In this article, we describe an improvement of the ultrasonic aerosol generator published by Pokharel et al. (Aerosol Science and Technology 53(3): 321-331) to extend the aerosol number concentration achievable from-6 x 10(3)#/cm(-3)to >10(7) #/cm(-3) from commercially available TiO2 powder. We demonstrate the scalability of the ultrasonic aerosol generation by using multiple ultrasonic transducers to increase the stability and concentration of the aerosol output. Using three ultrasonic transducers, aerosol concentrations in the range of similar to 10(7) #/cm(-3) from raw TiO2 powder and similar to 10(7)-10(8) #/cm(-3). for milled powder were generated. The mass concentration of particles >0.3 mu m is of the order of similar to 500mg/m(-3). The superior dispersibility of the milled powder compared to raw powder is explained based on the coating of ultrafine particles on the surface of fine and coarse powder particles. The condusions derived herein are supported with upper bound estimates of number concentration and size distribution of aerosols. (C) 2020 Elsevier B.V. All rights reserved.