## 5 Conclusions and Outlook  
The investigations conducted in this study showed that the torque-dependent tire noise in the vehicle interior has a significant influence on the perceptibility of tonal powertrain noise, as already shown in previous studies [13; 31; 32; 33]. The main contributions to this effect can be attributed to the first and second block harmonic on the one hand and to high-frequency noise components due to slippage in the contact patch of the tire on the other hand. By using regression polynomials to model the torque influence on the tire noise components and subsequently combining the derived correction factors with frequency- and rpm-dependent weighting functions, a valid correction factor map could be derived. By applying the method, the error that is made when only considering one torque level can be reduced over the entire order range that typically occurs in electric vehicles.  
Due to the goal of a generalized method, the considered parameters were minimized. However, there are more effects that contribute to the torque dependency of the masking threshold that were not considered in this study. On the one hand, the considered measurements were conducted with rear-wheel drive vehicles only. Additional effects caused by all-wheel drive vehicles, such as the interaction of differing noise phenomena from both axels, varying torque distribution between the axels or differing transfer paths between RWD and AWD are thus not considered in the derived calculation method and offer potential for further development. On the other hand, the tire itself is a critical factor, as it can substantially affect the torque dependency of the tire noise. By considering the technical data of the tire, this method can be optimized. Environmental factors, such as temperature and humidity, can also have an effect on tire noise. Further investigations on the influence of environmental factors on torque dependency can be made in the future.  
In the next step, this method can be adjusted to road measurements, where additional effects need to be considered. Besides noise interference such as cracking noises at high torque levels on the road, the interference with aerodynamic noises can be considered in the future.  
Conceptualization, V.A. and C.M.; methodology, V.A. and C.M.; software, V.A. and C.M.; validation, V.A.; writing--original draft preparation, V.A.; writing--review and editing, C.M., D.L. and M.E.A.; visualization, V.A.; supervision, D.L. and M.E.A.; All authors have read and agreed to the published version of the manuscript.  
This research received no external funding.  
The data is not publicly available due to confidentiality requirements of the company.  
Authors [PERSON], [PERSON] and [PERSON] were employed by the company Mercedes-Benz AG during the preparation of this study. The company had no role in the design of the study, in the collection, analyses, or interpretation of data, in the writing of the manuscript, and in the decision to publish the results. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.