Barber Compact Direct Drive

[jugglindan]

Starting one of these:
https://tagboardeffects.blogspot.com/2014/05/barber-compact-direct-drive.html

Step 1: building a parts list and gathering supplies from my stash (resistors not really shown, as they are easier to grab from my sorted stash as needed):
34500

Just a few values missing. I could either sub the next closest values, or make a trip to Jaycar and get exact matches for a couple of dollars. Without breadboarding the circuit it's hard for me to tell which values are critical and which can be substituted.

[McCreed]

I can't help with any advice there, but it's good to see you're not having any trouble staying busy :D

[jugglindan]

I can't help with any advice there, but it's good to see you're not having any trouble staying busy :D

It's amazing what working from home for the last week has done for my productivity on personal projects!

[jugglindan]

A bit more progress today.
Got the perf board cut to size and marked the locations for drilling to make the cuts in the copper traces (I don't have one of those fancy schmancy perf board cutting tools so I drill from the front with a 1.5mm drill and then from the back with a 2.5mm drill then clean up with an exacto knife):
34513

Except it's a good thing I try to follow the measure 15 times because I don't trust myself, cut once philosopy. Can you see the mistakes?

Fixed and rechecked another 10 times before drilling, cleaning cuts, and testing with a multimeter:
34514

Ready to start soldering components.

[jugglindan]

Missing parts purchased.
Links, diodes and resistors fitted.
34534

[Simon Barden]

Now to cap it all...

[jugglindan]

Now to cap it all...

Yep, caps, op amp socket, and the mids trimpot next. The original circuit has a 9k1 resistor, and tagboard effects give a mod with an external 10k pot. It's the sort of setting I wouldn't change much so I am using a 10k trimpot. I won't be surprised if I end up dialing in something close to 9.1 k :)

It's been a while since I built on stripboard (first stripboard pedal). I had forgotten how much more stressful it is! With a PCB I can at least be fairly sure that a component is in the right place, but stripboard is so much easier to get wrong. All that counting, double-checking and second guessing was exhausting. Gets easier as more components go on though.

PCBs tend to have better clearance between solder pads too. I did quite a lot of continuity checking where it looked like I had accidentally bridged adjacent joints.

Finally, at first I found the solder wouldn't take on the stripboard at all. It just balled up on the lead. I gave the copper a very light sand with 400 wet and dry which fixed it.

[jugglindan]

Board fully populated. In the end the trimpot didn't fit in the board layout, so I fitted a 9k1 resistor as per the original circuit.
The mix of green poly and multilayer ceramics is simply because Jaycar only had the required value in poly.
34551

Next up: sorting out a drilling template, and drilling the enclosure. Then I can do the offboard wiring (sockets, pots, switches, power LED) with all the wires cut to the right length. Only then will I get to test if this works first up, or if I need to enter debugging mode.

After that, the most critical stage of all: deciding what colour to paint the enclosure, and what to call the pedal :)

[jugglindan]

Given this is the first time I have built on stripboard for a very long time, I have learnt quite a bit so far. FWIW:


My old PCB trick of bending the leads over to hold components in place prior to soldering is a very bad idea on stripboard.
- For things close to the edge, sometimes I can use an alligator clip.
- A bit of electrical tape also works.
Continuity testing immediately after soldering a component is a good idea. I found three accidental solder bridges between copper tracks this way and was able to fix them immediately rather than having the issue go undetected until discovering things don't work right at the end.
Triple-check (at least) placement for every component. It's tiring and much slower than a PCB build, but mistakes are so easy to make and hard to undo once components are in place.

[jugglindan]

Today: enclosure prep.

Using a drilling template from General Guitar Gadgets (http://www.generalguitargadgets.com/how-to-build-it/technical-help/articles/drilling-enclosures/) for the first time. Marked out the holes I needed and carefully taped the templates (top and front) in place:
34561

Then checked drill diameters for everything using the conveniently empty case for my OD-2 before centre-punching and drilling everything. Looks OK:
34562
34563

Until I do the mock build. Jacks and pots all fit. It's a bit snug but there's enough room. But there is not enough clearance for the two switches and power LED. That whole row needs to be 10mm lower down (see above re first time using this template):
34564

So I can drill a new row further down and try to fill (unlikely) or live with 3 pointless holes marring the pedal. Ugly and dissappointing.

