OpenEffectsProject

[onkartgromt]

Hi,
My name is Oyvind and I am new at this forum.
Right now I am making a project aimed at those that is into DIY. It is called OpenEffectsProject and is currently funded through Indiegogo: https://www.indiegogo.com/projects/open-effects-project-guitar-effect-pedal/x/4623729#home


It is a platform where you can insert analog plug-in cards that has a certain function like a VCA, VCF or other voltage controlled modules. Then you can patch wires where you want inside the box to get the effect you want. You might compare it with the Moogerfooger concept, but in one box.
I will also make a "cookbook" with some standard effects like: tremolo, compressor, autofilter, chorus and flanger.
Everything will be open source and open HW so it is possible for all to change, reproduce and add modules to it. At the moment it is still early in development, so there is not much code available yet..=)

My goal is to get enough money funded to produce this box in a larger scale. That way the price can be comparable to a standard effect, but still so much more.
Another important aspect is that the box must be so rugged that it is possible to bring on the next tour..=)

Let me know what you think of the idea...

[amptramp]

It sounds a bit like this project:

https://www.kickstarter.com/projects/deviever/console-ii-cartridge-based-multi-fx-guitar-pedal?ref=email

where you plug in cartridges similar to old-school game cartridges.  The standardization of the quantity and values of pots can be a major challenge.  Buffers and boosters really don't need pots.  EQ pedals would need three, but various numbers are needed.  You might be able to add preset pots to each board for setting once to a value you want.  If you are doing this for your own use only, do what you like, but there have been efforts to standardize before and they have run into these practicalities.

[onkartgromt]

The difference from the Console project is that this is not that standarized. And the intention is that this should act more as a development platform, but still be able to be used on stage.
I will make a "standard" software with tap tempo, LFO with various shapes and so on. This can be used with both a VCA, VCF and VCD. But probably needs some modifications to get it "perfect" for each purpose.
And it is a small job to develop new plug-in cards compared to make a new box each time you want something else. This can be done by all  as it is open source.
regarding the values of the pots in analog circuits, I plpan to use voltage control of the parameters. That way many potmeters can be used, some logaritmic and some linear. But the value is not that critical.

But I think the console is a good idea also. But its a shame that it didn't come to life as planned..

[amptramp]

It sounds like you have addressed some of the major issues with the Console program.

I think there is a market niche for stompboxes that can have parameters set by external or digital control using multiplying DAC's (available everywhere - DAC08 etc.) or digital pots (not that common but still available) and settings set by stepping through the parameter list then setting each parameter.  Not many people change settings during a gig, so this would offer some protection from accidental control changes at the cost of making it more difficult to make changes on the fly.  If you want to set an equalizer to compensate for the room acoustics, it may be a bit more trouble than a normal EQ but if you have certain settings for a phaser, it is not likely that you will want to change them.  The other issue is you need to maintain a non-volatile memory which means a PROM somewhere in the system.  The whole thing could be animated by a PIC since it is unlikely you would need more processing power but I am sure some people will start making noises about, "Well, if you are going this far, why not MIDI?"  But you can ignore them.

For each digital pot function, you will need a display showing where it has been set unless you want a setup for the blind (and then you need a speaker telling you the settings!).  If you don't like drilling holes for pots, I guarantee you will not like hogging out rectangular holes for displays.  It is preferable to have the digital logic stop when the settings are achieved to avoid getting digital chatter on the signal.  I assume this will be a rackmount system since that is more suitable for a development platform, but it could be a classic pedal design.  It would be interesting to see how much additional circuitry would be required to make a 2-transistor Fuzz Face work.

[onkartgromt]

As it is now, there is room for an Arduino Nano that have enough AD inputs. And it is very easy to program and set up a programming enviroment.
And actually... it is made ready for  MIDI for those who want it.
But an issue you adress is the indication of where a potmeter is set. As it is now, I only use standard potmeter. Then it is only an issue if you make presets(which is likely). But you can make it in a way that you must turn it to the actual preset point before it changes value.
A rack system is nice, but I want it in a stomp box. Will use most SMD components in the plug-in card to minimize board size. So a fuzz face should be possible.

[amptramp]

If the Arduino is not to your satisfaction, you may have space (3.37" x 2.21" x 0.83") for a Raspberry Pi.  I am not a big fan of programming or program debugging, so I might use a PIC or random logic version.  It all depends on how advanced you want to be.  For the purpose of controlling presets and pot positions, you don't need much.  But a Raspberry Pi would allow an Ethernet connection and you can get into all kinds of systems design for remote reconfiguration of circuitry.

[onkartgromt]

I think a raspberry pi will be too much and increase the level of knowledge needed to program it too much. But there is a board that is named Teensy3.1 that could fit. It can be programmed lika an arduino , but have a lot more power(arm). so it could also be used for some digital effects. And it has 2 DAC also.
The goal is after all to make a platform that is easy to get up and running for a wide usergroup. And at a reasonable price.
I don't think a ethernet connection is needed at this point, but I have a socket for wireless com that could be used with a  handheld device to control parameters etc. That could be used to free the player from the box on stage and so on...
But it is not in the plan to make that handheld device at the moment. But if someone wants to do that, just start!

[Gus]

Have you looked at GEOFEX?
search for fxbus, fxbmod

[onkartgromt]

Yes it is in the same field.
Have some of you used the fxbus setup and can share some thoughts around it?