Making a TeensyMIDIAudio board is not very difficult, but you should consider the following:
* You should've soldered something before. Preferably a small kit. Without some practice you will get problems with bad soldering points and such errors are always very difficult to find if you have not worked properly. Instructions on how to solder and which tools are necessary for it, you will surely find on the Internet.
* You need time! Someone with a lot of experience and practice can finish the whole kit in 2 hours. But if you don't take enough time, there is a high risk to fill something wrong or to create bad soldering spots.
* You need good tools. Good doesn't always mean expensive. But don't try to work with unsuitable tools - this leads to problems.
* You should've soldered something before, preferably a small kit. Without some practice you will get problems with bad soldering joints. Errors like this are always very difficult to find if you have not worked properly. Instructions on how to solder and which tools to use can surely be found on the Internet.
* You need time! Someone with a lot of experience and practice can finish the whole kit in 2 hours. But if you don't take enough time, there is a high risk to fill something wrong or to create bad soldering joints.
* You need good tools. Good doesn't always mean expensive. But don't try to work with unsuitable tools, because it may also lead to problems.
## Tools
* Soldering iron: It is best to use a temperature-controlled soldering iron or a station with a power of about 40 watts or less. Never use soldering tips that are too large or a soldering iron with a large capacity.
* Soldering iron: It is best to use a temperature-controlled soldering iron or a station with about 40 watts of power. Never use soldering tips that are too large or a soldering iron with a large capacity.
* Soldering tin
* (Small) Side cutter
* "Helping hand" or fastening material (which is heat resistant)
* "Helping hand" or heat resistant fastening material
* Stripping tool
* Hot air pistol for shrinking tube
* Hot air gun for shrinking tube
## Build
The printed circuit board has numerous optional components that only need to be mounted in certain cases. This guide shows you all possible options and indicates whether the step is optional or recommended. All steps without further hints are necessary.
The printed circuit board has numerous optional components that only need to be mounted in certain cases. This guide shows you all possible options and indicates whether steps are optional or recommended. All steps without further hints are necessary.
It is also possible to equip the board with a PT8211 I2S audio chip. This option is not shown here. If you want to use this option, you can use the schematic as help or ask directly via email or in the forum.
It is also possible to equip the board with a PT8211 I2S audio chip instead of the Teensy Audio Shield. This option is not shown here. If you want to use this option, please take a look at the schematic or ask directly via email or in the forum.
The build process is organized into several steps (each step on one page, often with a photo). It is a good practise to make a break after each step. For steps were you have to solder very much (like the IC sockets) you should make breaks in between.
The build process is organized into several steps. Each step is on one page with pictures showing the relevant changes. It is good practise to take a short break after each step. For steps in which you have to solder very much (like the IC sockets) you should take breaks in between.
Be carefull when soldering on the Teensy audio board! You should take care not to stay too long on one soldering point and allow breaks to cool down the soldering points so that the chip on the board is not damaged.
Be careful when soldering on the Teensy audio board! You should take care not to stay too long on one soldering point. Again, take breaks to let the soldering joints cool, so that the chip on the board will not be damaged.
I you are unsure or the manual is not precise enough (or perhaps wrong?), please asl by email or forum before doing something wrong!
If you are unsure or the manual is not precise enough or misleading, please ask by email or forum before doing something wrong!
__Note: The photos show a mounted SMD component (type PT8211). This is not necessary and is not pre-assembled.__
@ -88,7 +88,7 @@ __Note: The photos show a mounted SMD component (type PT8211). This is not neces
* 1 Teensy-3.6 (or Teensy-3.5 with some limitations, __Teensy-4.x will not work with this board!__)
* 1 SD card 2-32GB
* 1 Teensy audio adapter board (Rev. C, __the Rev. D board for Teensy-4.x will not work!__)
* 1 [Teensy Audio Shield](https://www.pjrc.com/store/teensy3_audio.html) (SGTL5000, Rev. C, __the Rev. D board for Teensy-4.x will not work!__)
* 1 USB power supply
### Assembling the kit
@ -149,7 +149,7 @@ You need:
#### IC sockets
__Note the direction in of the IC sockets: If the board is like in the picture below, the notches of all IC-sockets must point to the left.__
__Note the mounting direction in the IC sockets: If the board is aligned like in the picture below, the notches of all IC-sockets must point to the left.__
You need:
@ -164,7 +164,7 @@ You need:
#### Double-row pin headers
You have to cut the needed number of pins from the long double-row-headers by yourself. Only JP4 is needed, the rest are optional signals and ground pins if you want to extend the hardware by yourself. For more information take a look at the circuit diagram.
