Hi,
I too have had this combination. Although the PH5 is listed as having the same amound of gain as the PH7, the PH5 does not work well with very low output cartriages. What I did to over come this problem was to install a step up transformer between the VPI (I am using a dynavector Diamond MkIII cartriage). This improves the sound dramatically. I am using the Ortophon Vergo as the step up device.
I too have had this combination. Although the PH5 is listed as having the same amound of gain as the PH7, the PH5 does not work well with very low output cartriages. What I did to over come this problem was to install a step up transformer between the VPI (I am using a dynavector Diamond MkIII cartriage). This improves the sound dramatically. I am using the Ortophon Vergo as the step up device.