[ORDER] Martin Devices - Soft Key

Soft Key

Pleased to finally announce orders for my Soft Key module! The soft key is a high gain voltage processor and precision clipper. The variable gain and clipping stage allows the module to act like a normal processor at low gain and at high gain the module will hard clip your input signal precisely between 0-1V.

The threshold control allows the input signal to be DC offset, controlling at what point the signal clips. The CV input allows an external signal to act as the threshold, and can be attenuverted with the CV control.

The gain control gives a range of x0 to x50, effectively attenuation up to hard clipping, but the trimpot on the board can be adjusted to increase the maximum gain to taste, up to x100.

The PCB is a four layer board designed to impart minimal noise when using high gain settings, but just as with any high gain circuit, noise on your signal will be amplified just the same as your signal!

This module is useful for signal processing, contrast control, shape generation and pairing with a crossfader to create a keyer.

  • 45mA +12V
  • 40mA -12V
  • 4HP wide
  • 52mm deep

BOM - https://github.com/martindevices/Martin-Devices/blob/main/Soft%20Key%20/BOM_Soft%20Key_2023-07-29.csv


PCB and Front Panel set: £20 / $26 + delivery from the UK
Built Module: £120 / $155 + delivery from the UK
DIY Kit: £110 / £140 + delivery from the UK

Payment via Paypal or BACS, any paypal fees covered by buyer


Either comment below or DM me for your order. Happy to do a run of black panels too if purple isn’t your thang

P.S. I just wanted to say a huge thank you to everyone who has provided advice and shared knowledge during the development, I’ve learnt a huge amount and I’m so excited to finally release a module!


Wow! Amazing :slight_smile:
Are you planning to offer full diy kits as well?

Hadn’t thought about it but if people are keen for a kit I can do one! £110 / $140 + Postage


Well done for getting this sorted. I’ll have a built one. This will be such a handy function in a small live case.


Hi, I would love a pcb/panel sent sent to the uk please

Cheers Analogmonster, PM’d you!

Ohhh, more DIY options!

Do you intend to release more modules?
And will you keep stock going forward, or will it be a run-by-run basis?

Since shipping (to Australia) is usually worth more than the PCB & Panel itself, I’d hold off and combine purchasing if that was an option for the future…

Hi Rik

Yep, I intend to hold some stock of boards where I can.

In the pipeline are a 2U video buffered mult, an individual outputs version of the Sandin Function Generator, A triggerable dual monostable and a vactrol sequencer style thing. Couldn’t tell you how long these will take though.

Also hoping to get some stocked with Thonk soon so you could always combine them with the other wonderful DIY offerings available.


Heck yeah, awesome work m8!

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@phosphenes - I’d probably just want pcb/panel set(s) and be happy to buy that from thonk if/when they get them in… unless you offer them here first (I’m in the UK so cheap postage)

would it be possible to see a BOM linked here though - it’s highly likely that I’d only need the ICs and some of the panel furniture… & if that’s the case I may want up to 3…

US based would love two DIY sets. super sweet.

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Hey, I’ve just added the BOM to my first post. Yep on offer here first! I’ve tried to stick to the ‘common’ video DIY values where possible, 1k, 499R, 4K99 etc so hopefully shouldn’t be any suprises on there.

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…hmmm - wanted to watch some of your examples, but instagram insists that i log in before showing anything…

…do you have videos somewhere else (Youtube? - Vimeo?) perhaps?…

4x panel+pcb to Spain please. :slight_smile:
In case you are planning to do black panels, I can wait for them and would prefer.

I’ll be uploading some demos, I’ve started a new job recently so I’ve been a bit busy but will get vids up soon!


I was just looking at this again and noticed the test points on the PCB. Nice touch!

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Thanks! Mostly for my benefit during development but I left them on for ease of debugging


Black panels available for the Soft Key, perfect for your Wayne Enterprises cases!


Black panels look great.Could you post some demos of the keyer? Think I might snag a pair.

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Thanks! Sorry I had some issues with my capture setup when I first released this, there’s a handful of patches with it in on my Instagram @Martindevices, I’ll try to record some simpler demonstrations of it in the next week.