You have to cut the needed number of pins from the long double-row-headers on your own. Only JP4 is needed, the rest are optional signals and ground pins if you want to extend the hardware by yourself. For more information take a look at the circuit diagram.
You need:
@ -181,7 +181,7 @@ You need:
#### Single-row pin headers
You have to cut the needed number of pins from the long single-row-headers by yourself. Only JP1/JP2/JP3/J7/J6/J17 are needed, but it is recommended to solder the remaining headers as well. For more information take a look at the circuit diagram.
You have to cut the needed number of pins from the long single-row-headers on your own. Only JP1/JP2/JP3/J7/J6/J17 are needed, but it is recommended to solder the remaining headers as well. For more information take a look at the circuit diagram.
You need:
@ -218,15 +218,15 @@ You need:
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#### Solder the audio card
#### Solder the Teensy Audio Shield
You have to cut the needed number of pins from the long single- and the double-row-headers by yourself. The 2 * 2 pins are optional and only needed if you want to use the option for audio-input. The 3-pin-single-row header on the right picture (for GND/VOL/3.3V) is not needed.
__Be careful bot to overheat the onboard chip when soldering the headers. Make a small break after soldering every pin to let it cool down.__
__Be careful not to overheat the onboard chip when soldering the headers. Take a small break after soldering every pin to let it cool down.__
You need:
* Teensy audio card (not included in the kit)
* Teensy Audio Shield (not included in the kit)
* 1 * 3 pin rows
* 2 * 14 pin single row
* 2 * 2 pin rows (__OPTIONAL__)
@ -240,7 +240,7 @@ You need:
You have to cut the needed number of pins from the long single-row-headers by yourself.
__Be careful bot to overheat the onboard chips when soldering the header. Make a small break after soldering every pin to let it cool down.__
__Be careful not to overheat the onboard chips when soldering the header. Take a small break after soldering every pin to let it cool down.__
You need:
@ -253,7 +253,7 @@ You need:
#### Solder the encoders
The kit contains 10 cables with open ends. These open ends must be stripped, tinned and soldered 5 per encoder. To be on the safe side, heat shrinkable tubing should be put over the soldering points. For this you have to cut 10 pieces out of the long shrink tube by yourself.
The kit contains 10 wires with open ends. These open ends must be stripped, tinned and soldered. You need 5 wires per encoder. To be on the safe side, heat shrinkable tubing should be put over the soldering joints. For this you have to cut 10 pieces out of the long shrink tube.
You need:
@ -268,7 +268,7 @@ You need:
#### Insert the ICs
__Note the direction in which the two ICs must be inserted: If the board is like in the picture below, the notches of both ICs must point to the left.__
__Note the direction in which the two ICs must be inserted: If the main PCB is aligned like in the picture below, the notches of both ICs must point to the left.__
You need:
@ -281,7 +281,7 @@ You need:
#### Insert the Teensy
__Note the direction in which the Teensy: If the board is like in the picture below, the SD card slot must point to the right.__ Also connect the USB adapter cable so that the thicker black of the female connector is located to the right (like in the picture below).
__Note the direction in which the Teensy must be inserted: If the main PCB is aligned like in the picture below, the SD card slot must point to the right.__ Also connect the USB adapter cable so that the thicker black end of the female connector is located to the right (like in the picture below).
You need:
@ -305,9 +305,9 @@ You need:
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#### Insert the audio card
#### Insert the Audio Shield
__Note the direction in which the audio card: If the board is like in the picture below, the SD card slot must point to the right.__
__Note the direction in which the Audio Shield must be inserted: If the main PCB is aligned like in the picture below, the SD card slot must point to the right.__
You need:
@ -317,9 +317,9 @@ You need:
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#### Connect audio card
#### Connect Audio Shield
Connect the audio ports of the audio card to the pin headers on the main PCB. You only need to connect the audio-out part, but it is recommended to also connect the audio-in connectors. For the wiring look at the wiring scheme below.
