geo fxrack inspired project *99% finished*

[mikey]

I came across some 21in x 12in vinyl covered sheetmetal and some small pieces of aluminum recently and decided to build a multieffects enclosure for my brother.  It's not finished but I thought I'd share...



Here's a bottom shot of the easyvibe mounted on one of the 3x5 aluminum faces.  I used metal spacers and some epoxy to hold the board on.  More than enough room to mount it above the 3pdt switch.  You can see one of the spacers popped off the sheet.  The sheets are really smooth so I need to rough up spots before I apply the epoxy.

[Dave_B]

Bravo, Mikey.  That's a great way to make a really tight pedal board.  Any ideas for 'end caps'?

[Mark Hammer]

VERY  nice.   Good work.  The format permits a lot of flexibility in patching (those short patch cables are sweet!), and seems to accommodate a wide array of boards.  You could probably even adapt Dano pedals in there if you felt like it.

I suppose the biggest challenge is providing pristine power to the whole thing.  Another challenge (though less daunting) will be keeping the signal in adjacent boards under the cover plate from "bleeding" into each other.  Keep in mind that when you normally stick a chorus pedal after your fuzz, the clock in the chorus is shielded from straying into the fuzz gain path by not one but two metal chassis. Here, there may be shielded above and below, but not necessarily beside.  In which case some strategic thinking and neat layout is called for.  Judging from what you've shown here, though, you're obviously up to the task.

As well, the delightful modularity of it calls out for quick and easy substitution of modules, much like those old Yamaha and Korg systems.  In which case a socket or header for power connections will be essential.

Just as an aside, Dean Hazelwanter might have something for you (or rather, your brother).  Tell him I sent you. 

[R.G.]

Mikey, you do really, really good work! That's beautiful!

Any ideas for 'end caps'?

One thing that works really well is to take a piece of wood and cut it so it sticks inside the "C" rail bottom by about 1/4", making one for each end. Then take two larger pieces of appearance wood larger than the ends. Glue or screw the inside piece into the outside, appearance piece so that the appearance piece is entirely visible at the end. Finish the appearance pieces nicely, and run screws through the C rail into the inside pieces.

Like this, with glue between them.

Inside piece            -->    =================
Appearance piece    -->  ===================

[mikey]

Thanks.

Any ideas for 'end caps'?

Yeah I'm not sure yet how to handle the ends.  I had planned on cutting some wood to a soft contour of the box but larger in the back to slope the enclosure a bit and use some 90° angle brackets rivetted to the inside bottom of the enclosure and screwed into the sidepieces.  I think it would be sturdy enough but if not I'll do like R.G. said and shape some wood along the inside for extra support.  Some 1/4" ply bound to 3/4" pine would probably do the trick  I'll attach a thin piece of sheetmetal or some aluminum tape to the inside of ends too and block as much rf as i can.

I suppose the biggest challenge is providing pristine power to the whole thing

I have a 12.6v 1.5A transformer wired to a LM317 at 9.1v ready to be boxed for power.  I originally planned to use the first aluminum face to hold the PS but it caused way too much noise that close to the circuits.   I plan on wiring a 2.1mm jack negative to the chassis and the positive in a neighbor style chain where each effect would have a male and female socket of some kind on the wire for +9v.  The male would plug into the female of the effect to its left leaving its own female socket open to power an effect installed to the right.  Makes for easy (re)moving.  I dont know if they'll be any noise or power issues from that setup but we'll see.

Another challenge (though less daunting) will be keeping the signal in adjacent boards under the cover plate from "bleeding" into each other

Hmm ... I had considered that briefly but I didnt think it would be an issue.  I figured on putting a f0XX Tone Machine next to a CE-2 in the chain so that gives me a good oportunity to test.

