Replacing IR Cab Sim for EQ

[Ritter667]

So I utilize an "amp-less" setup, and normally I use a NUX Melvin Lee Davis Bass Premap + DI, that both is capable of emulating various amps and has build in IR loader.

Personally I use the Aguilar Tone Hammer amp emulation, and the IR based Ampeg SVT212AV cab sim.

But I then decided to try out replacing it for EQ alone, using a Zoom MS-70CDR as a 12 band parametric equalizer by loading the 2 band fully parametric Bass Para EQ model in each available slot of a patch on the pedal, and I managed, through a lot of experimenting to dial in a tone that is much clearer and articulated than what I got from the NUX.

I realize I am missing out on the IR sims dynamic frequency response, but to me the pure EQ sounds better.

So does anyone else use EQ in place of cab sims?

 

[Wasnex]

My advice, if you like the EQ better, use the EQ. There is no right answer; only what is right for you.

I use EQ and I don't see much point in using a cab SIM. But I prefer more of a HiFi, full-range sound. Some people prefer the tone of a heavily-voiced bass rig. For these people a good cab SIM could be useful. Or it could get in the way, if use incorrectly.

 

[coyoteboy]

Im curious about your settings. Never considered making a super-eq with my zooms.

 

[Ritter667]

Im curious about your settings. Never considered making a super-eq with my zooms.

My settings are as follows, mind I like my tone being mid heavy:

Freq: 20Hz - Q: 0.5 - dB: - 20
Freq: 40Hz - Q: 2 - dB: + 12
Freq: 100Hz - Q: 4 - dB: + 4
Freq: 140Hz - Q: 4 - dB: - 2
Freq: 200Hz - Q: 4 - dB: - 3
Freq: 350Hz - Q: 1 - dB: + 7
Freq: 1kHz - Q: 4 - dB: + 3
Freq: 2.5kHz - Q: 4 - dB: - 3
Freq: 3.6kHz - Q: 2 - dB: +3
Freq: 12kHz - Q: 1 - dB: - 12
Freq: 16kHz - Q: 1 - dB: - 20
Freq: 20kHz - Q: 0.5 - dB: - 20

The combined 3 upper bands creating a faux, but effective, LPF, with the -3dB cutting point at about 4/4.5kHz or so.

Additionally I have a tube preamp come right after the Zoom makeshift 12 band parametric EQ, with a build in HPF, fixed at 40Hz, activated.

That combined results is a frequency response/EQ curve that looks something like this:

Now on that graph It does look like a bit of a drastic EQ curve, but keep in mind the dB range of the graph (it was what I happened to have at my hands that could illustrate the frequency response), which only goes to about +/- 12dB.

It is not modeled after any specific cab/speaker's frequency response, I just used my ears, the HP and LP though are fairly typical of bass speakers/cabinets without a high frequency horn.

 

[coyoteboy]

Thats great, thanks!

 

[Ritter667]

My settings are as follows, mind I like my tone being mid heavy:

Freq: 20Hz - Q: 0.5 - dB: - 20
Freq: 40Hz - Q: 2 - dB: + 12
Freq: 100Hz - Q: 4 - dB: + 4
Freq: 140Hz - Q: 4 - dB: - 2
Freq: 200Hz - Q: 4 - dB: - 3
Freq: 350Hz - Q: 1 - dB: + 7
Freq: 1kHz - Q: 4 - dB: + 3
Freq: 2.5kHz - Q: 4 - dB: - 3
Freq: 3.6kHz - Q: 2 - dB: +3
Freq: 12kHz - Q: 1 - dB: - 12
Freq: 16kHz - Q: 1 - dB: - 20
Freq: 20kHz - Q: 0.5 - dB: - 20

The combined 3 upper bands creating a faux, but effective, LPF, with the -3dB cutting point at about 4/4.5kHz or so.

Additionally I have a tube preamp come right after the Zoom makeshift 12 band parametric EQ, with a build in HPF, fixed at 40Hz, activated.

