You could just shoot an IR of the stationary speaker and apply whatever modulation etc over that. The only difference to running a normal factory cab sim is that you'd be using an IR of the actual speakers that are in a Leslie Cabinet. Thus, tht would help you to better nail the tonal character of the Leslie cabinet. You could even have a separate IR for the drum speaker and the horn speakers if you wanted to get super precise.From what I can tell it’s impractical to create an IR of a spinning Leslie speaker.
Starting with https://wiki.fractalaudio.com/wiki/index.php?title=Impulse_responses_(IR)#IR_length and https://en.wikipedia.org/wiki/Leslie_speaker …
The drum and rotor spin at different speeds whether they’re running fast or slow, so an IR would have to capture up to the point where both speakers crossed their original starting points at the same time otherwise the resulting IR would have a weird artifact. So there’s probably two different versions of the IR…
But it gets even worse because an Impulse Response is a tiny burst of sound that is supposed to occur before echoes in the room can bounce back and be captured. With sound traveling at 1100 feet/second, it’s going to take a big room.
During that process all outside/extraneous sounds need to be ignored by the capturing microphones, because, remember, two spinning speakers need to be captured and they’re driven by two motors, pulleys and belts that can make noise.
And then there’s the differing speeds that other versions and different company’s versions rotate at, and their different cabinet types, and the different ways their amplifiers distort…
And then there’s the needed IRs used to accommodate standard rotations plus speeding up, slowing down, and braking….
I’m not going to do the math because it doesn’t mix well with the couple glasses of wine I had with dinner, but my preliminary checks put it firmly in the nuh-uh range.
Which cabs are you using for the Rotary signal?I don't like the idea of having the Rotary embedded at the CAB Block. If I want a CAB at the Rotary, I set it independent of the main CAB
View attachment 84999
The CAB for the rotary uses two IR in stereo (panned Left and Right)
Yeah I'm hearing you. Could do that. My main jamming improv preset is maxed out for CPU but other song specific presets would have some extra headroom for that to work.If you have enough CPU left, you can use two Rotary blocks one for the Left channel and one for the Right channel and set both parameters the same.
Nope, how else would you get rotary if you play thru a poweramp and cab with the cab sims off.
If I'm reading you right, you're asking why would I run a leslie IR into a Power Amp and Cab. Well ideally you'd be able to use a NULL cab or switch off the Leslie IR if you wanted so it would be no different than how it is currently if that was how you prefer it. Exactly the same as you can do with the Cab block currently.Nope, how else would you get rotary if you play thru a poweramp and cab with the cab sims off?
Which cabs are you using for the Rotary signal?
If I'm reading you right, you're asking why would I run a leslie IR into a Power Amp and Cab.
I'm not going to do the math because it doesn’t mix well with the couple glasses of wine I had with dinner, but my preliminary checks put it firmly in the nuh-uh range.
This is why you don't see Leslie IR files.From what I can tell it’s impractical to create an IR of a spinning Leslie speaker.
Starting with https://wiki.fractalaudio.com/wiki/index.php?title=Impulse_responses_(IR)#IR_length and https://en.wikipedia.org/wiki/Leslie_speaker …
The drum and rotor spin at different speeds whether they’re running fast or slow, so an IR would have to capture up to the point where both speakers crossed their original starting points at the same time otherwise the resulting IR would have a weird artifact. So there’s probably two different versions of the IR…
But it gets even worse because an Impulse Response is a tiny burst of sound that is supposed to occur before echoes in the room can bounce back and be captured. With sound traveling at 1100 feet/second, it’s going to take a big room.
During that process all outside/extraneous sounds need to be ignored by the capturing microphones, because, remember, two spinning speakers need to be captured and they’re driven by two motors, pulleys and belts that can make noise.
And then there’s the differing speeds that other versions and different company’s versions rotate at, and their different cabinet types, and the different ways their amplifiers distort…
And then there’s the needed IRs used to accommodate standard rotations plus speeding up, slowing down, and braking….
I’m not going to do the math because it doesn’t mix well with the couple glasses of wine I had with dinner, but my preliminary checks put it firmly in the nuh-uh range.
The idea is to apply the dopplers while using a single IR. I've had good success implementing that design.This is why you don't see Leslie IR files.
Cycling through 4 or 5 files do not even significantly cover the travel of the upper horn, never mind the travel of the lower horn.
The cycling would also need to be tied to the rate parameter and Crossfade between IR files in order to not have a choppiness to the audio.
It would be memory intensive.
And extremely CPU intensive.It would be memory intensive.
Shouldn’t the drum be 180° out of phase?If you have enough CPU left, you can use two Rotary blocks one for the Left channel and one for the Right channel and set both parameters the same.
Says who?Plenty oy "rotary" pedals out there (which is what the block emulate rather than a true speaker cab)
well, the blocks tend to model pedals where possible (or rack effects). And given the difficulties of modelling a true cab (as discussed) its not likely. I mean, cant be 100% unless cliff chimes in, but taking everything into consideration....Says who?
Easy.... Select a Null cab so you are not using an IR if you are just wanting to use the doppler shifting of the rotary block. Just the same is if you want to use a Leslie IR or any other IR. You select which one you want to use or simply select a Null cab if you don't want to use one. Simple solution.for the OP - in answer to the question - absolutely not. Plenty oy "rotary" pedals out there (which is what the block emulate rather than a true speaker cab) - and how about those of us that dont use cab blocks but still need the effect?
I don't know how anyone got the idea that I was suggesting to shoot an IR of a moving speaker. I was suggesting shooting some IRs of a rotary cabinet (Horn & Drum) whilst the cabinet is stationary. Once you have a good IR of the stationary speakers you can then apply the appropriate doppler shifting for a more authentic Leslie tone. Also the Preamp section in the Cab Block could incorporate the Leslie type to get even closer to the real thing.From what I can tell it’s impractical to create an IR of a spinning Leslie speaker.
Starting with https://wiki.fractalaudio.com/wiki/index.php?title=Impulse_responses_(IR)#IR_length and https://en.wikipedia.org/wiki/Leslie_speaker …
The drum and rotor spin at different speeds whether they’re running fast or slow, so an IR would have to capture up to the point where both speakers crossed their original starting points at the same time otherwise the resulting IR would have a weird artifact. So there’s probably two different versions of the IR…
But it gets even worse because an Impulse Response is a tiny burst of sound that is supposed to occur before echoes in the room can bounce back and be captured. With sound traveling at 1100 feet/second, it’s going to take a big room.
During that process all outside/extraneous sounds need to be ignored by the capturing microphones, because, remember, two spinning speakers need to be captured and they’re driven by two motors, pulleys and belts that can make noise.
And then there’s the differing speeds that other versions and different company’s versions rotate at, and their different cabinet types, and the different ways their amplifiers distort…
And then there’s the needed IRs used to accommodate standard rotations plus speeding up, slowing down, and braking….
I’m not going to do the math because it doesn’t mix well with the couple glasses of wine I had with dinner, but my preliminary checks put it firmly in the nuh-uh range.
Of course I get all that, but I'm just saying that you'd have a better chance of getting a more authentic tone of a real Leslie cabinet by at least using an IR from an actual Leslie cabinet instead of applying rotary simulation to any other random Cab IR.The rotation doesn't just do the Doppler thing. The whole effective response of the horn is different when it's pointed at you vs pointed directly away from you and everywhere in between.
Simulating all of this is non-trivial, and poorly suited to the strengths of IR technology IMO.