I have a technical question. I’d like to fully understand how the FFB output by AMS2 actually works: the value sent to the wheelbase at any given moment, is it a real force percentage, or is it a specific force value? Let me explain it another way. Suppose I drive the same car on the same section of track (a straight, for example) with a 23 Nm wheelbase, and then do exactly the same thing with an 8 Nm wheelbase. We’ll assume that we don't change any of the gain parameters, either in the game or in the wheelbase. Imagine that at a particular moment I hit a big bump. Option A: If what AMS2 sends to the wheelbase is a percentage of force (let's say 20% in that particular situation and 100% when I hit the bump), then what I feel on the 23 Nm wheelbase is much stronger than on the 8 Nm one ALWAYS. The bump would feel "proportionally the same" on both bases (on the 23 Nm one it would try to break my wrists, obviously I'm exaggerating, but you get the idea). Option B: If what AMS2 sends to the wheelbase is an actual force value (let's say 3 Nm in that particular situation and 15 Nm when I hit the bump), then what I feel on the 23 Nm wheelbase is exactly the same as on the 8 Nm one. When the bump hits, the 8 Nm wheelbase clips because it can't produce 15 Nm, so a 15 Nm bump would feel the same as a 10 Nm bump, since both would hit the maximum output. Meanwhile, the 23 Nm wheelbase would actually give me those 15 Nm, and if it were a 10 Nm bump it would feel softer, while a 20 Nm bump would feel stronger. From my point of view, option B is the correct and realistic one. It also allows each car to have its own "force range". But something tells me that in reality it's actually option A, which would mean that, taken to the extreme, if I had a hypothetical 100 Nm wheelbase, the car would be undriveable without some serious gym training.
An analogy: Playing a digital audio source through an amplifier and speaker. If your digital audio source at a specific point in time is playing back a signal with amplitude -18 dBFS, the amplifier will convert that digital audio signal to electroacoustic energy, for example at -24 dBV. The speaker will then convert that to sound pressure, for example at 80 dB SPL. In this scenario, there is no way for the digital audio source to know what sound pressure the speaker will produce, it all depends on the strength of the amplifier (i.e. the strength of the motor in the wheelbase). And if you swap the amplifier/wheelbase to another with a different strength, you get a different strength at the output. In the audio world, there are calibration standards, for example Dolby/THX and SMPTE RP 200 where -20 dBFS is matched to 85 dB SPL. In the racing sim force feedback world, there are no such calibration standards. It's all a question of normalizing signals in order to reduce the noise floor and prevent clipping, and then match the output strength to taste.
Thank you so much for the explanation. It really surprises me that it works this way. In my head, it should work the other way around. In other words, paying for more Nm should give me more subtlety and more range in the details, but as far as normal behaviour is concerned, to me it should be the same regardless of the wheelbase. For example, if an old car doesn't have power steering, it should feel heavier than a modern car that does, regardless of how many Nm my wheelbase has. Otherwise, as I said in my exaggerated example, if we had 100 Nm wheelbases, the car would be undriveable without changing anything. Whereas, at least in my mind, it should feel the same as using a 20 Nm wheelbase. In any case, I understand now. Thanks again for the explanation!
When I upgraded from a Moza R9 V1 to the R12 V2 I had to drop the FFB force by about 10 points to get it feeling about the same. But it doesn't make sense to have the game provide a fixed amount of torque, because then you suddenly need to accommodate for the people using a Logitech G25, and the people using a 23Nm base. Much better to use a proportion of a maximum signal and let the "amplifier" as per Roar's example, do the signal boosting it's designed to do.
I don't see it that way. To me, what makes sense is for each car to deliver the amount of force that reflects the reality of that car. So a car with very light steering shouldn't need much force, while a car without power steering should leave your arms aching. That's the reality of the car, and that's what my simulator should reproduce. There shouldn't be any need to normalize everything to the same baseline. The wheelbases should simply "do what they can": if the car needs to deliver 3 Nm and your wheelbase can do it, great. If it can't, you get clipping. With another car, if it needs to deliver 12 Nm and your wheelbase can do it, great. If it can't, you get clipping. At least that's how I understand what a simulator should do: simulate reality as faithfully as possible.
But AMS2 does do this just as a percentage. If you drive the big trucks the steering is so much lighter than say the go-karts. I have a DD2 and have found values I like and then just leave all my settings, on the wheel and in game alone. Steering angle is set to auto, and force set so that a GT3 hitting kerbs peaks at about 15Nm, and it's great feeling the difference between all the vehicles in AMS2.
