V6 firmware: Time to Release the Monster - Speaker Resonance Page

So my understanding was correct.
Dont you think it would better to model this on the cabinet page instead of tweaking the parameters to to selected cab in the output stage?
The impedance of the the transformer is fairly "linear" - it gets non linear when the speaker comes into the game.
And as every speaker impedance is individual I would have attached it to the cab parameters.

regards
 
alvinlee said:
So my understanding was correct.
Dont you think it would better to model this on the cabinet page instead of tweaking the parameters to to selected cab in the output stage?
The impedance of the the transformer is fairly "linear" - it gets non linear when the speaker comes into the game.
And as every speaker impedance is individual I would have attached it to the cab parameters.

regards
Click to expand...

No, every amp does not react the same to a given cabinet; the interactivity happens in the power amp of the amp. It's not a "speaker" resonance as much as it is a "power amp/speaker" resonance control/setting if you will.
 
Correct.
But also does the same amp not react the same way to different speakers.
I think the impedance curve is more a speaker curve than a amp curve.

Take a tone generator with 200 Ohms in series to an existing cabinet and measure the Voltage over the frequeny (i.e. the impedance) of the cabinet. You will get the curve they model on the amp page.

Try it.
 
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alvinlee said:
Correct.
But also does the same amp not react the same way to different speakers.
I think the impedance curve is more a speaker curve than a amp curve.

Take a tone generator with 200 Ohms in series to an existing cabinet and measure the Voltage over the frequeny (i.e. the impedance) of the cabinet. You will get the curve they model on the amp page.

Try it.
Click to expand...

That was sorta the whole point of the thread. ;)
 
alvinlee said:
Correct.
But also does the same amp not react the same way to different speakers.
I think the impedance curve is more a speaker curve than a amp curve.

Take a tone generator with 200 Ohms in series to an existing cabinet and measure the Voltage over the frequeny (i.e. the impedance) of the cabinet. You will get the curve they model on the amp page.

Try it.
Click to expand...

My assumption on the impedance curve being in the Amp block and not the Cab block (and this is only my assumption with no input or verification from Fractal) is that putting the impedance curve in the Cab block would require the Cab block and Amp block to interact in ways no other blocks interact. Each block operates in a fairly autonomous manner from other blocks - Reverb has no dependencies on Delay, Compressor has no dependencies on PEQ, etc. these block have mono/stereo connections and that's it.

In addition to introducing new interaction between the Amp and Cab blocks the Amp block would be dependent on the Cab block for critical parameters which brings up another issue: How should the Amp block behave if the user chose not to use a Cab block?

Again this is just speculation but I believe the impedance curve is in the Amp block because that's where the data is used.
 
Hi.

very good point - if there is no cab there is no impedance curve like in the amp block. It is the result of an interaction, where suddenly the main partner is ....... missing.
Exactly this case shows that the impedance curve on the amp side is ..... to be discussed.
With a missing cab the amp block could simulate a linear load.

As you know in reality a tube amp without a load....

Good point!
 
The bottom line for me is,

It would be killer if the impedance data matching the cab IR's was readily available and easy to program.

I would trust FAS to figure out what block or blocks to make that happen :)
 
How would you simulate an output transformer interacting with the speaker if you use a SS amplifier and a real cab? There's no CAB block in the grid, so it is the right place for this setting being in the amp block.
 
Im sorry, but I think you didnt get the point. This is exactly what I wrote: the speaker impedance curve ist an interaction between the speaker and the cab. If you model it within the amp model and the speaker is missing - this is no longer the right impedance curve ( in reality this is exactly what you dont do to avoid tube damage).
So if you take this amp model and connect it to a high impedance input (the input of another output stage) there is an impedance mismatching because the input is no low impedance non linear speaker but a high impedance input.
I am not even shure what would happen in reality if you connect a speaker output to an input stage of another amp ( the output transformer is there to transform (= match) the low impedance of a speaker to the high impedance output of the power stage).

This is exactly why the non linear impedance curve has to be inside the speaker block - if there is no speaker the curve is completely different (maybe even linear)

If you really want to model the behavior of a real tube amp I think you should not leave the cab - in the real world this is not possible either.

Regards
 
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I use AxeFX->Matrix->2x12 cab. How would I have the real tube amp hooked to a cab sound if that parameter would be in the CAB block? It's really not a good idea to run a CAB block and then use a real cab. That's the magic of the AxeFX, you can do things that would not be possible in the analogue tube world.
 
alvinlee said:
Im sorry, but I think you didnt get the point is exactly what I wrote: the speaker impedance curve ist an interaction between the speaker and the cab. If you model it within the amp model and the speaker is missing - this is no longer the right impedance curve ( in reality this is exactly what you dont do to avoid tube damage).
So if you take this amp model and connect it to a high impedance input (the input of another output stage) there is an impedance mismatching because the input is no low impedance non linear speaker but a high impedance input.
I am not even shure what would happen in reality if you connect a speaker output to an input stage of another amp ( the output transformer is there to transform (= match) the low impedance of a speaker to the high impedance output of the power stage).

This is exactly why the non linear impedance curve has to be inside the speaker block - if there is no speaker the curve is completely different (maybe even linear)

If you really want to model the behavior of a real tube amp I think you should not leave the cab - in the real world this is not possible either.

Regards
Click to expand...

If you use the search function and look for a reply by Cliff regarding this you will get the answers and can stop the speculations!
 
jeppekristoffer said:
If you use the search function and look for a reply by Cliff regarding this you will get the answers and can stop the speculations!
Click to expand...

Wow, this post really helps.

Didnt know that the university professors have been telling us only speculations.

Thanks, now I know.
 
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Chill out, man. You sound like a bunch of guys arguing over whether pirates or ninjas are better.

Go take a dump, take a nap, eat some pop tarts and play outside for a while.
 
alvinlee said:
Wow, this post really helps.

Didnt know that the university professors have been telling us only speculations.

Thanks, now I know.
Click to expand...

What a lovely attitude :) While your points may make sense for the actual behaviour of the physical amps and cabs, they may not be directly relevant to the way things are implemented in the Axe. So yes, unless you actually know how the modelled firmware handles this, it is indeed speculation.

I'm quite confident the man himself is fully aware of how this works, and has perfectly valid reasons for setting it up the way he does.
 
alvinlee said:
Wow, this post really helps.

Didnt know that the university professors have been telling us only speculations.

Thanks, now I know.
Click to expand...

Ok. Sorry I didn't mean to offend you or anyone else. Was just trying to help to clear some questions but maybe expressed myself a little but clumpsy while trying to give a tip on what I use to do when I have questions. I try to search for Cliffs opinions on the subject since he is the brain behind the Axe.
 
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