In my quest to create my ideal portable pedalboard I've decided a Morley Mini Volume pedal is perfect for adding volume functionality to the finished product. The idea is to just use the circuitry in a new enclosure so as to avoid unnecessary routing and cabling. I had lofty goals of completing some projects for work and on our house today, but unfortunately I feel like I'm about to die, so I'll do something that requires less effort and decipher the schematic. First thing's first, tear it apart:
It's a very simply constructed pedal. It's not even a fully enclosed box or cast aluminum or steel as many are, but rather a formed piece of sheet steel with a bottom cover. Four screws hold the bottom in place. After removing the screws it's easiest to remove the battery cover and reach inside to pull the base off. It's a very tight fit, so it takes more force than I was initially comfortable with, but nothing broke, so I was good.
The wide open space of an optical volume pedal. From the factory
it featured a foam battery holder and 9V terminal. I tore them
out the first time I opened it since I always power it with a
9VDC power supply.
The next step is to remove the outer nuts from the in/out jacks and the nuts that hold the pcb in place. A socket or wrench for both are necessary unless you're too lazy to walk across the room to the workbench so you just grab a pair of pliers and go to town. That works too. Then with a little bit of finesse and some prying on the case you can remove the entire PCB in one piece.
Evidently in order to save money on production costs Morley uses the same board for all their mini pedals. They offer a volume/wah combo, as well as a dedicated wah. This PCB has two sets of LED/photovoltaic sensor combos, although only one is in use. Once I discovered this I started formulating how to incorporate a switch onto the body of the new enclosure that would allow me to switch between acoustic and electric volume. Basically in position 1 the acoustic would be full volume while the electric is controlled through the top bank of LED/photovoltaic sensor, and in position 2 the electric would be at 0 volume while the acoustic is controlled by the lower bank of LED/photovoltaic sensor. This will allow me to start at 0 volume on both signals, fade the acoustic in to full volume, hit the switch, and then have the electric. If I decide to have the option of fading the electric in I will need another switch that would mute it while I move the pedal back to the 0 position, then reengaged the signal and fade up. I'm not sure that's an option I'll want to use because of the amount of space needed to add two more switches on the final enclosure. Regardless of what I decide, there are two sets of LEDs:
They shine through these slots and illuminate the photovoltaic sensors. A lot of reviewers online complain that this pedal is either all on or all off. This is because of the design of the holes. They're shaped similar to a hammer, a long skinny 'handle' and a large open 'head. When the 'head is in front of the LED, all the light is allowed through, where the 'handle' section limits the amount of light. I'm thinking that this could be remedied by tapering the opening more and then adding a small piece of translucent tape. I'm not unpleased with the control of the unit, so I will not mess with any of it unless I find myself frustrated with it, or am really, really bored one day.
The circuitry of the volume pedal is insanely simple. Below left is the top (pedal side) of the board, and below right is the bottom side:
In it's simplest explanation, the LED is constantly powered by either battery or a 9VDC power supply (when the pedal is powered on, through the switching input jack). The ground is common for both input and output jacks, as well as the LEDs. The tip (hot) side of the input jack runs to one side of the photovoltaic sensor while the tip of the output runs to the other. The amount of light that reaches the sensors adjusts the amount of signal that passes through from 0-100%. As I said earlier, the second pair of LED/sensor is unused. Here is the schematic I drew up to help get it all clear in my mind:
Now don't focus too much on the wildly beautiful hand drawings that make up this little beauty, because you'll miss out on all the wealth of information it has to offer. What it lacks in complexity it makes up in simple straight forward information. If you'll notice that I've already noted where I intend to steal the signal to send to and and receive from the iRig Stomp. This was originally penned when I intended to just house the guts from the iRig in the enclosure of the Morley. Since I intend to house it all in one enclosure, there will be no need to grab the signal from the input of the Morley since I will simply rout straight from the input jack of the enclosure to the iRig, and then from the output of the iRig to the side of the jumper leading to the sensor. The only reason I will use the jumper is simply because it will be easier to solder there than elsewhere. If I decide to add the switching option for the acoustic signal I will just jumper on the in/out to the bottom photovoltaic sensor and use either a 3PDT or 4PDT switch to handle the signal routing.
Hopefully the coming weeks as I mull over the final product I'll be able to find a few more ideas/shortcuts to make the whole thing work a little better or more polished. Anyway, this is a teardown and reverse engineering of a very simple little volume pedal. I'm hoping that you'll find the confidence/desire to tear into some of your stuff and make it a little more perfect for you...
I love my iOS devices. There was a time I didn't. About the time that the iPhone 3G was becoming available, I was up for an upgrade. I looked into every smart phone that was offered at the time, but each one fell short. I finally realized that the only thing stopping me from getting the iPhone was the fact that it was an iPhone. I was so afraid of falling into the stereotype of Apple fanboy that I avoided their products like the plague. I then realized that mentality was just as short sighted and stupid as those who only purchased Apple products. I now use my iPhone 4 for more tasks than I would have ever imagined and my iPad (which I thought was completely absurd at it's release) is an essential part of both my music making, my other businesses, and my everyday life. I even recently caved and bought a MacBook Pro after my water cooler in my desktop PC exploded while we were on vacation.
So I've loved the idea for years of incorporating the processing power for digital music of the iOS devices into not just recording, but live performances. There have been several products released over the past few years that are pretty incredible, but always left me feeling like there was a big part missing. The initial offering for guitar interfaces (the IK Multimedia iRig, Peavey AmpKit, etc.) were all astonishing in their reproduction of sounds, but always left me with that stupid little 1/8" headphone jack for output. Not at all useful if I wanted to run into a PA.
