Plugins 2026-06-22
You need to be logged in to access this page
Oberheim OBX Tuning Cheat Sheet
(Eight x) Voice Board trimmer positions
Roland Juno-60 – Tape dumping factory patches to
I recently serviced a Roland Juno-60 that was unusually difficult when it came to the final step – uploading the Roland factory patches. What I had What I did I had almost full volume on the audio interface. If your volume is too low, you will not know until you have played the entire file without […]
JP-8000 Firmware Update to 1.05 – revised instructions
Instructions for Intel MacOS, using UpdSMF from Roland (link appears later). Roland’s last firmware for the JP-8000 is 1.05, and dates back to 1997. However, the firmware upload instructions in the accompanying readme file, are misleading if you are on a Mac. On a Mac you can’t load / play the SMF .MID files in […]
C program to calculate Swedish VAT for up to 20 items
You need to be logged in to access this page
How to Save a Patch on Jupiter-4 with IO midi mod
I did not understand it from the IO user manual: Covariant Instrument, Roland Jupiter-4 MIDI Make a patch in MANUAL mode. To save it: * It’s probably OK to press MANUAL once but it seemed a bit unreliable (To change bank, press one of the PRESET buttons)
Arduino – Create UF2 Boot File for Adafruit Feather M4
On MacOS. For Adafruit Feather M4 Express or any other SAMD51 (M4) or SAMD21 (M0) board that has Adafruit UF2 Bootloader installed. Noob level! Fast-Track Here’s the fast-track reminder for an M4, if you already have everything installed: Background There are some instructions on how to do this. Adafruit, for example, has this page UF2 […]
Notes: Arduino UDP (MIDI + text strings) over Ethernet
You need to be logged in to access this page
Protected: Solina String Ensemble / Kenton MIDI kit
There is no excerpt because this is a protected post.
Korg Mono/Poly Oscillator Tuning
Background Tuning instructions in the service manual are actually just fine. These are marginally easier to follow. What you need Preparations Step by Step Step 1 – Key Assigner (KLM-256) CV Connect the positive lead of your DVM (using a hook clip) to the right side of R8. Connect the DVM ground to GND at […]
Teisco Synthesizer 110F Oscillator Tuning, Using a Tuner & DVM
Background There are no tuning instructions in the service manual. The trimmers have unusual names, so it’s not obvious what do when opening it up. Here you go: What you need Preparations Step by Step Step 1 – Keyboard CV Connect the positive lead of your DVM (using a hook clip) somewhere on the grey […]
Multimoog Simplified Oscillator Tuning
When using a hardware tuner, you can ditch the unintuitive tuning instructions in the service manual. In my case that is a Peterson Strobostomp, but any tuner you trust can be used. Software, Apps, computers: Sometimes software tuners have trouble displaying very low, as well as high, frequencies. Often they are more sensitive to overtones, […]
Prophet-5 Rev 2 (Sequential Circuits, ca 1977) Tuning
The two tuning procedures (Production and Simplified methods) provided by Sequential Circuits in the Rev 2 service manual are complex, easily misinterpreted, and abstract – if you don’t have an intuitive sense of what you are doing, it’s hard to tell when you are not doing something right. It’s easy to miss a step or […]
Teisco SX-400 Basic Oscillator Tuning, Using Tuner and Oscilloscope
Background When tuning the Teisco SX-400, it’s hard to know what voice you’re currently hearing. Also you need to know which trimmer to use for upper end of the keyboard, and which to use for lower end. There are no tuning instructions in the Service Manual (which by the way is not much more than […]
Korg PolySix Tuning – The Long Story
The tuning of a Korg PolySix is mostly a tedious process. Let’s go in-depth to make it even worse. The tuning process described here is normally not necessary, but if you have replaced some components on the Voice PCB this might be your last resort. Sources of information The PolySix Service Manual. There is some […]
Arduino FastLED Library – a visual reference for the predefined colors
You need to be logged in to access this page
Ursa Major Space Station SST-282, 82S123 replacement
How to make a replacement for the 82S123 ROM chip (ADS-1 board – U19) in Ursa Major Space Station SST-282, using an 22v10 Programmable Logic chip and a cheap EPROM programmer. I used Atmel ATF22v10CQZ-20PU and the common TL866iiPlus. This is not a step-by-step guide, you are expected to know how to use an EPROM […]
The differences between Roland Juno-106 and MKS-7
This page compares the Roland MKS-7 to the Roland Juno-106. To understand it, you need to know the Juno-106. Some people say the MKS-7 is the rack version of Juno-106. But it’s more… and less. The Roland MKS-7 was allegedly intended for MIDI-file playback and karaoke, thus being a consumer market product. The voicing hardware […]
Arp Sequencer 1621 / 1601 Button Debounce
While servicing an Arp Sequencer 1621, I noticed that the three button switches were in a bad shape. One button press would produce anything from one to six signal changes. These switches can’t be sourced nowadays. The switches are glued together from factory so they can’t be opened. One possible fix would be to fit […]
Korg Lambda ES-50 Tuning Instructions
Disclaimer: There may be a better way to tune the Korg Lambda. My method is a bit “hit and miss”. Still it took less than five minutes to accomplish. Background The Lambda is not a VCO->Filter->VCA synthesizer, it’s constructed lika an organ / string machine. The tuning procedure is different and often simpler on an […]