Vintage Multi-Fx

[JRM]

Hi guys,

I was probably drunk or completely crazy when I decided to build a vintage multi-fx box. But I've started and invested to much money and time to give up. So it's time to hear you on some issues and for some problem solving.

The effects in line: Fuzz Face (silicon BC109 version) -> Cry Baby -> Dyna Comp -> Big Muff -> Power Boost -> Outside Loop (Send/return for additional FX) -> Phase 90 -> Electric Mistress -> Tiny Tremolo. This will have a Korg pitchblack tuner before and a TC Flashback delay after that, along with the Cry baby, are the only bought effects in my chain, as all the others are diy. Cry baby was modded to true by pass and connected to the board in a way that is controlled from it. I play with a Strat (SSS, Texas Special) through a 15W valve Laney Cub 12

Status: I've built a "dummy board" on a cardboard box with similar dimensions of the final box in order to check if things work and to test some solutions/options.
Fuzz Face: done and kicking (I love it); I'm using this circuit http://www.aronnelson.com/gallery/main.php/v/DRAGONFLY-LAYOUTS_0/album18/album151/DALLAS_ARBITER_FUZZ_FACE_SILICON_PERF.gif.html but on a stripboard and with a trimpot to adjust the bias of the 2nd trannie to 4,5V
Cry baby: modded and connected to main board; already found out that the connection wasn't reliable enough and that I'll have to integrate it completely in the board
Dyna Comp: not working. Debugging process ongoing but it's becoming hard. I lose signal on the first trannie. I'm using tonepad's circuit.
Big Muff: works OK (not fully happy with it's sound). I'm using 1973 Ram's head version circuit that I've found in kitrae's website.
Power Boost: works wonderfully! I love it as a Clean Boost. It's a little hard to control to use as an overdrive, specially with my low-power valve amp but it's quite nice.
Loop: checked and working
Phase 90: not finished yet (tonepad's layout)
Electric Mistress: not finished yet (9V with MN3207 version that is on this thread: http://www.diystompboxes.com/smfforum/index.php?topic=78270.140)
Tiny Tremolo: deadastronaut layout that is very simple but incredibly nice sounding

This is all fed by a 9V PSU (this one: http://www.banzaimusic.com/HN-Power-HNP18-090.html).

Photos (sorry for the poor quality):




Doubts/hints needed:
1- I've used cat5 24AWG solid core wire to wire almost everything but the in/out where I've used some spare klotz AC106 cable; This was OK for signal traveling (I do prefer solid core wire either in hi-fi or guitar applications) but it revealed to be a questionable choice as it breaks quite easily; on the other hand, it was free
2 - I have some radio interference and noise that might be related to the poor ground design and specially the poor (actually none) shielding of the signal/+9V/GND paths. I searched but haven't found a way to do this correctly.

[Chugs]

What kind of enclosure are you going to use to house the effects in? How are you going to integrate the wah?

[StereoKills]

I would imagine most, if not all, of the noise will disappear once it is housed in a grounded metal enclosure.

[JRM]

I was thinking to build a wood enclosure as it's much easier for me. I already have the plans made and just need slight changes in order to fit the wah in. One thing that I can easily do is to use some copper shielding sheet on the top of the box (inside).

The wah is integrated easily with four wire feeding +9V/GND and In/Out; +9V/GND are connected to the respective "rails" and In and Out are connected to the 3PDT that enables true by pass for the wah.

Regarding the "rails", I feel that I should really work them out better but I don't have any clue how to do it.

[Le québécois]

I have done exactly that and it work nicely with my Laney cub 10! I have a vox instead of the cry baby but overall it's quite similar. I've decide not to include the wah in the box. Don't give up, you will be happy with the result.

If I can give you only one suggestion: I use wood to build the box but because you want to activate your fx with 3pdt footswitches you need the surface to be strong and resistant. Unless all your Pot and switche were bought with extra long ''neck'', you only have 1/8 inch of space between nuts and bottom (not certain how to explain that better) to mount them on the top of your box. You'll agree that a 1/8 inch thick plate of wood is not very foot resistant! To overcome that I use metal sheet that is stronger for the same thickness. So the border and bottom are made of wood but the top is metal. For increase strength, I've also glued a plate of wood (1/8 or so) below the metal sheet (the metal was gauge 22 I think ... few mm). The overall thickness (wood + metal) was just enough to avoid problem and it is strong .

The dynacomp from tonepad gave my a lot of trouble but it was my first DIY effect. The problem was a solder bridge. The Tonepad layout is very tight look carefully for such bridges.
The bigmuff was remove from my multifx and replace by guvnor.

click here to see my too many knobs box (if it's not working its page 835 of the picture thread)
http://www.diystompboxes.com/smfforum/index.php?topic=36392.16680 

[JRM]

Thanks Le québecois!
You also have a mess of wires! Did you use some shielded wire anywhere?
A metal enclosure was my first plan but it's much more dificult to work with and it's impossible to make a decent cut or bend at home. But it might be a solution for both interference and fitting the pots and 3PDTs.

[JRM]

If I choose 1,5mm Aluminium sheet, do you think it's OK?

[StereoKills]

You'll want to line the rest of the box with a conductive metal tape as well. Wood does not shield very well!

[JRM]

I was thinking of making the box with a 1.5mm thick aluminium sheet instead of wood, not shielding.

[artifus]

stumbled upon this recently: http://www.qrpbuilder.com/downloads/pcb_chassis_a.pdf

[DougH]

Sounds like you've got your hands full.

[Mark Hammer]

Back in the day when things actually were made of wood, a great many "integrated" stereo amps would come in a nice oiled wood box.  Since the signal they were getting from the turntable cartridge was but a few puny millivolts (or less if it was a moving coil cartridge), rather than the few hundred millivolts that come from a guitar pickup, the prospect of applying gobs of gain to that and NOT amplifying stuff that was not part of the music was daunting.

So how'd they shield that sucker?

Generally, there would be a layer of metal foil adhered to the inside of the wooden chassis, with a screw sunk into the box that had a washer with a ground wire soldered on.  The foil surround would be connected to the ground on the circuit board via the washer/wire.

Is standard kitchen foil robust enough for the task?  Maybe.  It would depend on brand.  But electronically, it is good enough.  Another alternative is to find some brass shim stock from an automotive outlet, or similar, and use that.  Just be careful because it can slice your hand VERY easily and leave you unable to play for the rest of your life.

[JRM]

artifus: nice but heavy work! If I thought doing this on aluminium wasn't easy... In fact the only problem with an aluminium enclosure is that I'll have to find out a shop that bends and cuts me the metal. Drilling and painting will be "peace of cake".