That combined results is a frequency response/EQ curve that looks something like this:
View attachment 7350728

Now on that graph It does look like a bit of a drastic EQ curve, but keep in mind the dB range of the graph (it was what I happened to have at my hands that could illustrate the frequency response), which only goes to about +/- 12dB.

It is not modeled after any specific cab/speaker's frequency response, I just used my ears, the HP and LP though are fairly typical of bass speakers/cabinets without a high frequency horn.

So I started experimenting with cutting away EQ points, since admittedly the first one here was all build around that pretty substantial mid boost around 350Hz, and what I surprisingly found was that is sounded much better just using these points:

Freq: 20Hz - Q: 0.5 - dB: - 20
Freq: 40Hz - Q: 2 - dB: + 12
Freq: 1kHz - Q: 4 - dB: + 3
Freq: 1.2kHz - Q: 4 - dB: +1
Freq: 3.6kHz - Q: 2 - dB: +3
Freq: 12kHz - Q: 1 - dB: - 12
Freq: 16kHz - Q: 1 - dB: - 20
Freq: 20kHz - Q: 0.5 - dB: - 20

8 bands total, which means I can get away with just using 4 slots on the pedal, which also means that this would be viable on something like a Zoom B1(X)on.

Graphically, including the following 40Hz HPF, looking something like this:

 

[blr2]

IR response captures more than just the eq of a mic'ed cab. It also gives you the cab distortion and harmonic content. It is more faithful representation of the real cab, but if you only want the general tone, an eq will be ok. Before I had a good cab sim, I used 31 band eq and it worked.

 

[Ritter667]

IR response captures more than just the eq of a mic'ed cab. It also gives you the cab distortion and harmonic content. It is more faithful representation of the real cab, but if you only want the general tone, an eq will be ok. Before I had a good cab sim, I used 31 band eq and it worked.

I do realize that, and I actually mentioned it too in the OP, how the frequency response of an IR based cab sim reacts dynamically to the input.

Non the less I prefer the EQ method, and I tried a lot of IR based cab sims.

I guess I am not really all that interested in simulating a cab, as much as I am just interested in sounding great.

 

[blr2]

I do realize that, and I actually mentioned it too in the OP, how the frequency response of an IR based cab sim reacts dynamically to the input.

Non the less I prefer the EQ method, and I tried a lot of IR based cab sims.

I guess I am not really all that interested in simulating a cab, as much as I am just interested in sounding great.

Nothing wrong with that. Some people prefer the cleaner tone of the eq (or even run a flat DI straight to the full range PA speakers). There are also analog cab sims that use inductors to simulate a cab, I like these too.

 

[Ritter667]

Well...

That didn't last long...

I am back to my amp emulator/cab simulator pedal.

What infatuated me about the EQ solution was the clarity, but I missed the dynamics and depth of my amp emulator/cab sim pedal.

Definitely not as clear and sparkling as the EQ solution, but on the other hand considerably more depth and heft to it.

But at least now I have myself a viable emergency backup solution, should my amp/cab pedal fail.

 

[blr2]

Definitely not as clear and sparkling as the EQ solution, but on the other hand considerably more depth and heft to it.

Perhaps, you can choose another IR response from a brighter/cleaner cab. There many options.

 

[PhR75]

I've been recently using a cab sim that has the low end from DI and high end from a cab simulation (cut off point circa 300hz). A friend made it for me.
I find the low end easier to deal with. For example easier to boost the bass if needed (I use the same NUX MLD preamp) and it still has the qualities of the cab sound (which I prefer to the straight DI sound).

I wish there was a preamp with a blend or a crossover for DI and IR. As handy as a separate tone or LPF for clean sound on an overdrive pedal (which is also usually missing).

 

[blr2]

I wish there was a preamp with a blend or a crossover for DI and IR.

When blending digitally processed and analog path signals, one should be careful to keep them phase aligned. Digital signals usually have (however small) latency. Although it may not be audible, it causes phase shifts.

