Simucube 2 Pro vs Simucube 2 Ultimate

I also have completely different opinions on the slew rate…It is used to decrease accelerations, accelerations increase as the power of the servo increases.This to me means that a less powerful servo needs less slew rate… If you want to use an ultimate at maximum power I imagine you need more…

Slew rate is a measurements of max motor acceleration, the higher it is the faster motor can change its torque, it’s a physical property of motor and servo controller. The higher it is the faster is that acceleration.
E.g. Sport - 4.8Nm/ms, Pro - 8.0 Nm/ms, Ultimate - 9.5 Nm/ms

Slew rate filter is what is used to slow down that acceleration, you essentially decrease it.
But I understand what you were saying, just a little tidbid to not confuse the actual terms.

All correct, I just didn’t want to spread the idea that it’s the difference in Slew Rate values ​​that make a servo more or less good. And that I personally find different values ​​justified given that they are engines that have different powers and accelerations.

My understanding that this is exactly what makes servo “better”, which is reflected in Simucube current lineup from slowest Nm/ms to the highest one.
Although better is probably not the right term here, as it’s combination of many other things as well.

I personally can’t count it among the strong points for which to spend more or less. Even just talking about the Pro version, if one uses it. 15nm, the mayor is nearby. I don’t think he needs high Slew Rate values.From what I know, the higher the volume, the more the accelerations increase in addition to the forces, So the more you want to play at high volumes, the more natural the steering wheel movement is, you’ll use a higher value.Which is why I believe that the different models have different maximum deceleration values ​​by virtue of the fact that they have different powers. I don’t believe that 9nm/s is needed for a sport used at 17 NM …

We had a discussion on a Slew Rate a while back, while some assumptions in OP were wrong, the bottom line is that higher slew rate allows fuller reconstruction of FFB signal frequencies, if you want to smooth the signal out it’s a different issue.

Slew rate per ms shows the time in ms to reach maximum torque available:
Sport: 17:4.8=3.54ms
Pro: 25:8=3.1ms
Ultimate: 32:9.5=3.36ms

The higher the slew rate per ms the more precise will the depiction of the dynamic change of FFB be. While the difference between Pro and Ultimate is not huge (the difference is more in absolute Nm), the Sport is sure not in the league of the 2 others.
What I don’t know is if these maximum values are occurring/needed a lot, and if the change of slew rate is constant over the time it’s measured. Maybe it’s more in the beginning, I really don’t know.

I read everything and now I’m more confused than before :joy:

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No wonder :rofl:, with so many helpers trying to explain it in different ways, just ignore everything, including max torque calcs above.
In my simple mind it’s just an acceleration rate of the motor, ability to change torque from T1 to T2 value.
Like 0-60 in a sense.
The faster you can do it, the more agile and detailed response would be. Do it slow, and not all details in the signal will make it.

If I understand the process correctly, then we have 3 phases: the speed at which the base receives data from the simulator, the processing speed of the cpu, and slew rate of the motor. This means that a base with a better processor could theoretically be faster or equal to a base with a higher slew rate.

All things equal, it will only impact latency, but I’ll leave this to experts like Mika to explain.

I understand the speed of change of direction,The thing that I don’t like in your explanation is the importance you give to the rotation speed, this is because in the world of Direct Drive and in the simulation it has always been an aspect that in reality has I always tried to slow down to make the steering wheel more natural, but now you’re telling me that it’s important that it’s very fast I knew the slew rate was created precisely to slow down excessive acceleration, In order to make the steering wheel more natural.Fanatec in the dd1 and dd2 models used motors with lightning accelerations But that in my opinion was the problem with their bases…

slew rate being the speed in which the motor can accelerate in a set amount of time, in theory the more nm/ms the faster the response and the more detail is exposed… in theory. hence why the simucube 2 ultimate is the top dog in this lineup of motors, being the fastest motor available.

That said the calculation above is correct. Like Andrew himself wrote: a 0 to 60 thing (not only) but it is. Slew rate is a dynamic value telling how much of a change per millisecond is possible. It ain’t that difficult to understand

I understood what it means to accelerate in a given period of time, But for example, there has always been talk since the days of the sc1 small and big Mige, about the fact that many preferred the Big because in reality it was less reactive, more powerful but less fast than the small. The slew rate slider in true drive, from what I know, is used to decrease the accelerations by a given value… It is one of the most important filters of granite device, With this slider we are going to decrease the accelerations, I don’t understand now why they talk about the more you speed up the better. A different matter for the direction change speed which you imagine has a lot to do with controlling the servo and the signal.

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Lowering slew rate was a revelation for me. Was wondering why almost all Redline drivers have a super low value until I tried it.

Not the speed of response but of acceleration

Again you mix slew rate (motor characterisitc) and slew rate filter (or limit) that allows to slow it down, degrading the motor in a sense.
I personally do not see it as an important feature at all and always use full (max) slew rate. If I need to drop too fast wheel acceleration, Damping is a proper filter for this.
My understanding that in iRacing some users use lower slew rate to avoid harsh spikes that this sim can produce, but with Kunos titles that I mostly use, this never was a problem.
So if you find it useful, by all means use it, it’s just another tool in TD toolbox, same as TBW, I like it at Unlimited to have full scale of the signal, but many would argue that 2000 is all you ever need, or the recon filter, we have folks that swear by at lest 5 to get a realistic feel, I always run it at 1 with AC and ACC.
It’s all subjective, FFB is a car to driver communication tool, I tune it so I can understand it better, loud and clear.

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It’s used to decrease TO a specific value, NOT BY a specific value.
Slew rate filter off=full slew rate available
Slew rate filter set to 0.1/0.2 Aso= slew rate is at 0.1/0.2Nm per millisecond.

If a title, a car in a title has very fast and massive changes in the FFB signal, then the torque applied from the wheel, together with the wheel’s ability on how much it can change the amount of torque from point a to point b per millisecond decides if the wheel can depicts what was the intention of the developer, how harsh a collision can be, how rough kerbs can feel.
Maybe this is helpful:

Exactly at the time of sc1 there was a lot of talk about the excessive speed of these engines,Decreasing acceleration makes driving more natural, which many then mistake excessive reactivity for more detail I find this to be a very personal aspect.I also use slew rate values ​​on other titles, which reduce speed, This is because I seem to have more natural reactions Personally I was a very satisfied user of sc1, but precisely because of the slew rate and sfr filter,Upon leaving, I decided to buy sc2 because they were going to solve two problems that were talked about at the time. I’ll tell you for example that I entered the closed beta of rennsport,Personally, it’s a game that’s starting to make these filters useless, It is very well studied in terms of forces and their distribution.

Then this would be a title that catches up from game side, finally a game focusing on today’s hardware! @Andrew_WOT disagrees with me on almost everything, surprisingly we have almost identical settings: recon one, bandwidth unlimited, no slew rate limitation, a little bit of damping and me a little bit of friction. I prefer to reduce overall torque before I reduce slew rate, but this is also because I have a Sport R2.
We should also not forget that the difference between a GT car in ACC, and the same car in RF2, can be massive.
Based on the overall gain we have set in-game our torque amount in TD can also be very different.