Axoloti Powered Bass Effects System

[Gavin]

Part one of my project can now be shared with the community,
The official system is taking shape.

My Requirements..
- All has to fit into a case.
- Display is via a VGA monitor.
- Axoloti Module must be detachable for desk top use.
- Axoloti module must require a hardware structure that can be used in any patch.
- Axoloti Module must be controlable from a foot pedal system and must be able to make all required adjustments to the patch when active.

Features..
Input/Output seperated into Input - Send - Return - Output.
8 momentary switches for active control within patches.
2 bank momentary switches with states 00,01,11,10 for 4 banks of 8 switches. The 8 switches can also be doubled up with there adjacent switch for an additional 7 momentary switches if required. This gives a total of 60 momentary switches per patch if required.

The 2 bank switches also double as mode switches when held for period of time. This will changes the switches from momentary switches in the patch to adjustable parameters either Polar or Bipolar depending on the need. 6 of the switches provides an increment decrement option of +16, -16, +4, -4, +1, -1, the other 2 switches allows me to select the parameter to adjust between 1 and 32.

Still to do..
The footswitching unit is mostly complete, some of the switches were busted so need to order some new ones.
Need to finalize how the patches will be setup, so will require a template patch so all the controlling is the same, everythying is currently in smaller patch peices and needs to be brought together.
Need to finalize the display setup, how it will be displayed and change etc depending on adjustments and how description details will be shown and stored etc..

Some photo's, not the best..

In the case.

Axoloti Module.

Little VGA taste with a pixelated Axoloti..

Axoloti Module on the desktop.

I can post some more photo's of any other details if you like.. !

[Gavin]

I have made some changes, I decided to update the module to better reflect the interactive menu and prest management currently under developement.
This should be almost 100% in line with my desired outcome.

Details..
16 momentary switches (added additional 8)
4 momentary mode switches (added additional 2)
4 expression pedal inputs (added additional 2)
2 Foot Rotary Encoder inputs .NEW. (yet to build the foot unit)
Headphone output from Axo .NEW. Mono mode with switch between Send and Out.

Note.. The 20 momentary switches only use 5 digital Axo inputs with binary coding.

Still to come..
- add SD Card SPI to module to control data for interactive menu.
- Build foot switching unit with 20 momentary footswitches.
- Build 4 expression pedals into 1 unit.
- Build 2 foot controlled Rotary Encoders into 1 unit.

[kat]

Thanks for sharing your progress... I'd love to see gut shots sometime, and I'd also love to hear some sound clips. But maybe that's just being greedy! I am really curious to hear how you end up using this system and what it lets you do.

[Gavin]

Sound wise, its an open book, I still don't know how the patches are going to eventuate, the most important thing in the design was to ensure I don't get to a point where I have limited myself. What I actually imagine is I will start with very simple setups, and everything will grow from there over time.
The interesting thing I find, is most setups you get from other multi effect systems are somewhat simple, and this is why I like the Axo so much, it will let me learn about how the Synth side of things manipulates audio etc, and apply these to bass guitar effects.
Further updates to the above.. SD Card with data for interactive menu has been added, the software to manage the data is done, however working now on building the Arduino code to manage the menu and its data, this is a bit slow as I am currently working through some communication control between arduino and Axo so the parameter values display the correct data on the screen. I have also built a working model of the foot controlled rotary encoder, needs a bit of rebuilding, may only have one instead of two.

[Gavin]

@kat, some soldered connections came apart today, so when I opened it up, I decided to take some "gut" photo's if your interested....

Enter at your own risk, Its not pretty...

Axoloti, I have removed the Midi, stereo jacks in and out, host usb.

Arduino due. (i should have done the perf board the other way around..)

Both together with connections. You may notice a smaller rectangle peice of perf on the larger perf connected to the Axo, this is a diode matrix, that connects the 20 momentary switches to 5 axoloti GPIO's using the diodes to represent a binary value of the momentaries. This can also be connected to the Arduino due in the same way, so I have both options, currently connected to the Arduino to send the value to the Axo as midi through the uart.

