Creating IR guitar cabinet simulation

Hello
I want to get rid of PA microphones in front of my cab. My rig has a class D Poweramp, so I can use the input signal of that amp as a line out, through a impulse loader pedal.

As far as I understand I have to feed an impulse signal to the Poweramp, record the output of the cab. Compare input and output with a convolution plug in, making a impulse response file, which I can load in to my IR loader. Questions:

What impulse signal gives the best, dynamic result. I can imagine that a sine sweep is good to make a freq response/equalisation. But isn’t it better to use a very short burst of noise to nail the dynamic response. Educated guess: block wave 20 Hz (one or two cycles) contains all frequencies, is that suitable?

What plug in is easy to use and gives good results?

I know there is more to it than my short abstract, like normalizing, synchronizing, etc, mic placement, room influences etc

White noise with an abrupt stop. The “impulse” part of the recording is the part immediately after the noise stops.

Alternatively, an up-down pulse with one sample at +1 and the next sample at -1, and all other samples at zero.

The “white noise with abrupt stop” is usually easier to work with.

Hi Steve,
Thank you for your reply!
What do you mean with up-down pulse, is that a block wave at half the sample freq ?
To test an amplifier I use a block wave of somewhere around 400 Hz, but also lower and higher freq. Gives a good impression of the freq response. Have you ever tried a low freq block wave?
I read that some people simply touch a 9 volt battery with the leads of the speaker. I think that is approximately the same as a low freq block wave (?)

Like this:

Hi Steve
Thank you for the recording. Yes I know pulses sound like virtually nothing, because they are so short.

What convolution plug in can you advise, or is it already in the latest version of Audacity?

Cheers
Ger

I know that convolution plug-ins exist but I’ve not used them so I can’t give any recommendations about that.

Nyquist has a convolution function if you want to make your own.