[Mark Hammer]

One solution to the noise bleed challenge is maybe to just use a piece of shim bent at right angles to form a kind of U-channel that forms a "wall" between adjacent modules.  The shim is thin enough that it can simply be held up against the face plate by the pots, jacks, etc.  I use copper shim stock for internal shielding in these nice plastic Pac-Tec boxes I use (because I get them for $2 surplus locally and they're a good size and machine easily) in a similar fashion.  The nice thing about the shim stock is that you can usually just poke the appropriate-sized holes in them with a hand-held paperpunch - the very same you use for putting pages in a binder.  Also nice is the fact you can cut it to size with ordinary scissors.

[Peter Snowberg]

 

Beautiful work!

[mikey]

From right to left...

Ross Compressor->Tube Screamer->Thunderchief->f0XX Tone Machine->Eazyvibe->Chorrral Chorus->

I'm undecided what the last pedal should be.  I wouldnt mind some suggestions actually.

I had some ticking from the 'vibe coming through the FTM and thunderchief.  At first I thought it was bleeding from the lack of shielding between pedals but it turns out it was coming through the power chain so I made a filter board with a 100r / 100uF / .01uF filter for each pedal and the problem was solved. 

Now I'm having an interesting issue with the chorus.  I get a clock tick if every pedal is bypassed or the chorus is the only pedal engaged but if any other pedal is engaged the ticking goes away ... I just dont get it.

There was some serious tone sucking but after some debugging I found out it was a pair of patch cables.  After I finished each one I ran a diode test to check for shorts but I didnt do an ohm test... big mistake.  After redoing a few plugs I had my treble back.

I still haven't made sides but they're not far down on a very short list of things left to do.  They should be done by next week.

[Seljer]

I guess the logical thing would be a delay pedal on the end there

[mikey]

The final pedal wouldnt necessarily have to be the last in the chain.  I can move them around easily enough.  I had thought about putting a rebote 2.5 on the end but I decided on building a PT-80 which is 18v and something I'd want in a separate box.  Let me see if I can narrow down what I want...  I'd like another distortion or fuzz that has a good contrast to what's already on the board.  Another ROG circuit wouldnt be a bad thing.  Maybe the english channel.

[Processaurus]

Wow, thats totally cool.  I've been thinking about RG's article, its so inspiring to see someone put in the time to make it happen.  Such a good idea, especially for performers, its much more compact and robust than a pedalboard.  You obviously have a good amount of skill, so you may have thought of some of these or decided against some of them, but I thought I'd throw some ideas I had out there, just because you got me excited about this fx rack notion. 

I'm pretty sure the clock noise thing is crosstalk from everything being true bypass, and the high impedance guitar signal cumulatively going through a bunch of unshielded wire (to go through the switching for each effect) in the same box with the chorus.  The same thing came up in this thread.  I would fix it by, rather than using shielded cable for every wire that could potentially carry the unbuffered guitar signal, making a simple buffer for the input (the GGG JFET buffer sounds very nice to my ears), this would have the benefit of driving all the cables and connections in your rack (and a long cable to the amp if everything is bypassed) better without any treble loss from cable capacitance, getting rid of the clock noise, or any other less obvious crosstalk from the other bypassed effects.  If it were my thing, I'd put the buffer in the Ross Comp module, between the input jack and the bypass switch, and have it on all the time (my Ross has this, because its alway first in line, and mine sounds brighter with the buffer in front).

You may actually be able to just get away with using a shielded wire for the input to the chorus, and maybe a copper "hood" for that effect like Mark suggested, but the buffer may improve sound in other respects. 

Some other ideas:

how about a handle, for carrying around with one hand?

For the module that is undecided, how about a true bypass loop, to bypass everything in the box in one click?  If you like both the buffer idea and the loop, you could incorporate the buffer in the loop module. 

Your cables look good for this purpose, and your project is looking pretty done, but if anyone else tries this, one could make a default routing of the effects by using normaled jacks, and some kind of connector for internally hooking them together, but still preserving the modularity.

For power, if you wanted to be done with it and weren't averse to buying something, the 1spot switching adapter from visual sound might work well, it has a real long (10') heavy cord, and can put out 1700mA.  For distributing power, a daisy chain might be better than 2 jacks for each effect.  You could even make your own (mouser has some cheap cables with 2.1 on one end, and bare wires on the other), and rather than a daisy chain, tie all the ends together at the power supply, for star grounding.

