The Ortofon Verto uses Lundahl transformers. As Lundahl only makes so many models of transformer for moving coil cartridge applications my money is on that the Verto uses a Lundahl 1941 model. K&K Audio is the American distributor of Lundahl transformers and they have a good write up about them. The K&K Audio premium step up transformer utilizing the 1941 transformers goes for 650$ USD. They are very good.
The Aurorasound SP-03 moving coil step ups use 1931(higher impedance) and 1941(lower impedance) transformers for 24 dB of boost. They go for about 2 grand USD.
For the asking price I don't believe you are going wrong.
The Aurorasound SP-03 moving coil step ups use 1931(higher impedance) and 1941(lower impedance) transformers for 24 dB of boost. They go for about 2 grand USD.
For the asking price I don't believe you are going wrong.