Showing posts with label HOX808. Show all posts
Showing posts with label HOX808. Show all posts

Tuesday, June 11, 2024

Orpho VLPF - Eurorack Vactrol Low-Pass-Filter

video upload by HOX808

"The Orpho VLPF is an active low-pass filter module for modular synthesizers in the Eurorack format. It is a fully resonant low-pass filter that uses vactrols as controlling elements for the filter frequency and resonance. The two potentiometers for frequency and resonance set the desired filtering. The more they are opened, the more light falls on the two LDRs. By changing the control voltage, frequency, volume, and resonance change simultaneously. The potentiometers allow the adjustment of the light impact to achieve fine gradations. The two LEDs are exposed to provide a visual representation.

A fully resonant filter shows significant amplification at its resonance frequency, leading to a sharp peak in the frequency response. The quality factor (Q-factor) determines the sharpness of this resonance: a high Q-factor implies a sharp resonance, while a low Q-factor results in a more damped resonance. Fully resonant filters can also tend to oscillate in the absence of an input signal when set to maximum amplification, a phenomenon known as self-oscillation.


A vactrol is a combination of a light-dependent resistor (LDR) and a light-emitting diode (LED) housed in a common, light-tight enclosure. Increasing the LED brightness decreases the resistance of the LDR. This can be used for various circuits that rely on variable resistances. These components are known for their "soft" sound, as they are linear elements that do not cause distortion.

Module Overview:

- VLPF with vactrol control
- Fully resonant filter
- Self-oscillation possible
- High-quality potentiometers
- CV input
- Two LEDs behind the front panel for visual representation
- Amazing organic sound, ideal for drum snappy sounds and bongo sounds

Enclosure and Power Consumption:

The VLPF is 3U high, 8HP wide, and 18mm deep. Power consumption: +12V, -12V | 40mA."

Saturday, July 10, 2021

orpho voodoo drum machine | Eurorack modular tube drum machine with dynamic 8 step sequencers...

video upload by HOX808

'Die Voodoo Drum Machine befindet sich in der Forschungsphase mit 4 Modulen aus der Voodoo Drum Serie und 4 dynamischen Trigger-Sequenzern die in einem diskreten Mixer zusammengemischt werden. Möglicherweise wird es eine limitierte Auflage geben..."

Friday, May 22, 2020

Orpho Vollrausch ( BLACK) | Vacuum Tube VCO / Noise Generator Eurorack Module + VC LFO, DIODE FILTER

Published on May 22, 2020 HOX808

The silver panel made its appearance in November of last year.

"The new variant of the Vollrausch. Now he comes in a casual black robe. In the first part of the video you can hear the pure sound of the module. Later an LFO orgy flew.

The LFO will also be available soon. The show must go on..."

Sunday, February 09, 2020

ORPHO KICK DRUM 2 | Eurorack Module | Analog Modular Bass Drum

Published on Feb 9, 2020 HOX808

"In addition to the new design, the second version of the kick drum now also has a CV input."

"Depending on your preference, various kick sounds can be generated. The sound generation of the Orpho Kick Drum is thanks to a sophisticated T-drum oscillator, which is divided into two areas. Each area is assigned to a controller. The sound character can be influenced in many ways by the two scope controls, even self-oscillation is possible!"

Thursday, March 07, 2019

Replica of the Moog 901B oscillator

Published on Mar 7, 2019 HOX808

"Moog 901 B Oscillator | Original replica from the year 1969. Except for the D2 diode, all components are easy to obtain. The N 4148 diode is ideal as a replacement. For operation without a 901A controller, the resistors R31, R32 must be supplied with current + 11.5V. The node 'B' must also be connected to the power supply. For the CV control the node 'A' is responsible."

Monday, May 22, 2017


Published on May 22, 2017 HOX808

"The Orpho Flash Trigger, allows a flash-like triggering of 16 steps for 8 tracks each. Excellent for intuitive use.
A step is set or deleted by pressing a key. If the Enter key is pressed, all subsequent steps are set. The Orpho Flash trigger is in the test phase and has the status of a prototype."

Monday, August 01, 2016

Wav Trigger Eurorack Module with 16 sockets , triggered by Game System , Modular Sampler

Published on Aug 1, 2016 HOX808

"The famous Korg Minipops 7 sounds loaded onto the SD card. controlled by various sequencers."