Griffin Technology previewed the Stompbox a while back and I thought I was sold, but again I was left with what felt really cheap and awkward for interfacing with a PA. A few even managed to incorporate a 1/4" jack, but the impedance was always wrong.
Digitech debuted the iPB10 to accept the iPad and although it was an incredibly cool concept, it's $400 price point coupled with the fact that you must dedicated a device costing at least $500 puts it's minimum cost at just shy of $1,000. Really? A grand for some digital effects?
I watched devices come and go and although I'm still pretty excited to check out Mackie's DL1608, I'm not sure I'll be able to afford it.
Then I saw a preview for the IK Multimedia iRig Stomp. It contained an upgraded circuitry from the iRig (which received less than stellar reviews from most users, though I suspect that was more a result of their software and less the hardware), but was packaged in a stompbox format and included a pre-amp, headphone jack, and not one, but two 1/4" line level outputs. It seemed like I'd found my answer. Then it was a waiting game. I watched as my favorite retailers promised ship date after ship date. I waited and waited. Marked them in my calendar, and then waited some more.
It's important to understand why I want the iRig stomp to work so badly. I run a strange setup for my guitars. A few years back I added a D-TAR Wavelength pickup to my Taylor T5 in order to be able to run dual outputs, an acoustic signal, and an electric simultaneously. I often perform alone and I wanted the added depth of sound of running the twin signals. I started with a little box and added one here and there until I ended up with this:
I then needed a way to transport it, so I came up with the set up you see on the left. It was just a spare suitcase we had with custom inserts I designed to hold all of my other accessories I needed on the road. The pedalboard consisted of a Zoom A2.1u for the acoustic signal, a Zoom G2.1u and a DaneElectro Fish & Chips for the electric side, a couple of signal routing pedals I built, a tuner, and a TC Helicon Voicetone Harmony G for vocal affects. It was a nice little setup, but I wanted a few other things. The empty space on the board was intended for a Boss RC-20xl. Then Boss released the RC-30 and I bought one. I quickly discovered that the looping capabilities were severely limited by the two available footswitches and needed a second interface. Boss's offerings were sufficient, but I wanted to choose when to rout my electric signal through the looper, so I designed another pedal to fill my needs. That presented a problem. I was out of room. Then I decided I needed a TC Helicon Voicetone Correct XT, and I was REALLY out of room. So I built this:
And I love it. It does so many things. I love explaining it to people. I love playing through it. I love watching all the pretty flashing lights when I plug it in. What I don't love is carrying it. Fully loaded in it's box it weighs just over 150lbs. It BARELY fits in the trunk of my car. I designed it to fit, but didn't count on it weighing so much. It's great when I'm traveling through the summers and playing for 3 or more days at the same venue. It's not great for setting up to play a 7 song set in a church service. It's too much. It's too heavy. It's too flashy. I want something that gives me most of the functionality, but much less bulk and weight. Enter the iRig Stomp.
After months of waiting, I finally ordered one of the first available and received it a few weeks ago. I sat down with it, plugged it in and marveled at how horrible the sounds coming from it were. I then did a little bit of reading, discarded the Amplitube software and downloaded Peavey's AmpKit, and I was in love. After about $20 worth of app purchases, I had the sounds I wanted, both from the acoustic side and electric. So now I needed two, and two iPhones (I can steal my wife's on stage right?), and I needed to be able to control the volume of the electric so I can fade it in and out depending on the song.
My main rig has a Morley Mini Volume pedal on it. It's so compact for a volume pedal at about 6 3/4" x 4 1/2" compared to an average size of 10" x 6" for full size volumes. I decided that two iRig Stomps, another signal switcher, and a Morley Mini Volume would fit the bill. I could put it all on a board about 7" x 10" and have about 60% of the functionality of my main rig, but at a fraction of the size and weight.
I can't leave well enough alone. my brother-in-law needed help moving the in/out jacks on his Morley Mini Volume, so I tore into mine to see what I could find. I found that there was a ton of space in there, possible even enough to fit the internals from the iRig Stomp into (I had, of course, opened mine up as soon as I received it to inspect the guts). I started working on the layout and was shortly led to the conclusion that I could, within a larger enclosure, fit all the components for all four of the desired pedals. The design of the Morley lends itself very well to alternate placement. I will show all of this in more detail in future posts as I go through the build. If I cut out all the cabling necessary to rout the signal chain through the 4 pedals, I save enough money to pay for the enclosure. I found several boxes from Hammond Manufacturing that would work, but I think I've decided to build my own out of sheet metal. Regardless, here is the mockup:
Notice I have labeled a midi jack on the back side. That will be my interface with another box I will build that will house/mount/power/interface with the two iPhones. Basically I will use any 8-pin din connector and corresponding cable I can find.
It's just a theory at this point, and will likely undergo massive changes before completion. I still need about $150 to buy the rest of the components and since I do all my music experimentation with our 'extra' money, It'll be a while before that happens, but please check back from time to time to see how things are or aren't progressing.
The next step is to remove the outer nuts from the in/out jacks and the nuts that hold the pcb in place. A socket or wrench for both are necessary unless you're too lazy to walk across the room to the workbench so you just grab a pair of pliers and go to town. That works too. Then with a little bit of finesse and some prying on the case you can remove the entire PCB in one piece. 
