Boss DR-110 temporarily repaired

Even doctors may need help sometimes… A few months ago, I got my Boss DR-110 that I bought on eBay on which only the HAND CLAP worked. All other sounds were there, but at a very low volume. With the help from the 99musik forum the BALANCE potentiometer became the primary suspect.

A few weeks ago I ordered a new 20KΩ linear potentiometer even thought the dimensions weren’t right, just to verify that the pot actually was the problem.

When looking at the PCB it was quite obvious that someone had try to repair/replace the pot before. It was quite badly done, one of the trace leading to wiper connection on the pot was loose.  I desoldered it and soldered a three lead cable that I inserted through the hole where the pot is supposed to be. I had to scrape the trace where the wiper had been and solder directly to it.

At first I forgot two bridge the earth that normally is though the body of the pot, but since I have no pot but three leads instead, I soldered a new lead to bridge the earth. Then the doctor was alive again! Now I only have to find a fitting potentiometer…

Another Behringer exception – BCR2000

One of the few Behringer products worth getting is the Behringer ADA-8000. The other one is the BCR-2000 which is a midi controller with 32 assignable rotary encoders that even do SysEx. Today I bought a used one with unknown USB functionality for 400 kr ($60). This will be perfect for the Roland JX-synths whose weakness is the lack of encoders. And the Kawai K3 and Waldorf Microwave as well…

Picture from the ad.
Picture from the ad.

Korg nanoKONTROL bought

Since my M-Audio Axiom Pro 49 just died, and I’m in the middle of an Arduino project, I desperately needed a new midi controller with lot’s of encoders. So i bought a Korg nanoKONTROL 2. Very nice, cheap and usable little thing. One thing that I actually missed to check before buying it was the fact that the “sets” from the nanoKONTROL 1 is gone in the nanoKONTROL 2. The only way to solve this is to use the nano kontrol software and save the settings. That’s very tedious though, and won’t be practical in reality. So my word of advice is to try and get a nanoKONTROL 1 instead.

M-Audio Axiom Pro 49 dead

Tonight my M-Audio Axiom master keyboard died, or at least acted weird. It seems like it had died “blue screen of death”, Google it. I contacted M-Audio for a new main board, but they don’t have them.

Thank you for your interest in M-Audio.

As you may know, M-Audio has recently become part of the InMusic family. We are thrilled to be manufacturing, distributing, and servicing new products under the M-Audio name and expanding the range of products we are able to offer throughout the US and the world. However, as this legacy product (Axiom 49 1st Generation) was not manufactured and/or distributed under the new ownership, these pieces and their parts will not be available from M-Audio.

So I guess I’ll have to scrap it. I don’t have any interest in M-Audio anymore. Never will.

Testing USB Midi on Teensy 2.0++

A week ago I purchased the official Arduino Starter Kit (ASK). I don’t know very much about electronics and felt that I should. Having a lot of vintage stuff will sooner or later require that!

I’m planning to build a custom Midi interface and realized that the ASK was very good for learning, but it didn’t have all the parts / functionality needed for both midi in and out. Fixing midi out is very simple, it only requires a resistor and a midi cable. Everything except the midi cable is in the ASK. There are a lot of examples on how to play simple midi notes. More about that some other time.

Since midi in is a must I purchased a Teensy 2.0++ board which is a variant of the Arduino. It uses the same development tools as the Arduino with some added plugins. The reason for choosing a Teensy for a project like this is because that it has USB HID functionality. This means that you can tell the Teensy what the device you connect it to should interpret the Teensy as. You can set the Teensy to be discovered as a midi device, and that’s exactly what I need. The special USB Midi library is called usbMIDI and there’s no good getting started code for it. Therefore I decided to share my first test with the Teensy using the usbMIDI library.

View video on YouTube (opens external site in new window)

Hooking up the components

First, the diagram. As you can see it’s very simple, digital out 4 (you can choose whatever digital out you want) is connected to a LED with a 220 Ω resistor in between.

The software that I made the image with didn't have a Teensy board so I took an Arduino board instead. You need a Teensy for USB HID to work.
The software that I made the image with didn’t have a Teensy board so I took an Arduino board instead. You need a Teensy for USB HID to work.

A photo of the build:

This is what the circuit look like. I haven't soldered any pins on the Teensy yet, this is a temporary solution!
This is what the circuit looks like. I haven’t soldered any pins on the Teensy yet, this is a temporary solution!

The code

void setup(){
pinMode(4, OUTPUT); //Use digital out 4 for the LED
usbMIDI.setHandleNoteOn(OnNoteOn); //Specify which function to handle NoteOn events
usbMIDI.setHandleNoteOff(OnNoteOff); //Specify which function to handle NoteOff events

void loop(){; //Start listen for MIDI events from USB

void OnNoteOn(byte channel, byte note, byte velocity){ //This is the function that handles NoteOn events
if(note == 60){ //If the note was C4 = 60
digitalWrite(4, HIGH); //5V ON

void OnNoteOff(byte channel, byte note, byte velocity){ //This is the function that handles NoteOff events
digitalWrite(4, LOW); //5V OFF, doesn't matter what note you release