Understanding amps and IR's?

So I'm still getting into learning about how IR's work even though I clearly hear a difference when changing it with whatever amp I use. An Impulse response captures the sound of the speaker in relation to the mic and environment it is captured in.

But does the amp model affect the end result of the IR? I often see IR's named like 1x12 65 Deluxe Reverb. If it was a different year amp (1968 for example) running through the exact same speaker,cab,mic etc, would that effect the end capture of the 1x12? Sorry if its a stupid question, I'm genuinely curious how the specific amp chassis affects the speaker capture.
 
The name is giving you an indication of the cabinet / speaker the IR was captured from.

The amp is not involved in the IR capture.
 
Typically, IRs are captured in such a way that the driving amplifier is taken out of the equation as much as possible. Usually either a separate clean, flat response amplifier is used to drive the cab, or a direct line level tap from the amp output is used to calculate and remove any coloration the amp itself adds. The goal is usually to capture just the response of the cab and speaker, plus any mic coloration and room reflections present.

It's entirely possible a different combo amp would give you a different sound though, even with the exact same speaker. Any differences is cab size, shape, construction, materials, weight, etc. could affect the resonance and response of the cab and speaker package. So, yes it's possible the IR of a 65 Deluxe Reverb 1x12 could sound different than a 68, but not so much because of the amp but rather the construction differences in the cabinets that happened over the years and after CBS started cutting corners.
 
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To get the IR a sinus sweep signal is sent to the Cab and as said, with neutral amp that doesn't color the signal.
And also as already said, every Cab (IR or Physiyal CAB) will sound different, even with same speaker.
If you search, you can find thousands of statements (also here in Froum) that aprox. 50% of total sound is from the cab.
And its true.
If you use the Fractal without CAB sim and your own physical cab, you are more restricted generarting sounds than using FRFR and IRs (cab sim on) or you have to dial in your amp-tone completely different, adapted to your cab to get the sound you want.
Or you can make different amps sound very similar if choosing a cab fitting for the sound you want to get.
There are many users of modelers that want to use their own physical cab because they like the sound of it. Ok thats a way and everybody have his/her own taste and if you want to have the amp in the room sound that you only can get with a appropriate amount of moving air. But you also can get this with cabs built with widerange or fullrange speakers that are near neutral in sound. Thats what I use.
But for me personally it makes no sense to use a normal guitar cab when using a modeler (lousy excepted with bad CAB sim) becasue of restrictions and the fact that not every amp sounds good with every cab.
I use factory IRs or actually IRs from YA Mesa cab but even the IRs of this single cab with several differnt micros on different positions sounds different.
I choose the IRs depending on amp and dialed in tone and also make own mixes of the bought IRs. For example one IR with SM57 mixed with a MD421 and so on.
Thats also the reason why I do not understand that there are still so much guitarists or studio (even stage) technicians that prefer micing a cab instead of using IRs.
Because using different microphones or placements of the mic will change the sound and so its more efford to get the sound you want and stay consistent. And the chance of having problems is bigger (catching unwanted sound with mic, humming, bad or loose stand, defective cables or jacks, and so on...). Escpecially on stage.
But this is my own, personal opinion. May I'm too progressive and modern for a grandpa ;)
 
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