speaker impedance curve selection w different cabs

[roodboy]

if using a 4x 12 with greenbacks and another 4x12 with say v30s what is the right impedance curve to use?
I know use your ears is the inevitable response but is there a correct answer objectively?

 

[Greg Ferguson]

No, not really. You can set whichever you want, or average the settings for the two. The automatic Speaker Impedance Curve will track whichever speaker is selected for the first IR in the Cab block.

Also, I have a preset where I used a deliberate mismatch: the speaker was custom-made by one brand to sound like another brand’s speaker. I used the IR for the first and the SIC of the second and it sounds extremely close to the real amp.

https://wiki.fractalaudio.com/wiki/index.php?title=Amp_block#SPEAKER_IMPEDANCE_CURVE has Cliff’s comments.

 

[Countryclarke]

No, not really. You can set whichever you want, or average the settings for the two. The automatic Speaker Impedance Curve will track whichever speaker is selected for the first IR in the Cab block.

Also, I have a preset where I used a deliberate mismatch: the speaker was custom-made by one brand to sound like another brand’s speaker. I used the IR for the first and the SIC of the second and it sounds extremely close to the real amp.

https://wiki.fractalaudio.com/wiki/index.php?title=Amp_block#SPEAKER_IMPEDANCE_CURVE has Cliff’s comments.

I thought the auto SIC only worked with the dynacabs? At least thats how I interpreted it.


Random question - why does the 4x12 USA MC90 SIC make everything sound better (also louder)?

 

[Greg Ferguson]

I thought the auto SIC only worked with the dynacabs? At least thats how I interpreted it.

Yes, only Dyna-Cabs for the auto selection.

 

[Countryclarke]

Yes, only Dyna-Cabs for the auto selection.

So you're comment about -

The automatic Speaker Impedance Curve will track whichever speaker is selected for the first IR in the Cab block

Is only applicable when using a DynaCab?

Not trying to call you our or anything here, genuinely want to clarify for myself.

 

[Greg Ferguson]

The automatic Speaker Impedance Curve will track whichever speaker is selected for the first IR in the Cab block.

Is only applicable when using a DynaCab?

Again, yes.

Here it is straight from the man:

[28] The Amp block now features “Auto Dyna-Cab Impedance”. When set to ON the speaker impedance curve of the Amp block will follow the Cabinet Type in the first mixer slot of the associated Cabinet block. I.e., if the Cab Type in the first mixer slot of Cabinet 1 is, say, 4x12 5153 and the Mode is Dyna- Cab then Amp 1’s speaker impedance will automatically be set to 4x12 5153.

 

[Countryclarke]

Again, yes.

Here it is straight from the man:

Its not very clear when you say it works for "the first IR in the cab block". I would consider that incorrect information.

 

[Greg Ferguson]

Its not very clear when you say it works for "the first IR in the cab block". I would consider that incorrect information.

Dyna-Cabs are IRs, they're just bundled into a proprietary package.

I'm sure you can figure out what was meant and work around any inadequacies in my comment.

 

[Countryclarke]

Dyna-Cabs are IRs, they're just bundled into a proprietary package.

I'm sure you can figure out what was meant and work around any inadequacies in my comment.

All Dynacabs may be IRs, but not all IRs are Dynacabs.
I was simply asking for clarity, because what you were saying seemed to be conflicting.
Thanks for the help.

 

[greiswig]

Its not very clear when you say it works for "the first IR in the cab block". I would consider that incorrect information.

He means that whatever channel in the cab block is selected, there are two slots. Whichever IR is in the first slot determines the SIC if the channel is using Dyna-Cab, unless you override that.

 

[icarri]

Random question - why does the 4x12 USA MC90 SIC make everything sound better (also louder)?

I wonder the same and recently wrote about it here: https://forum.fractalaudio.com/threads/4x12-usa-mc90-dynacab-uniqueness.209454/

There must be something in the EQ curve making it sound louder and more clear (more mids??) but can’t figure out what as my ears are not trained enough and the FM3 doesn’t have an analyzer built in like the fx3.