they will change at various power levels. Even if you had software sophisticated enough to duplicate all of the charted results at one given power level it wouldn't be able to do so at any power level without an unaffordable level of processing, along with the necessary interface to tell the software at what power level it's operating at any given moment. That would require something with capabilities similar to Klippel analysis. It would be less expensive to run six different speakers.

[0175westwood29]

3 hours ago, warwickhunt said:

 

BBE Acoustimax / NuX MLD / Tech Para / Tech (original DI) / Fishman Platinum Pro

 

BBE - 'technically' for acoustic instruments and has a Sonic Maximizer built in but works great for electric bass but no drive

NuX - drive/OD and IR but I found it overkill for me, even when dialled back

Tech Para - upgrade to the Tech DI that I had but tbh I found that without some of the options engaged it was a bit weak but with them on it was too full and I needed to EQ it a lot

Tech DI - my original back up incase my amp was to die but in fact my choice for pre amp to desk and IEM

Fishman pro - The least coloured pre and very useable EQ that isn't excessive, no drive option; I'll keep this as the EQ can be switched for my acoustic guitar

Are you trying to match them to a cab you have? I have the same sound in the speaker as your di? 
 

The only way for that is ir and something like a two notes cabm+

[warwickhunt]

5 minutes ago, 0175westwood29 said:

Are you trying to match them to a cab you have? I have the same sound in the speaker as your di? 
 

The only way for that is ir and something like a two notes cabm+

 

I like the sound of my amp/cab set up (Thunderfunk>TCRS210) but there's no such emulation (referring back to Alex's video).  However I'm trying to emulate as good an IEM sound as I can; DI/FOH literally is down to whoever is handling FOH but that is ever the case because even if I were to take stick a mic in front of my amp/cab, it would sound different out front any way.  A cab sim to me is just a badly EQ'd amp tone.

[fretmeister]

Ola explaining an IR in very simple terms...

 

 

 

 

 

And a bit more detail

 

 

 

[BigRedX]

My take has always been that the "sound" of the amp and speaker get in the way of your overall sound.

 

We only think we like it because it is a sound that we think we are used to from our favourite recordings where we conveniently ignore that fact that even if there was an amp and cab in the signal chain the sound has been massively manipulated to fit into the overall mix.

 

I now use a Line6 Helix but a lot of the time I don't bother with amp or cab models, and simply pick an EQ and drive instead. When I do use an amp it has been specifically chosen for its distortion sound, and EQ will be adjusted elsewhere. When I do use a cab model it is part of a guitar combo, and again has been picked because I like the final sound from the output and not because of how accurate (or not) a representation of the actual amp it might be.

 

So for me the answer is "yes" but only because I'm not trying to replicate a particular speaker cab, but because I am making a suitable bass guitar sound for my band.

Edited July 31, 2023 by BigRedX

[alexa3020]

Presumably when FOH take a line from your amp, they are just eq-ing the signal to sound like it's running through a cab. Unless they have cab Sims built in to their equipment - which is probably quite common now

[Bill Fitzmaurice]

That rarely happens. Most sound men make it what they think bass should sound like, and they're usually wrong. My number one complaint about concert sound is pounding deep bass that has no resemblance to what players want for tone, at levels that drown out the rest of the band. 

[JapanAxe]

9 minutes ago, Bill Fitzmaurice said:

That rarely happens. Most sound men make it what they think bass should sound like, and they're usually wrong. My number one complaint about concert sound is pounding deep bass that has no resemblance to what players want for tone, at levels that drown out the rest of the band. 

Tell me about it! I played a big festival last year and every note on my bass, from C on the A string down, was accompanied by an earth-shaking WHUMPH through the PA. It felt quite embarrassing and made it hard to play in time.

[Dan Dare]

1 hour ago, JapanAxe said:

Tell me about it! I played a big festival last year and every note on my bass, from C on the A string down, was accompanied by an earth-shaking WHUMPH through the PA. It felt quite embarrassing and made it hard to play in time.

 

I feel your pain, although tbf, you wouldn't have been hearing what the person mixing was. All you would have got from your position behind the main FOH speakers would have been low bass. I know that many "engineers" do emphasise the "wump" because, as Bill points out, they think that's what bass should sound like (probably because the heavily compressed and artificial bass on the records they listen to does), but it may not have been as bad out front with the higher frequencies (which are more directional and wouldn't have made it back to you) included. Then again, I may be being too charitable to the person mixing...

[Bill Fitzmaurice]

The main problem is PA subs that go an octave lower than bass cabs. The cure is to high pass the bass channel strip around 60Hz. FOH guys who are also bass players or recording engineers known this. But those who aren't usually don't.

[LukeFRC]

12 hours ago, fretmeister said:

Partly. A speaker is effectively a really complex EQ curve.

 

But a speaker is not a static EQ curve - it changes depending on what is feeding it. So an EQ with enough bands / parametric can get you close it will never be exactly the same.

 

The image below is one that bass nerd Jon Willis made showing his best shot at duplicating an Ampeg 810 (old one and modern) using an EQ. He did it in the Helix to get the freqs right. I use it quite a bit with my Helix.

 

Jon is really god at this sort of thing - he even helped Billy Sheehan set up his current Helix based rig.

 

 

 

though interestingly these aren't IR's ... they literally are EQ curves....

 

 

I bought a multiFX pedal (Zoom B3, then Zoom B3n then HXstomp) mainly as I played at a church and odd things would happen on the digital desk. Part of my way of solving this was to give them a signal that approximated the response of a bass cab with the top and bottom trimmed... 

 

The Zoom things were really nice, but the HXstomp got into IRs and... I tried them for a long time but couldn't make them work for me. 
To my ears IR's sound amazing on electric guitar and do lovely things to the tone. The HX stomp is utterly amazing on electric. 
For bass though the sound of a speaker cab recorded through a mic just felt odd, like there was a blanket thrown over something, or some thing in the phase in the mids or there was latentency I was playing against or something (NB I have no idea what it was) - and I always preferred using no IR or cab sim and just a HPF, LPF. 

@warwickhunt - you would be able to test it, if you load a blank IR into your NUX and just use the HPF/LPF on the editor