I had a look at a couple of continuous gain VP26’s the other day, and thought I’d share these frequency and phase response plots. This is gain minimum with pad, gain minimum, gain with pad matched to gain minimum without pad, gain maximum with pad.
You can see the changing feedback in the bottom end, but it’s pretty minor. Neither does the pad or the change in feedback make much difference in the top end. Really pretty well behaved compared to many transformer coupled preamps.
full size pic HERE
Related, if you want to match minimum gain without a pad to gain with a pad, the knob is gonna move from 7 o’clock to roughly 2:55 to make up the 20.25 dB loss of the pad. I see that freak a lot of people out, they become afraid to use the pad because the knob setting seems ‘wrong’ to them. The plots show there’s little measurable change from using the pad, with the majority of change in sound coming from the resistive isolation of reactive elements in the mic and preamp transformers.
November 26, 2018, 09:42:20 AM