Inside of the front panel. The only things not connected are the 2 stereo jacks in the middle.

Mounted Items. The removed midi section, extra perf board containing Arduino Due USB programmming port, Axo programming port, both link to extensions connecting to the micro usb inputs, Axo host USB to axo board where it was removed from, VGA output from Arduino due, 9 pin output din to connect up and comming footswitches to the Axo / Due, and an SD card module that you cannot see connected to the arduino due to store patch details and presets etc. all are with basic male / female pin sets to disconnect if needed.

everything is spread out ready to be re-assembled.

Everything assembled front pannel.

Everything assembled from the rear. Designed to make it easier to work on by just removing the base of it. Bit of a squeeze but it fits..

So there you go. Quite messy indeed and believe it, it actualy works, but I think I've designed it in a way where I can easily tidy it up bit by bit, without sending the work backwards.

The footswitches we be in line with the front panel 20 momentary switches except laid out 5 across and 4 down, with the first four columns left to right top to bottom 1 to 16, and the last column, the 5th column top to bottom 17 to 20. connected to an additional diode matrix then with only 5 wires going to either the Axo or Due, + 3.3V, GND, leaving 2 wires left of the nine, I may use for an LED or two. Thats all.

[kat]

Hi @Gavin,

Thanks for all the extra information and posting all your images. I was especially curious to see how you handled the Axoloti I/O ... and perhaps this will inspire me to feel braver about removing the built-in jacks so that I can set something up that is boxed durably... which is still a problem I am having. Also I am interested in how you are using the Axoloti and the Arduino together. I have some separate projects using a Teensy right now and haven't really thought much about how the Teensy and Axo might "collaborate."

Looking forward to further updates... thanks again for sharing!

[timeorspace]

So if I understand correctly this is an FX setup for electric bass? I'm interested as I play some bass... but more recently much more time messing with keys, acoustic, and learning midi coding techniques on the arduino building controllers and small synths. I find the Axoloti fascinating (I'm new and so far have been too busy with other projects to totally dive into the patching thing) but also like seeing the merge of technologies having an Arduino do some of the work.

[Gavin]

In theory the setup is more of a form of multi effect processor for guitar or bass, but as a bass player and it being my tailor made system, I refer to it as being a Bass Effect System. The way I see it, the only thing that will be designed around the bass guitar itself, is how I use the audio captured from the bass for triggers etc, but this will end up defined in the nobjects and patches themselves.
The problem with many proprietry systems (i say many because I probably don't know them all), is they are limited, Prior to finding the Axo, I could quite put my finger on it, but every device I read about seamed to be incomplete for what I wanted, and way overpriced to even consider giving it a go.
On discovering the Axo, and its mostly synth based use within the community, I have discovered that there are ways of manipulating audio that propritory guitar systems are not likely to explore, one main reason I think is because of the time required to set it all up, since getting an Axo, I have found several other devices that could be used in similar ways, like coding the audio for certain outcomes, that are designed for guitar or bass, but they lack greatly on the hardware side and software side, which for the Axo is not only realy good, but is still getting alot better.
In my design I wanted to follow the aspect of what makes a good guitar multi effect system, I spent alot of time reading about other systems, reviewing what I liked and dislicked about the systems I already owned, but mor importantly also needed to ensure I took advantage of the extra resources that Axo has like midi and the flexibility within the on board GPIO's etc.. and it might seem funny, but I needed to ensure I cxould control all of this with my feet. So I creatre a patch by hand on the pc, upload it to the axo where I have the ability to access 32 switches and 32 parameter adjustments all using my feet.
I think in alot of ways I am still messing with keys and midi like you are but, its just re-designed in a way to look more like a guitar multi effect system, but in reality its the same thing anyway.
I have spent so much time on it though, I do envy those who have built simple synth systems with their axo's and having lots of fun with them. My problem is, if I built one, I wouldn't know what to do with it, so I am stuck with what I know, bass guitar..

