Isobar Umbra: Stereo Feedback Accumulator

Getting feedback right can provide glorious lift to your music, with infinitely repeating sounds growing with intensity! Here we have a look at the Isobar Umbra - a Stereo Feedback Accumulator which really hits us in the feedback feels. The video is presented by Metamyther who talks about the unit before going into details. Here's what the product page says... 

Features:
- Discrete transistor core VCAs for input gain (L and R), VCA pair for return gain, and VCA pair for feedback amount.
- Switchable between stereo operation and serial mono operation, where the output of the left channel enters the input on the right channel, doubling up on feedback and processing, indicated by the color of the LEDs. Orange L and R channels = Stereo operation, Orange L channel, Blue R channel = Serial operation
- Asymmetric diode soft clipping distortion at output.
Level LEDs for input level and return level, to keep feedback, drive and gain under control.

Detailed Description:
Umbra is a dual channel feedback processor with three discrete transistor core VCA pairs. Route any eurorack-level effects, compressors or filters through its send/return paths to create feedback loops ranging from subtle textured echoes to howling walls of sound. The input level VCA is positioned before the feedback circuit, allowing time based sounds to fade naturally when the VCA is closed. A soft clipping stage after all feedback keeps levels controlled while adding nonlinearities and character. The left-right channel normalling allows for both mono-to-stereo or true stereo operation.

Uses:
- Adding a filter, filter bank, delay, reverb, waveshaper, or any other effect into the feedback loop.
- Heavy soft clipping distortion.
- No input feedback mixing.
- 3 stage VCA with distortion

Specs:
Height: 3U (128.5mm)
Width: 10hp (50.8mm)
Depth from panel: 34mm
+12v: 102mA
-12v: 44 mA
5v: 0mA

More on the unit can be found on their ETSY page

Video timestamps below..

00:00 - Intro

01:20 - Vhikk X Example

04:46 - Drum Example

06:49 - Saturation

07:35 - Multigrain

08:17 - Cursus Melody

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