Or I can adjust the template and drill a new enclosure. Not appealing since the enclosure is expensive.

Or maybe I can just wiggle things in. I am using DPDT switches for the mock build but I only need SPDT which have a narrower body. And solder lug pots might just fit which means ordering some (I was planning to mount the PCB pots onto small stripboards). Or I could go to 9mm pots but that's likely to cost as much as a new enclosure.

[jugglindan]

Or I can bend the PCB mounting pins on the pot by 90 degrees and it just fits. Once I get the SPST switches I think it will work out. Hooray!
34565

But I will definitely adjust the GGG template for next time.

[Andy40]

Yeah, a bit too snug in there, fraught with problems. I usually build first then box after, just my preferred method, very rarely have I got everything to fit the other way around, I really need to see everything first.:)

[jugglindan]

Yeah, a bit too snug in there, fraught with problems. I usually build first then box after, just my preferred method, very rarely have I got everything to fit the other way around, I really need to see everything first.:)

I thought that by using the GGG template that they would have sensible spacing. Once I get the smaller SPDT switches I think I can make it work. If not, then 9mm pots might be required.

We have slightly different build preferences then. I like to drill the enclosure and mostly do the off-board wiring in place so I can get the wire lengths just right.

[Andy40]

Fair enough. I did think of the 9mm pots when i saw those 16 mm ones but I still wasn't sure of the clearance with the jacks positioned there when the jack is in place.

[jugglindan]

Fair enough. I did think of the 9mm pots when i saw those 16 mm ones but I still wasn't sure of the clearance with the jacks positioned there when the jack is in place.

The photos don't really show, but there is plenty of clearance vertically between the 6.5mm jacks and the pots. 125B enclosures have a lot of height. The only clearance issue is between the pots and the switches. My SPST switches arrived today so I will test this evening. Hopefully I will have enough space that I don't have to junk the enclosure.

And I will make an updated copy of the template for next time.

[jugglindan]

SPST switches did help, as did a bit of pot leg bending to get another mm or 2. It's still a tighter fit at the top of the enclosure than I would like, but should be workable so long as I insulate with electrical tape to prevent accidental shorts.
34581
34582

Also got the primer on the enclosure today. Going with a British racing green in keeping with the original.

[Andy40]

Tidy as!

Sent from my Pixel 3 using Tapatalk

[jugglindan]

Tidy as!

Sent from my Pixel 3 using Tapatalk

Hah, you haven't seen my wiring yet! Think "rat's nest" but messier :)

[jugglindan]

Finished the off-board wiring tonight, but still haven't boxed since enclosure isn't ready. Hooked up to the amp and spent 5 minutes wondering why there was no sound at all.

Debugging was easy. I hadn't fitted the op amp into the socket 😊

After that, it works nicely. Didn't spend any time dialing it in, but all controls work as they should

[jugglindan]

the first test:
34599
I haven't soldered the power jack, LED (and current limiting resistor) yet since the jack needs to be wired into the enclosure, so I used alligator clips to a 9v battery.

[jugglindan]

enclosure painted, ready for some clear (when I spray guitar tomorrow) then racing themed decals and more clear:
34601
I took inspiration from some of the old Lotus and other British racing liveries of the 60s and 70s.

[Andy40]

I immediately thought, Aussie Aussie Aussie!

[jugglindan]

I immediately thought, Aussie Aussie Aussie!

Hah, I didn't even think of that. Good thing I have the white stripe :)

I was thinking more of things like these:
34602
34603

Although green, yellow, and white turn out to be my daughter's school colours as well.

[jugglindan]

Decals on. The decal edges are not as noticeable in normal light (I had a powerful desk lamp shining from the left), and hopefully they will be even less obvious once a couple of clear coats go on tomorrow.
34609
Edit: changed to a photo taken in daylight. Legibility still poor over the green, but decal edges not so bad.

[McCreed]

The decal edges are not as noticeable in normal light (I had a powerful desk lamp shining from the left), and hopefully they will be even less obvious once a couple of clear coats go on tomorrow.

