User Guide
34
REAR PANEL
Grandmother’s rear panel is populated by jacks and connectors that relate to the instrument as a
whole. Here is where you will nd audio and MIDI connections, additional CV I/O, a FINE TUNE knob,
the connection for the AC adapter with stress relief hook, and a Kensington security slot.
FINE TUNE
This knob controls the ne tuning of Oscillators 1 & 2, and is the default tuning
knob for Oscillator 1.
AUDIO
This group of jacks is dedicated to inputting and
outputting audio signals.
MAIN OUT / HEADPHONE OUT
This 1/4” TRS output is suitable for both headphone monitoring and
connection to an amplier, PA system, recording equipment, etc.
WARNING: Do not use a TRS (balanced) cable for line output applications as
this will cause phase cancellation and a very weak signal. Since the audio output
is in mono, it’s best to just use a standard 1/4” TS (instrument/guitar) cable.
INSTRUMENT IN
This 1/4” input allows an external sound source to be processed by
Grandmother’s analog circuits. There is no gain control for this input, so its
preamp has been designed to bring low level signals (like that of a guitar) up
to 10 Volts (peak-to-peak) in the Mixer. When connected to sources like a cell
phone, drum machine, or other synthesizers, this input can easily be pushed
into hard, musical clipping.
TIP: Even a high-output guitar signal can clip the mixer in some cases, which
may or may not be desirable. Be sure to use the volume knob on your external sound source to dial in
the sound you are looking for.
EURORACK OUT
This 3.5mm output duplicates the MAIN OUT signal, but at typical Eurorack
audio levels (-5 to +5 Volts).
NOTE: The output level of the EURORACK OUT jack is not controlled by the
VOLUME knob in the Output module