Jerash constructions

[rmouneyres]

Album by rmouneyres
Gallery category: members-gallery

All constructions related with Midibox projects

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01 soudure mainboard

laying out part ready to solder :
here the core module
also there is one AIN module

02 assemblage boitier 01

after soldering the two pcb, wiring everything inside

02 assemblage boitier 02

another view of the inside finished
I haven’t populated all the sockets on the core module as i don’t need them. But the LCD was used for testing so its related components are here

02 assemblage boitier 03

global view, just before closing the case
you can notice the old aluminium plate i’m using. The 10 faders come from a cannibalized equaliser unused for many years… it now comes back to life midiifed

03 boitier1 fini 01

closed box with colours /public/style_emoticons/default/smile.gif" alt=“smile.gif”>
for decoration, I used printable stickers, and then covered with transparent adhesive for long term protection.

03 boitier1 fini 02

backside of the box, you can notice there is only one midi (out) connector.
The box is powered with +5V DC from a GM5 circuit powered via USB…

03 boitier1 fini 03

top view, finished, and working !

01 061220121074

button board using MEC 3F switches

01 061220121075

button board using MEC 3F switches

01 061220121076

a nice tip to fix the pcb without holes and screws : super glue !

01 061220121077

01 071220121078

metal work

01 071220121079

metal work

01 071220121080

adding LCD and cable to the button board

01 071220121081

metal work

01 071220121082

metal work

01 071220121083

metal work

01 071220121084

metal work finished !

01 071220121085

test footswitches integration

01 081220121086

01 081220121090

first try… working… but buttons not in good order.. software hacked

01 091220121091

metal painting

01 091220121092

metal painting

01 091220121093

metal painting

02 13122008

metal painting

02 13122008001

rear sticker

02 13122008002

top sticker

02 13122008003

top vinyl stickers

02 13122008004

lacquer

02 13122008005

something missing… the relay board and the rear jacks

02 13122008006

the top looks finished isn’t it ?

02 13122008007

the top looks finished isn’t it ?

02 13122008008

the rear too

02 13122008009

the total is awesome

02 13122008010

waiting for the relay board, the jacks are mounted

02 13122008011

and the software is debugged

02 14122008013

view of the DOUT modules with shunted resistors to drive the relays board

03 301220121108

the relay board has arrived and has been soldered !

03 301220121109

the relay board has arrived and has been soldered !

03 311220121110

the relay board is finished !

03 311220121111

the relay board is finished !

03 311220121112

the relay board is finished !

03 311220121113

the relay board is mounted !

03 311220121114

the relay board is connected !

04 311220121116

this is a real situation test…or a real mess

05 311220121118

finished midibox guitar fx pedal looper switcher

05 311220121120

finished midibox guitar fx pedal looper switcher

05 311220121121

finished midibox guitar fx pedal looper switcher

05 311220121122

finished midibox guitar fx pedal looper switcher

05 311220121123

finished midibox guitar fx pedal looper switcher

05 311220121124

finished midibox guitar fx pedal looper switcher

05 311220121125

finished midibox guitar fx pedal looper switcher

05 311220121126

finished midibox guitar fx pedal looper switcher

05 311220121127

finished midibox guitar fx pedal looper switcher

[technobreath]

Re: 05 311220121121

Oh yeah! Looks good! I have been working on similar stuff, just now and then, nothing serious yet. I’m building one, but not sure yet it’s gonna have midi, but then again, it would probably be stupid not to! Does it work well?

[rmouneyres]

Re: 05 311220121121

hey, thanks !

It works really well, i’m also happy with the menu handling on the LCD. I’ve added a relay board with ULN2803, which need documentation.

For me MIDI is very usefull because I mostly command the pedalboard with automations from Ableton Live. The footswitches are only use when practising new songs

I’ll soon share my code project based on MIOS.

[technobreath]

Re: 05 311220121121

cool.

[technobreath]

Re: 05 311220121121

What kind of relays are u using? I have some thoughts about switching noise - like noise from connecting / disconnecting the FX pedals into the chain. How do you handle this?

My thought was to make a digitally controlled mute circuit at the end of the chain - that is - before signal enters amp or DI box. And mute the output for the split second it takes the relays to switch…

Have a strong suspicion that circuit for this muting or other way to do it can be found in schem for several of the common stomp boxes out there. Especially thinking of the boss tuner - which I know can do silent mutes.

[rmouneyres]

Re: 05 311220121121

I’ve read a lot of information from various website projects before choosing. A lot of information came from a french collaborative project of www.techniguitare.fr They made a similar project from wich i inspired, and adapted it to the midibox and add some features like buttons switching, and grouping…(to be detailed)

I’m using Omron G5V-2 for audio switching and G5V-1 for relays/buttons switching. They are driven by an ULN2803 for efficient switching.

These relays have been proven to work great on audio switching by the users who built the above mentioned project. So after building it myself i can confirm :

The relays do work silently !

Most of the audio clicks come from the pedals themselves when they are connected to the audio path. So it is important to verify, especially for non-buffered pedal (true bypass), that it exist some resistor on the input to absorb the generated clicks. I had problems with a EHX mini Qtron and I had to modify it. All other buffered pedal worked without problem for me.

Also from what i’ve read and understood the ULN2803 (see the picture of relays board in this album) is giving the relay a kind of voltage boost when switching to guarantee fast transistion, and thus less rebound. Too much boost would shorten the relay life, just enough would help. I’m sure that many highly priced commercial products do use the same mechanism.

As all drawing I’ve seen to reduce these noises, are acting on how the relay need to switch, I don’t know about any other improvement “after” the relay.