With some of the enclosures I've done, I have laid out all the control positions and their labels on one single decal in Illustrator.
Doing it that way puts the decal edge right the edge of the box.
After the decal is completely dry (left overnight) I cut out the pots & switch holes with a sharp pointy hobby knife.

I also print at least 1 more than I need in case I stuff it up and need to remove & re-apply.

[jugglindan]

That's a good idea. This was my first time using decals since the model airplane days when I was 10.

I might be able to do that next time if I am lucky. My printer struggles with the decal paper thickness and it smeared the toner on the middle third of the page. If I am lucky I might get a useable 125B-sized decal on the sides.
34608

[jugglindan]

It's also interesting to me that the decals over dark colours have much more visible edges than over light. Something for me to consider when painting my next enclosures (got at least 3 in the pipeline - compressor, red llama, and buffer).

[jugglindan]

#5 is alive!

Got everything wired in to the enclosure tonight. It's snug, but it all fits (lots of electrical tape just in case):
34680

And done:
34681

Except for the knobs, they are temporary until the decent ones arrive.

It works nicely. It's a more raucous sound than my OD-2, at higher gain settings it gets close to Marshall Guv'nor/plexi territory. Lots of other useful sounds in there as well. Hitting the high gain switch really kicks it up a notch. Tone control doesn't do much but the harmonics switch changes the sound a lot, in a nice way.

[McCreed]

Cool! Looks like the decals bedded in better than the other one, and I actually like those knobs (especially if there were 3 of them ;)).

Shame about the tone control. Can it be remedied with a different value pot?

I've become a huge fan of OD's with 2 or 3 band EQ. Any plans down the track for something like that?

[jugglindan]

Cool! Looks like the decals bedded in better than the other one, and I actually like those knobs (especially if there were 3 of them ;)).

Shame about the tone control. Can it be remedied with a different value pot?

I've become a huge fan of OD's with 2 or 3 band EQ. Any plans down the track for something like that?

Yes, the decals did bed down better on this one. Not sure why as the paint was the same age and I used the same technique. I have noticed that the paint colour affects how the decal edges look. The tone works, but it's not very pronounced. It's a standard hi-cut filter so I might be able to experiment with cap and resistor values, but desoldering components on stripboard is a pain, so I probably wont.

I was planning to build a Guv'nor, but this pedal can (just) get into similar territory so the guv'nor might be a while. Anything with 5 knobs would probably go into a larger enclosure too.

Also, I have more of those knobs but they are for knurled shafts. The only A1M pot I had isn't knurled. I could drill out the knob a little so it fits and then glue it on, but that will make future repairs harder. Maybe just a small spot of CA ...

Next pedal plans are to finish the LHS buffer and build the compressor kit.

[Andy40]

Hey Jug, I meant to ask, how do you mount your PBC in the enclosure so it holds steady and doesn't short? I normally wire the pots directly on the PCB so I don't have that problem but I want to do a vero board project soon.

[jugglindan]

Hey Jug, I meant to ask, how do you mount your PBC in the enclosure so it holds steady and doesn't short? I normally wire the pots directly on the PCB so I don't have that problem but I want to do a vero board project soon.

I don't have an ideal solution yet. I first tried using hook and loop tape from my pedal board. Loop tape inside the lid, hook tape on the solder pads of the board, but the tape adhesive wouldn't stick to the board.

So right now I am lining the inside of the enclosure with electrical tape, lining the exposed pots and any other potential shorts, then just resting the board inside the case with some foam padding between the board and the lid. The tension of the wires seems to hold it in place, nested into the foam.
3472834729

It's early days, but so far this is working. My pedals just stay on my board and don't moved around. If you planned on gigging with them, something more robust might be called for. I have seen others use hot glue to fix the board to the insulated case. Or you could use these (https://www.pedalpartsaustralia.com/index.php?main_page=product_info&cPath=98&products_id=1987&zenid=8255702384c13c6d6633d60420ae8172). I got some in the Julius kit, but they should work with vero builds as well.

DC (jugglindan is just my generic username, DC is my real nickname :) )

[Andy40]

Cool DC,
I've used those stand offs before but not much success on getting them to stick on the inside of the enclosure for any period of time. the foam looks like a better option than electrical tape.

