What is the difference between a Shure FP24 and a Sound Devices MixPre?
Originally, the products were identical. In October 2002, Sound Devices made several changes to the MixPre. These are detailed in the following bulletin on the Sound Devices website:
Include were a change in the output meter LEDs, a change to the input DC connector, and a change in the output signal configuration; specifically, the output signal configuration was changed from "impedance balanced" to "active balanced". The differences between these two configurations are noted here:
The single issue that prompted this change is that certain specific Sony camcorders,like the PD150, "do not properly accept any audio signals from impedance-balanced outputs". For these cameras, Sound Devices supplied an accessory cable (XL-55) that padded down the line-level signal from the MixPre to mic-level and then unbalanced the signal in a suitable manner, due to the fact that the "impedance balanced" output only has signal on Pin 2.
The result is that the Shure FP24 and the Sound Devices MixPre are no longer the same product and have not been since October 2002.