Connect the audio ports of the Audio Shield to the pin headers on the main PCB. You only need to connect the audio-out port, but it is recommended to also connect the audio-in port. For the wiring look at the wiring scheme below.
You need:
@ -333,7 +333,7 @@ You need:
#### Prepare and insert SD card
Format the SD card as FAT32 and copy the contents of the directory *addon* from the *MicroDexed* directory to the SD card. You can also install your own SYSEX files (or load them directly onto the MicroDexed later). It is important to keep the directory structure: for each bank there is a directory with the bank number as name.
Format the SD card as FAT32 and copy the contents of the directory *addon* from the *MicroDexed* directory to the SD card. You can also install your own SYSEX files (or load them directly onto the MicroDexed later). It is important to keep the directory structure: For each bank there is a directory with the bank number as name.
The SD card can be inserted into the Teensy or the audio card.
@ -359,7 +359,7 @@ You need:
#### Setting jumpers
The jumpers are needed to decide which kind of I2S sound chip you want to use and to enable the I2C pullup resistors. To enable them close JP4 and JP5. Than set JP3 to the down position (as seen in the picture below) and leave JP1 and JP2 open.
The jumpers are needed to decide which kind of I2S sound chip you want to use and to enable the I2C pullup resistors. To enable them close JP4 and JP5. Then set JP3 to the down position (as seen in the picture below) and leave JP1 and JP2 open.
You need:
@ -387,37 +387,39 @@ You need:
Now you are ready for the first test. But before, please check again the following:
* orientation of the ICs
* oruientation of the Teensy
* orientation of the audio card
* orientation of the Teensy
* orientation of the Audio Shield
* SD card is inserted
![](images/180.jpg)
Now you can try to power your kit. If everything works, the display should show a short text during the boot process. After that you are in the bank/voice selection.
Now you can try to power up your kit. If everything works, the display should show a short text during the boot process. After that you you should see the bank/voice selection.
##### Problem: Nothings visible on the LCD
##### Problem: Nothing is visible on the LCD
This can happen if the contrast of the LCD display is not set correctly. To adjust it you can (carefully) adjust the contrast with a small screwdriver on the blue pot on the back of the LCD display when it is switched on.
This can happen if the contrast of the LCD display is not set correctly. To adjust it you can (carefully) adjust the contrast with a small screwdriver using the blue potentiometer on the back of the LCD display while power is connected.
![](images/300.jpg)
##### Problem: The Screen hangs on the boot message
##### Problem: The screen hangs on the boot message
Has the SD card been recognized? You can only hear the sound if the SD card has been recognized correctly. If not, format it again as FAT32 and copy the data or try another SD card. If the SD card is not recognized, the system will stop.
This may be due to problems with the SD card? The synth will only work if the SD card works correctly. If the SD card is not recognized, the system will stop. Try to format it again as FAT32 and copy the preset data or try another SD card.
##### Problem: The encoder work upside down
##### Problem: The encoders are reversed
The lines on the encoder (on the three-pin side, the lines on the right and left) have been plugged into the motherboard in reverse order. Exchange them crosswise on the main board.
The lines on the encoder (on the three-pin side, the lines on the right and left) have been connected to the headers in reverse order. Exchange them crosswise on the main board.
##### Problem: The encoder buttons won't work
##### Problem: The encoder buttons don't work
Check if the two wires from the encoder (from the two pole side) are connected to the correct position on the main board.
Check if the two wires from the encoder (from the two pin side) are connected to the correct header on the main board.
It is also possible that the potentiometer knobs are mounted too close to the encoder. Loosen the screw in the potentiometer knob and push the knob a bit higher or remove it first and test again.
It is also possible that the potentiometer knobs are mounted too close to the encoder. Loosen the screw in the potentiometer knob and push the knob a bit further away from the case. You can also remove it first and try to push the buttons without the knobs.
##### Problem: There is no sound
First check your MIDI wiring. Are you getting signals? There should be a note or a box under the inverse 1 when you press a key. If not, no MIDI signals are detected and no sound is generated.
First check your MIDI wiring. Are you getting signals? The LCD should show a note symbol or a box symbol under the inverse 1 when you press a key. If not, no MIDI signals are detected and no sound is generated.
Did you reset the EEPROM? You may need to reset the EEPROM after each time you flashed the firmware.
Is the volume high enough? Turn the volume encoder (left) so that the display shows you a higher value (maximum 100).