Info on Wav Trigger board used in this module by HOX808, via sparkfun:

"Description: The WAV Trigger is a unique high-fidelity polyphonic audio player with surprising capabilities. Supporting up to 2048 uncompressed 16-bit, 44.1kHz wav files – the same quality as an audio CD – the WAV Trigger can play and mix up to 14 stereo tracks simultaneously and independently, with very low latency. Tracks can be controlled via 16 programmable trigger inputs, or by using a native serial control protocol or even MIDI.

Trigger inputs can be connected directly to switches and buttons, or to digital outputs from sensors or another microcontroller. Alternate functions can be specified using a free cross-platform GUI application, and allow triggers to play sequential or random tracks, pause and resume groups of tracks and even control volume. An Arduino library allows for complex serial control like real-time mixing, starting multiple tracks in sample-sync and smooth cross-fading between tracks.

On-board sample rate conversion allows for smoothly changing playback speed/pitch from 0.5x to 2x. in real-time.

MIDI allows you to use the WAV Trigger as a polyphonic sampling synthesizer to play your own sounds from any MIDI keyboard controller. MIDI Channels and Note numbers are mapped to track numbers, and MIDI Controllers adjust volume as well as attack and release times. MIDI Program Change is supported to switch between up to 16 banks of 128 sounds. The WAV Trigger audio engine even implements, pitch bending, voice stealing (oldest playing voices are used for new MIDI Notes when all 14 voices are being used), note attack (fade-in), note release (fade-out) and latency averages 8 ms.

The WAV Trigger supports both SDSC (up to 2GB) and SDHC (up to 32GB) type microSD cards.

Check the link in the documents below to keep up with the latest Firmware updates!

Note: This product is a collaboration with Robertsonics. A portion of each sales goes back to them for product support and continued development."

Thursday, June 23, 2016

Speak and Read EURORACK MODULE with Circuit Bent Modification I CV IN, Trigger IN for Modular

Published on Jun 23, 2016 HOX808

"GAME SYSTEM plays Speak and Read EURORACK MODULE with Circuit Bent Modification I CV IN, 2x Trigger IN for modular connection. All drum sounds coming from the Orpho Modular Drum."

Saturday, February 27, 2016


Published on Feb 27, 2016 HOX808

"Orpho Modular Drum is a drum set for the Eurorack. It consists of 8 different drum voices, bass drum, snare, Hi-Hat, 3xcConga Low, Mi, Hi and 2 x RIM shot.
The circuits are similar to the drum machines of bygone days.
Each module is manufactured by myself, without the use of SMD components.
100% analog, in every respects!
The modules will be available soon for sale."

Follow-up to Moog Mother 32 ACID JAM with TB 303 and Modular ANALOG DRUMs.

Tuesday, February 16, 2016

Moog Mother 32 ACID JAM with TB 303 and Modular ANALOG DRUMs

Published on Feb 16, 2016 HOX808

"The drum voices come from ORPHO Modular Drum. The kick thunders from the x base 09."

I'm guessing the ORPHO is new from HOX808. If you know feel free to comment. I left a comment on YouTube for HOX808 and will report back if I hear back.

Update: some info via HOX808:

"The Orpho Modular Drum is a drum set for the Eurorack. It consists of 8 different drum voices, Bass Drum, Snare, Hi-Hat, 3xConga (Low, Mi, Hi) and 2 x RIM shot.

The circuits aresimilar to the drum machines of bygone days. Each module is manufactured by myself, without the use of SMD components. 100% analog, in every respects! The modules will be available soon for sale.

More information coming soon..."

Tuesday, September 01, 2015


Published on Aug 31, 2015 HOX808

"Analogue bass drum voice with a wide adjustment range of the two-drum oscillators. Dynamic trigger input with depth control. 6HP, Eurorack Module. Created by HOX808, Berlin Germany."

I created a new HOX808 label for these moving forward. A search on HOX808 on the top right of the site will bring up previous posts.

Switched On Make Synthesizer Evolution Vintage Synthesizers Creating Sound Fundlementals of Synthesizer Programming Kraftwerk

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