Once again, inspiring work!

[Processaurus]

OR, the spare module could be just a simple channel switcher for the amp, if your bro has one that uses a footswitch.

[mikey]

I'm pretty sure the clock noise thing is crosstalk from everything being true bypass, and the high impedance guitar signal cumulatively going through a bunch of unshielded wire (to go through the switching for each effect) in the same box with the chorus.  The same thing came up in this thread.  I would fix it by, rather than using shielded cable for every wire that could potentially carry the unbuffered guitar signal, making a simple buffer for the input (the GGG JFET buffer sounds very nice to my ears), this would have the benefit of driving all the cables and connections in your rack (and a long cable to the amp if everything is bypassed) better without any treble loss from cable capacitance, getting rid of the clock noise, or any other less obvious crosstalk from the other bypassed effects.  If it were my thing, I'd put the buffer in the Ross Comp module, between the input jack and the bypass switch, and have it on all the time (my Ross has this, because its alway first in line, and mine sounds brighter with the buffer in front).

A standalone buffer on the first pedal is an excellent idea even if there wasn't a crosstalk problem (all that reading at the Cornish site and it completely slipped my mind!).  The whole thing is so compact it's easy to forget how much wire there actually is between the guitar In and amp Out.

how about a handle, for carrying around with one hand?

I was checking out the keystone instrument handles at mouser a while back.  Thought about mounting one on each end of the enclosure, more for looks than function.  I dont see this one doing much travelling but for anyone who builds something similar and gigs with it, an amp style handle on the back would be nice to have.  It's so light though you could carry it around by one of the patch cable loops with one finger.

For distributing power, a daisy chain might be better than 2 jacks for each effect.  You could even make your own (mouser has some cheap cables with 2.1 on one end, and bare wires on the other), and rather than a daisy chain, tie all the ends together at the power supply, for star grounding.

The way I have it now is a standard 2.1mm kobiconn jack in the back grounds to the chassis and +9v goes into a filter board with separate filters for each effect. Then wires go out from the filter board and connect up to each effect via an insulated crimp on male/female pair. All effects ground from the chassis through their IN jack.

OR, the spare module could be just a simple channel switcher for the amp, if your bro has one that uses a footswitch.

That's a clever idea.  I dont think his amp has a footswitch though.

[Dave_B]

That's a clever idea.  I dont think his amp has a footswitch though.

Does it have multiple inputs (like a Bassman)?  If it does, you could run a cable to each input and switch between them.

[mikey]

That's a clever idea.  I dont think his amp has a footswitch though.

Does it have multiple inputs (like a Bassman)?  If it does, you could run a cable to each input and switch between them.

It's an old junky Crate.  I'm going to set the condition that he cant have the effects until he gets a better amp.

[mikey]

Finished!


power filter & distro




leds


Well this thing is about as finished as it's going to get.

From right to left: Ross comp->Tube Screamer->Thunderchief->f0XX Tone Machine->Green BMP->Chorrral Chorus(CE-2)->EasyVibe

You cant really see in the pics, but the sides tilt the whole thing forward a bit and lift the chassis off the floor enough to fit cable under so it's easy to patch in other effects in front of the board.

I still need to add an input buffer and labels but I gotta say this thing is sweet. All my concerns about building so many effects into a small enclosure have been laid to rest. I dont hesitate to build another.  Gonna be hard to part with but luckily I have enough of the same materials used in this one to make a few more!   

Big thanks to GEO, Tonepad, GGG, Fuzz Central and ROG for the layouts.

[MartyMart]

Fantastic !! really nice job

MM

[pyrop]

Real nice pro looking job.
Good work mikey.

pyrop

[Mark Hammer]

A thing of beauty.  The power-distribution is lovely.

Now, are you ready for the "Do you think you could build me one?" requests when you trot it out publically?

[Nashtir]

great work man!just 2 questions
1: how did you bend the aluminium and took the right measures?
2: Why didn't you usa a daisy chain for the pedals?what's that pcb (connected to the dc jack)useful for?