• Registered: 2020-06-15
  • Posts: 2

Topic: Babyface Pro FS - puzzling behavior with DI and line input signals

Hi,

Made a move recently from Focusrite Scarlett 2i2 gen 1 to RME BF PRO FS. Enjoying a significant upgrade across the board, except for a single issue with tracking bass guitar for parallel processing inside DAW.

My setup is simplistic: passive bass into Darkglass B7K preamp, which outputs 2 signals: processed output into BF input 3 (line), unprocessed DI output into BF input 1 (mic). Using mono unbalanced cables for everything.

When monitoring each signal isolated (not picking the other signal from B7K, cable is unplugged), everything seems to be fine - I'm getting audio in BF as expected. However, as soon as I have both signals going out of the pedal, BF gets lower volume and quality signals on both inputs. It appears as if the mic input 1 signal affects line input 3 signal inside BF itself.

The same setup worked fine with Focusrite Scarlett - B7K processed output into line in, DI output into mic/instr in, all good, latency aside smile

What am I doing wrong?

  • Registered: 2020-06-15
  • Posts: 2

Re: Babyface Pro FS - puzzling behavior with DI and line input signals

I guess I figured it out myself - surprisingly after revising the Focusrite manual.

Turns out I wasn't using its mic input for the DI signal, I was using its "instrument input" (I guess mic amp wasn't used, and the input impedance was definitely different, more suitable for instrument level signals).

And looks like the right way to get my parallel bass processing done is to route preamp into BF input 1 or 2 (have it in line mode, with pad active to avoid clipping) and preamp's DI signal into BF input 3 or 4 (which is hi-Z), and crank the gain there.

This seemed unintuitive to me initially, because I was keeping the gain down on "mic" input (having line level signal there) and low instrument level on a "line" input, but due to all the digital magic going on inside BF, it does work.

I hope my experience documented here will be helpful to others.