[Gavin]

More updates...

First picture brings together a basic overview of the full basic build.
Doesn't inlude yet pre-amp, midi sound module (still undecided if this will be added) and room for 2 guitar pedals as part of an addon extra project soon to be started. (Controlling external pedals from the Axo).

The software is completed, this first screen allows you to select the patch to play. 1 of 96, 6 pages of 16 to choose from. What it doesn't show is an additional generic patch setup to choose from for testing projects, that does not link to any specific Axo patch, this is what will be selected for the following 2 pictures after this one.

This screen shows 1 of 2 pages of 16 switches (32 in total) corresponding to each foot switch on the pedal board startibng from the left 2 rows of 8.

This screen shows 1 of 2 pages of 16 parameters (32 in total), each parameter is selected and adjusted based on set values for each switch.

This nest image will help tie all the above together, it shows how the switches are setup on the pedal board and their related function navigating and adjusting. There are 20 switches, group of 16 to the left, and 4 to the right, the 4 on the right are mostly used for changing modes, pages and selections etc.. diagram explains better. The modes in red are to be built at a later date, the aim will be to build an editor that allows me to add text and presets etc using the setup footswitches etc.. instead of the current method of building up text files of data.

[timeorspace]

very nice build @Gavin. Your detailed explanations of the build are really appreciated... this is really cool.

[Gavin]

Thanks, I just wish I could get it right in the first build, never having to review what I have done. I have been thinking lately that to fit in an "Editor Mode" and a "Preset Select" mode, I may struggle with memory onboard the Due, so I am looking to ensure before I go to far, to try and simplify it greatly to avoid these issues down the track. Too much frustration of building and changes, not enough time spent having fun on the Axo. Hopefully it will all work out for the best when its done. But at least the above version is in play, fully working, the new versions can take their time..

[timeorspace]

very well said friend...
all work and no Axoloti play makes any jack a dull boy.

[Gavin]

Update.. 5 x expression pedal system now built and functioning.
Appologies for the slight bluriness. !!

System was built using the same approach that I outlined in the following post..

DIY Expression Pedal Cheap, Simple, Robust

I have been on a journey to find a simple, cheap and robust design for an expression pedal. With a desire to make 5, I did not want to shell out $50 x 5 minimum, so for several months I tried several hackups, and now I can finaly post my final outcome. Important to note, I am keeping the details extremely simple and short with room for all to consider their own alternatives and or addons etc.. Get yourself some Water pipe fittings.. [image] The ones I chose, 2 elbows and a link peice (c…

Photo's..

Slightly disasembled.

assembled.

with the entire system.

Any further build changes will just be cosmetic and or convenient.
So it is pretty much done, and all is fully working, the menu code will require a bit of tidying up to get the best easy to use format.

Some potential addons to come..

• To use the second bank of 16 switches and parameters could be used as a 16 step sequencer. The challenge here is to learn how my goals could be complimented with this. Need to learn different ways how a sequencer could be used.

• The control of vactrols to replace potentiometers via a midi setup to control a matrix mixer and external guitar pedal parameters directly from the Axo.

As soon as I have a performance patch that helps show my intended ghoals, I will post some sounds..

[Gavin]

Final core build is now complete !!
Any changes from here on, are cosmetic, and addons.

First up, the main control panel required a rebuild, had to make more room...

The extra size was required to accomodate 3 controller boards.... (left to right)
Arduino due - Sends midi to Axoloti and drives the display and menu.
Robertsonic TSunami - Wave sample player, polyphonic, 8 outputs etc.. Controlled by Axoloti via Midi.
Axoloti - No description required.. !!

And no build is complete without a jungle of wires...

Here is everything packed up for transport etc...

A basic setup for performing..

Following is an image to help show how it is all set up etc..

With many of my audio cables being old, I decided to build my own to meet the length requires more exactly, save money, and learn some new techniques.
I learnt to make slid elbow jointswith hot melt glue and aluminium foil.
Here is an example of one many made, I have to make a few more for spares etc..