 

[6thplanet]

I was gonna suggest running the EQ parallel with the amp/cab model, being mindful of phase/delay issues.

 

[Ritter667]

So I started experimenting with cutting away EQ points, since admittedly the first one here was all build around that pretty substantial mid boost around 350Hz, and what I surprisingly found was that is sounded much better just using these points:

Freq: 20Hz - Q: 0.5 - dB: - 20
Freq: 40Hz - Q: 2 - dB: + 12
Freq: 1kHz - Q: 4 - dB: + 3
Freq: 1.2kHz - Q: 4 - dB: +1
Freq: 3.6kHz - Q: 2 - dB: +3
Freq: 12kHz - Q: 1 - dB: - 12
Freq: 16kHz - Q: 1 - dB: - 20
Freq: 20kHz - Q: 0.5 - dB: - 20

8 bands total, which means I can get away with just using 4 slots on the pedal, which also means that this would be viable on something like a Zoom B1(X)on.

Graphically, including the following 40Hz HPF, looking something like this:
View attachment 7351292

But for those interested in trying out EQ in place of regular cab sim I have another improvement, or at least variation of above, still depending though on the fact that is is followed by a HPF with cut off point at 40Hz:

Freq: 20Hz - Q: 2 - dB: - 20
(Freq: 70Hz - Q: 4 - dB: + 1) [this band can be left out, or boosted more, depending on taste]
Freq: 1kHz - Q: 4 - dB: + 3
Freq: 1.2kHz - Q: 4 - dB: +1
Freq: 3.6kHz - Q: 2 - dB: +3
Freq: 12kHz - Q: 1 - dB: - 12
Freq: 16kHz - Q: 1 - dB: - 20
Freq: 20kHz - Q: 0.5 - dB: - 20

 

[Ritter667]

I've been recently using a cab sim that has the low end from DI and high end from a cab simulation (cut off point circa 300hz). A friend made it for me.
I find the low end easier to deal with. For example easier to boost the bass if needed (I use the same NUX MLD preamp) and it still has the qualities of the cab sound (which I prefer to the straight DI sound).

I wish there was a preamp with a blend or a crossover for DI and IR. As handy as a separate tone or LPF for clean sound on an overdrive pedal (which is also usually missing).

When blending digitally processed and analog path signals, one should be careful to keep them phase aligned. Digital signals usually have (however small) latency. Although it may not be audible, it causes phase shifts.

The manual to the NUX Melvin Lee Davis Bass Preamp + DI states a latency of 1ms.

 

[blr2]

The manual to the NUX Melvin Lee Davis Bass Preamp + DI states a latency of 1ms.

This is more than enough to give you phase issues when blending an analog signal with it. It would be most pronounced in the low end. You won't hear signal delay though.

 

[Ritter667]

This is more than enough to give you phase issues when blending an analog signal with it. It would be most pronounced in the low end. You won't hear signal delay though.

But as with everything, as long as it doesn't damage the equipment, if it sounds good it is good.

 

[blr2]

But as with everything, as long as it doesn't damage the equipment, if it sounds good it is good.

No damage, and if it sounds good to YOU, than it's good.

 

[Wasnex]

This is more than enough to give you phase issues when blending an analog signal with it. It would be most pronounced in the low end. You won't hear signal delay though.

AFAIK at 1mS of delay it will be more mid focused.

Sound travels a bit over 1' in 1mS; 1.13' specifically. You get max cancellation at 180 degrees of phase shift, so 1.13 x 2 = wavelength of 2.26", which equates to about 500hz. In other words if you reinject a signal that is delayed by 1/2 wavelength you get cancellation.

AFAIK you would also get cancellation at higher frequencies as well. This is called comb filtering. Here's what comb filtering looks like on a spectrum analyzer:

You also get peaking that occurs at frequencies where the phase lines back up. Not sure if this image is 100% accurate, but hopefully you get the idea: