Turning irig cable into stompbox

[phd paul]

novice pedal builder here, and what I'm trying to accomplish here is to turn my irig cable into one of those bypass on/off stompboxes for ampitube.
I have both of these:
http://stephenpoff.com/blog/wp-content/uploads/2010/10/iRig-package-for-blog.jpg

http://www.sweetwater.com/store/detail/iRigPre

Wanting to make one of these:

https://www.amazon.co.uk/Stompbox-Guitar-Interface-iPhone-Touch/dp/B007536YJG

I'm looking to add my iPad to my effects loop with a true bypass switch. I have an old 6 pedal amp foot switch that I'm using to house my: tap tempo, eq true bypass, and wah true bypass. I have 3 empty spots and think it would be great if I could incorporate my amplitube app with just a bypass switch, w an led. Looking for suggestions from you pros out there. Guessing I'll need: a 3pdt switch, resistor w led, and a couple 1/4 in. Jacks. This is my first pedal build, so any advice or suggestions are welcome. Thank you

[Jdansti]

Welcome!  I think you're right about the switch, LED, and resistor.  The big question for me would be whether you use the store-bought iRig unit and just plug it into your bypass box, or whether you incorporate them into the box to avoid any extra cables hanging around. One option would be to build your own iRig and put it in the box. You'd use standard short patch cables between it and your other boxes or footswitch loop. The only other cable would be the one going to your iPad. There are a lot of schematics and layouts for the DIY iRig.

[phd paul]

Thanks for the reply! My thought was to use either one of the store bought Irig cables I have and house it in my foot switch. Adapting the headphone out up to 1/4in. jack. I will look into the Diy schematics some more and maybe just start from scratch. Looks like I need to go: male to male trrs from iPad to box, guitar in, amp out. I'm assuming that I will be bypassing the tip of the trrs w the switch? I will research the diy Irig schematics more, just looking for some advice from someone who has done this. Thanks again.

[Jdansti]

I've built a DIY iRig, but haven't housed it in a bypass box. I'll play with some sketches to see how it would work.

[Jdansti]

Here's how I think it would work. You'll have to separate the signal wires from the ground wires on the iRig's input and output cables. 

The battery/power supply would only be used for the LED since the iRig gets phantom power from the iPad. All of the grounds shown would need to be connected together. It probably won't hurt if the battery/power supply ground is connected to the iRig ground since the positive of the supply will be isolated from the iRig.

If you put this in a separate enclosure, then 1/4" jacks would be connected where the signal in and signal out are shown. If you include it in a multi-effects enclosure as it seems you might do, then just connect the signal in and signal out to the places where you want to insert the iRig in the chain.

Edit: Since the cable that goes between the iRig and iPad is hard-wired to the iRig and is very short, you might want to find an appropriate extension cord so you won't have to leave your iPad on the floor.

Edit 2: Added LED resistor.

[Jdansti]

One more thing. I've never used the iRig in series with other effects. Maybe you have and you know how it affects the other effects downstream. You'll probably have to turn the volume way down on your iPad.

[phd paul]

Put this project on the back burner for a bit, totally forgot I posted this. Your schematic looks pretty good. Really appreciate all of your help. I'll give it a shot and post back.

[DanielA]

The photobucket link is down, do you happen to have a copy of the schematics? I wanted to do this myself as well, maybe adding an expression pedal so that I don't have to carry my whole pedalboard around for practice and so on. I don't know anything about building pedals but I thought this might be a project insteresting enough to get into. Thanks and regards.

[Jdansti]

The photobucket link is down, do you happen to have a copy of the schematics? I wanted to do this myself as well, maybe adding an expression pedal so that I don't have to carry my whole pedalboard around for practice and so on. I don't know anything about building pedals but I thought this might be a project insteresting enough to get into. Thanks and regards.

*&^(% Photobucket!

I can't find my schematic, but you can find it here.  http://www.instructables.com/id/iRig-Guitar-input-DIY/

Mine worked fine without the ferrite bead.

There are other schematics and layouts on the web (probably on this forum too).

[DanielA]

Thanks man. I had already seen that one but since the title of the post was about turning it into a stompbox, I thought your schematics might have other stuff like a true bypass switch and so on. Although, I guess that I could try to add a true bypass like here http://stinkfoot.se/archives/2233 and just add a potentiometer for volume. Would that work? Thanks again

[Jdansti]

No, my schematic was just the basic circuit.  I made it as small as possible and heat shrinked it to the cable so it was streamlined.  It would be very simple to put it into a stompbox with true bypass.  You could add a pot for volume.  I could be wrong, but I think if you put the pot on the output of the iRig, you'd have less issues with loss of highs when you turn it down.

[DanielA]

Alright, thanks again. I expect to have some free time in the next few weeks, I'll see if it works