Confused about cab sims

[Oomo]

I've never really tried any seriously (I've quickly tried some software ones, and they just made everything sound wooly/muffled), and confused about what they're for or how they work.

 

If you've got a 1x8 speaker and run a 4x10 cab sim into it, it can't possibly sound like a real 4x10 - so what am I missing?

 

Are they just something you'd maybe use for recording direct rather than for live sound? Or are they more like some EQ presets which are applied to get familiar sounds conveniently?

 

 

[bobbass4k]

They're intended for running direct into a recording interface or a desk, as part of a DI setup, which is why many of them integrate an XLR output for DI. They're also becoming very popular for home practice, there's a lot of models now with integrated headphone amps and outputs. 

 

It's amazing how many people don't really understand what a necessity they are, especially if you're using pedals. Pedals are, by and large, designed and tested with an amp and cab setup. Cabs have a huge impact on the the sound in terms of what frequencies are present and how they respond, so if you just plug a distortion pedal directly into an interface, you're not hearing it as it was designed to be heard, and in all likelihood it will sound absolutely terrible. Even if you're running a preamp or a DI box, cab simulation is a crucial stage of the process to get to how it was designed to be heard. Many modern cab sims will also include power amp simulation, so along with a preamp pedal you can have a complete setup.

 

Many of the early pedal ones were just very specific EQs that did a passable job, but the modern approach is something called Impulse Response loading (IR) - the physics is kind of complicated but basically they can digitally "sample" the way real cabs, mics and power amps affect the sound going through them, as an impulse response file. These are then loaded into software in the pedals (or a plug-in) and applied digitally to your signal, emulating the way it would respond. Most major cab and amp manufacturers now sell IR files for their cabs, that are compatible with basically any IR pedal. It's only in the last 6 or 7 years that the DSP (Digital Signal Processing) technology required to do this has become affordable and mass market enough to enable this - the Mooer radar costs about £100 and does a good job with limited features (no DI out).

[MrDinsdale]

You can also run from a cab sim into a monitor/flat response speaker rather that a traditional bass amp/cab for a super portable option.

[Oomo]

Thanks, that makes a ton of sense now.

 

So sounds like something you'd use any time you're not using an actual physical amp - direct into house PA, headphone practice at home, recording direct etc.

 

The IR thing is a lot clearer too - rather than being just a set of EQ applied uniformly, sounds like something more dynamic that responds to input.

[fretmeister]

Don’t stack speakers into more speakers.

 

A mic’d speaker doesn’t need a cab sim / IR.

 

Go direct into the interface instead. Then you can record a bare tone and change amps and cabs after.

[jimfist]

2 hours ago, Oomo said:

The IR thing is a lot clearer too - rather than being just a set of EQ applied uniformly, sounds like something more dynamic that responds to input.

 

Yes, except for the part about the IR itself responding to dynamic input. This is not the case.

A cabinet IR is nothing more than a tonal overlay filter - a complex EQ footprint, digitally captured as a .wav file, to be used by digital processors that implement IR (player) technology.

 

There may be devices that use the cab IR as an EQ/filter component of a broader cabinet simulation process that is dynamic, but by itself the IR is not a dynamic element.

The dynamic elements that help really bring a speaker system (guitar or bass amp) to life can happen between the (tube) head and the physical speaker.

For that reason, there are now "load boxes" with IR technology, designed to capture this dynamic interaction, but replacing the real-world mic'ing of the speaker with the cab IR.

 

Fractal Audio Systems - in particular their latest flagship products AxeFXIII and FM9 - has made tremendous strides in modeling the entire 'preamp - power amp - speaker cabinet/IR' signal chain interactivity, to the point where it is scary close to what you get sonically using real-world gear.

10 years ago, not many bassists were much interested in going the cab IR route, but as the technology and quality improves, we're seeing more and more jump on the bandwagon.

[Downunderwonder]

4 hours ago, fretmeister said:

A mic’d speaker doesn’t need a cab sim / IR

Depends on the speaker and the volume level.

 

You can plug a sim in and play through a FRFR cab and get the desired tone at low stage volume, although in that case it likely wouldn't be mic'd, but the idea holds for home use and recording, without a sim you won't get the A-Z tones out of the FRFR cab and you're stuck with the tones of any other cab at the volume level you can have.

[fretmeister]

12 hours ago, Downunderwonder said:

Depends on the speaker and the volume level.

 

You can plug a sim in and play through a FRFR cab and get the desired tone at low stage volume, although in that case it likely wouldn't be mic'd, but the idea holds for home use and recording, without a sim you won't get the A-Z tones out of the FRFR cab and you're stuck with the tones of any other cab at the volume level you can have.

 

 

Ok.

 

A mic'd traditional bass speaker does not need a cab sim or IR.

[fretmeister]

Also worth remembering that some of the greatest bass tones in history were bass direct into the board with a good compressor like a '76. No cabs, no amps.

 

The Dr Tone Secret Bass lab has a page with EQ settings to be used in place of cab sims and they are excellent.

[Downunderwonder]

8 minutes ago, fretmeister said:

 

 

Ok.

 

A mic'd traditional bass speaker does not need a cab sim or IR.

But it needs all the other cabs and mics you like to be on standby.

[BigRedX]

I've completely given up on cab sims when using my Helix. IME all bass cabs are a compromise that muck up your sound and in a conventional rig a good bit of your amp EQ settings are there to overcome the limitations of the cabs. Most of the time the cabs are basically low pass filters so simply rolling off the very high frequencies will do the trick. The best thing about this method is that you can use your ears to get the sound you want and you are not fighting against ancient "technology". I've also ditched most of my amp sims too, as again an amp is simply a set of EQ controls with a baked-in sound when they are set "flat". The only amp sims I use now are there for their distortion sounds.

 

Edit: as has been said many of the great recorded bass sounds are simply studio EQ and compression and no amps or cabs were used in the process.

Edited May 30, 2022 by BigRedX

[jimfist]

There are many in agreement regarding using pure DI + EQ + COMP at the mixing desk for bass tone.

No doubt this has been done for decades and continues to be done.

Cabinet IR technology is just another tool for those who wish to use it, and there are many reasons why one would want to consider it.

 

I can't count how many discussions there have been weighing 'mic'd cabinet' vs. 'DI', or a combination of both, as a means to get their bass sound to a mixing desk.

IR technology simply merges the two techniques so you can have a mic'd cabinet in a DI form that is extremely versatile and practical.

 

Like it...or not.  Use it....or not.