[jugglindan]

I don't have much foam left. It was packing in a box of bathroom taps. But the reject shop sell 3mm yoga mats cheap. One mat would be a lifetime of pedal insulation

Sent from my moto g(7) using Tapatalk

[jugglindan]

A note to my future self: if you ever feel the need to fit a knurled pot knob to a smooth shaft pot by drilling out the knob slightly and fixing it with a bit of CA glue: use less glue! Or better still, stop being cheap and use matching pot styles.

So yes, I did exactly that and ended up with a drive knob that was glued strongly to the pot shaft, and to the enclosure so that it wouldn't turn. Wrenching it with pliers got it turning at the expense of some minor paint damage around the base of the knob. Not going to fix though as it still passes the 2 foot test and now has 3 matching knobs (the black and yellow ones seen above).

[DarkMark]

Nice looking pedal, jugglindan. Horribly, horribly noob question. Does the box need to be made of metal...could it be made out of wood?

[jugglindan]

Nice looking pedal, jugglindan. Horribly, horribly noob question. Does the box need to be made of metal...could it be made out of wood?

1000 posts! Congrats :)
34781

All my pedals are in diecast aluminium boxes because they are readily available in standard sizes. The metal helps them stand up to being stepped on, and provides shielding from electrical interference. On some builds, the metal of the case is used to ground the input and output jacks instead of running ground wires to them. I don't usually do this though as an extra wire doesn't hurt.

If you had the woodworking skills you could definitely put a pedal into a wooden case. You would probably want to shield the interior with copper tape in the same way you shield the cavities on a guitar, otherwise you may get unwanted noise.

[jugglindan]

The more I use this pedal the more I like it. I found some settings yesterday for a light overdrive that seemed to enhance the note clarity and articulation. Notes just leapt shimmering from my amp. Fingerpicked passages had the clarity I had been trying to find for ages. It's early days, and I haven't rebuilt my pedalboard so a side by side is a while away, but this pedal might do the low gain thing better than my Timmy clone. Or maybe just as good but different.

The setting was tone at 2, drive at 10 or 11 and harmonics switch on. With the same settings but switching to the high gain setting I was in a much crunchier world. I wish I put the gain switch onto a footswitch with a second indicator LED. No room now that I have drilled, but if I ever rebox this would be the reason.

[jugglindan]

This build is done :)

I rebuilt my board tonight and this pedal sits just after the OD-2 (so I can kick it up a notch with the boost). If I ever build another boost I will call it the Spice Weasel ("let's kick it up a notch - BAM!"), but I digress.

The more I explore the sounds in this pedal, the more I like it. I pretty sure it has evicted two other drives (the Joyo Sweet Honey and the Caline Pure Sky) from my board. It has more clarity than the Sweet Honey and can do the warm low gain thing just as well with the tone rolled down. It also does the low-gain well-articulated driven chords rhythm thing (if that's a thing) better than the Pure Sky. It makes the Pure Sky sound more like a Low Clouds and Foggy Sky. The only thing the Pure Sky does better is the active EQ (but I can build an active EQ pedal) and can live without that for now.

About the only reason to keep the Pure Sky around is that it sits before the OD-2 and does a good job stacked into it. But once I get the Lemon Squeezy boxed it will be sitting at the front of the signal chain and should easily handle double-duty as a booster.

So all in all, this pedal has delivered far better sonic results than I expected. Very very happy :D

[DarkMatterResist]

@jugglindan Great build and thanks for sharing. I will no doubt be asking questions when the time is right to start this one :) How does it sound? It looks amazing ...

[jugglindan]

@jugglindan Great build and thanks for sharing. I will no doubt be asking questions when the time is right to start this one :) How does it sound? It looks amazing ...

Thanks! After seeing your work on the bass, that's high praise indeed! Your artistic talents greatly exceed my own.

[DarkMatterResist]

Thanks! After seeing your work on the bass, that's high praise indeed! Your artistic talents greatly exceed my own.

Aren't you kind :cool: and don't talk yourself down - you do great stuff too!

[jugglindan]

:D



Obligatory 10 characters. No wait, that's more than 10 but we can edit that out right?

[Simon Barden]

:cool:

I normally just type some rubbish then set the font colour to white to hide it if I only want to do a smiley.

[jugglindan]

Handy tip, thanks.