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Eoo3: Programmable Looper/Switcher/Midi Controller

Started by Marshall Arts, November 01, 2018, 01:54:30 PM

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brejna

This project is getting better and better.. [emoji106]

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Marshall Arts

#61
Update: The display arrived and was really easy to assemble and to get up and running. I am using an external 32k EEPROM for the Banks and Presets, and with the display, I am now able to store:

- 60 Banks with 7 Presets in each bank.
- Each preset can send up to 7 Midi Commands (PC/CC, each with individual Midi Channel). CC's on preset buttons don't toggle between values.
- Each Loop Button (top row) can also send 7 Midi Commands (PC/CC, each with individual Midi Channel). CCs on Loop Buttons can toggle between two values (e.g. 0 for "Block Off" and 127 for "Block On"). The two values can be set freely for each CC.
- Now the crazy bit: A Loop Button recalls a stored set of loop states (e.g. Loop 1-2 on, Loop 3-8 off). With each of the loops being able to send out a sequence of Midi Commands themselves, the activation of a preset will trigger its own Midi Commands but also the commands for each of the loops (e.g. send CCs for Loop 1-2 with a value 127 and CCs for Loop 3-8 with value 0). IF A PRESET BUTTON TRIGGERS THESE SUBSEQUENT MIDI-EVENTS from the loopstates or not can be defined for each preset.





gordo

I don't even know what half of that means and I'm STILL excited about it  :D

This thing is getting hardcore.
Gordy Power
How loud is too loud?  What?

Marshall Arts

Quote from: gordo on January 06, 2019, 06:17:16 AM
I don't even know what half of that means and I'm STILL excited about it  :D

This thing is getting hardcore.
Great, Gordo, thanks.

In an only-midi-world, that means, that you can assemble complex presets for multi-midi -device rigs and activate them with one button press. In addition, you can still toggle individual blocks within a preset on and off.

But the world is not plain midi : You can combine the above with looped analog pedals AND Amp channel switching.

I am eager to get this done over the next months. .. Total material costs would be around 120 EUR, incl Buttons, Enclosure, Jack's, Components... And a lot of DIY Time (offboard jacks, LEDs and switches, Display Cutout,... ).

Still, very, very competitive to market solutions. I would love to create a feature matrix of midi loopers for comparison. I guess that this thing falls short in loop order  (it's fixed) and maybe editing convenience.

cooder

That's really so far out there! Amazeballs!
BigNoise Amplification

Aristatertotle

This is beyond intense.

So with the press of a button you could switch analog pedals, an amp channel, midi presets on a couple of pedals, and a backing track on ableton or something of the like.  :o

I think the next logical evolution is to have a switch for "keyboard" mode where you can use the foot switches to control a virtual instrument like drums or a bass synth.  ;D

Marshall Arts



Quote from: Aristatertotle on January 06, 2019, 03:02:56 PM
This is beyond intense.

So with the press of a button you could switch analog pedals, an amp channel, midi presets on a couple of pedals, and a backing track on ableton or something of the like.  :o

Yes. Actually, you could have ableton trigger the Looper as well during the playback (it has midi in for program changes as well) :-)

I skipped midi notes for now, to not loose focus.

gordo

Room is starting to spin...I'm feeling a little diz.....
Gordy Power
How loud is too loud?  What?

Marshall Arts

Did some Audio testing today, unfortunately, the Display produces Major interference through gnd and/or vcc.... Damn. Anybody experience with Displays? This one uses a HT16K33 chip for Multiplexing. I dont want to add a filter circuit, if I dont have to, so a Display that just multiplexes when it has to Show a new number would be better (as Audio is muted during switching anyways...


Marshall Arts

#69
...when your imagination exceeds your breadboard size  ;D



Needed to put it all together to be able to measure power consumptions. With all eight loops on, it will be somewhere between 400 to 450 mA @ 9 Volts. Kind of what the commercial pedals (Boss etc.) use as well, so it's not too bad....

Progress: I ordered another display, that is not driven by an HT16K33 but a TM1637:

https://www.az-delivery.de/products/4-digit-display?ls=de&cache=false

Bad news is, that I need another free pin on the Arduino, as it is not adressed via i2c, so I will likely have to reduce the number of preset buttons from 7 to 6... fair enough and no big deal with 60 banks available.

Concerning the enclosure (Blocan Cable Channel)



As it seems to be hard to find in the US, I found a good google search term: Aluminum Extrusion Enclosure



Did not check on prices for custom length though. Any other suggestions welcome (maybe the US guys could have a look in their local hardware stores for alternatives).

Required size: 8 cm (3,15") deep, 4 cm (1,57") high, 60 cm (23,6") long. Please post suggestions here.

jjjimi84

I can offer no help but this thing looks absolutely amazing. I love watching the progress

Marshall Arts

Too bad... The new display produces interference as well, so both drivers (HT16K33 and TM1637) fail so far due to multiplexing noise. I will try to fix it with a separate power supply and filter caps, but search for better solutions goes on, support welcome. Does anybody know of a DIY-Pedal with 7 segment displays (3-4 digits), where I could get some inspiration?

brejna

Quote from: Marshall Arts on January 22, 2019, 11:45:29 PM
Too bad... The new display produces interference as well, so both drivers (HT16K33 and TM1637) fail so far due to multiplexing noise. I will try to fix it with a separate power supply and filter caps, but search for better solutions goes on, support welcome. Does anybody know of a DIY-Pedal with 7 segment displays (3-4 digits), where I could get some inspiration?
I think Thomas from thcustom effects had developed switcher with 2 or 3 digits..

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brejna


Marshall Arts

Thanks. What a crazy project. Thomas is my hero :-). It uses a separate shift register / decoder, stuff I currently cannot deal with (not enough time).
I will try to separate the power supply for the LED display and see how that helps.