Shure Level-Loc

y-u-no-f800b said:
A very dirty and unique compressor circuit made famous by the Tame Impala guy. Also not a super easy circuit to get your hands on. Here's a link to a lengthy thread of people figuring out a stripboard layout for it in pedal format: https://www.freestompboxes.org/viewtopic.php?t=31204

Would also be nice to have it be stereo?
Click to expand...
Nice to see my thread pop up here!

I ended up getting a PCB fabbed and built a few of these:
PCB Assembled Top COMPLETE copy.JPEG

I also made some PCB faceplates for it:
4 - Carpet Front Tilted GOOD - EDIT Crop CoolTemp.JPEG

I do still use the one I kept, the fast attack & way this thing smashes your sound is unlike any other pedal I've played. The components are actually all pretty common except for the JFET, so it ends up being a pretty cheap build.

I have run into a weird issue that intermittently causes some distortion or instability (especially at fast release times). It sounds similar to how a reversed polarity electrolytic sounds in the audio path, but I've simmed & checked voltages at each cap, and even built up boards with them installed backwards with no improvement. It could also be due to some issues with the output gain stage, where I had to decrease the gain to work with guitar signal levels. Someone else mentioned that it might be due to the amount of emitter degeneration on a few of the gain stages.

The only other thing I can think of is that on my PCB I ran a very long high impedance trace from the sidechain output to the JFET, so maybe it's picking up some interference along the way.

Here is the most up-to-date schematic:
Level Lacquer FET Limiter v3.7 Schematic NEW.png
 
bowanderror said:
Nice to see my thread pop up here!

I ended up getting a PCB fabbed and built a few of these:
View attachment 34764

I also made some PCB faceplates for it:
View attachment 34765

I do still use the one I kept, the fast attack & way this thing smashes your sound is unlike any other pedal I've played. The components are actually all pretty common except for the JFET, so it ends up being a pretty cheap build.

I have run into a weird issue that intermittently causes some distortion or instability (especially at fast release times). It sounds similar to how a reversed polarity electrolytic sounds in the audio path, but I've simmed & checked voltages at each cap, and even built up boards with them installed backwards with no improvement. It could also be due to some issues with the output gain stage, where I had to decrease the gain to work with guitar signal levels. Someone else mentioned that it might be due to the amount of emitter degeneration on a few of the gain stages.

The only other thing I can think of is that on my PCB I ran a very long high impedance trace from the sidechain output to the JFET, so maybe it's picking up some interference along the way.

Here is the most up-to-date schematic:
View attachment 34768
Click to expand...
Saw that on Reddit when I was looking to see if anyone had done it as a pedal before. Looks fantastic!
 
Thanks y'all! This was my first go at making faceplates, but I'm super happy with how they turned out. I'd probably go for a heavier 2oz pour on the faceplates (these are 1oz) as the surface isn't quite as smooth as I would have liked.

I have a few PCBs left, but the layout is pretty tight, even in a 1590BB. I had to really wedge everything in there due to the width of the board. This was one of my first PCB layouts, so I learned a LOT from the process:
SUN Inside Top CROP.JPEG

They also still have that intermittent distortion issue. If I can find a fix for that, I'll gladly share an updated PCB or gerber files.

There are a ton of smart folks on here, I'd love to get some advice on where/what to look at!
 
bowanderror said:
Thanks y'all! This was my first go at making faceplates, but I'm super happy with how they turned out. I'd probably go for a heavier 2oz pour on the faceplates (these are 1oz) as the surface isn't quite as smooth as I would have liked.

I have a few PCBs left, but the layout is pretty tight, even in a 1590BB. I had to really wedge everything in there due to the width of the board. This was one of my first PCB layouts, so I learned a LOT from the process:
View attachment 35281

They also still have that intermittent distortion issue. If I can find a fix for that, I'll gladly share an updated PCB or gerber files.

There are a ton of smart folks on here, I'd love to get some advice on where/what to look at!
Click to expand...
Really great work! And, if you don't mind sharing, what program did you use to design the faceplate?
 
I used Inkscape to design the faceplate, and then SVG2SHENZHEN to output into Kicad. It took me a bit to figure out how the layers created by SVG2SHENZHEN affected the end result, but once I got the hang of it, it was pretty easy.
Level Lacquer Faceplate Mockup.png

If you're looking to give it a shot yourself, I found this Hackaday tutorial, this Modwiggler thread, & this DEFCON talk really helpful. I usually work in EAGLE, but there are only a few steps you need to do in Kicad, so don't worry if you're not familiar with it.

Here are some tips I had stashed away in my notes:
  • Board Thickness - Standard 1.6mm boards are sturdy & will ship quicker, but not all pots & switches have enough thread length to get through both the enclosure & board. May want to go down to 1.2mm or 1mm.
  • Copper Pour - Standard 1oz pour can result in board features & FR4 texture coming through, try a 2oz pour for a smoother look.
  • Surface Finish - HASL = Silver color, but contains lead (not great if you're going to touch the faceplate). Lead-Free HASL = Silver color, but without that sweet, sweet lead. ENIG - Gold color, looks very nice & very corrosion resistant, but MUCH more expensive. Any HASL (hot air surface leveling) finish will look more uneven than a plated finish like ENIG.
  • Remove (or hide) order number - Most fab houses will place the order number in a random spot unless you pay a fee to remove it completely. For JLC, you can specify a place to put the order number, preferably somewhere out of sight (like the rear of the faceplate. Place the text “JLCJLCJLCJLC” on the desired layer & location, and select the option when ordering.
  • Add to PCB order comments: "For panel use: Ignore electrical connectivity, but please prevent scratches” - The folks at the fab house don't necessarily expect you to be making front panels, but are usually pretty accommodating. You may also want to select the “paper between boards” option to prevent scratches during shipping (especially for bigger items).
  • Drilled vs. Milled Holes - JLC lists capability for plated through hole size is “Min. drill size 0.20mm. Max. drill size i6.30mm” - Larger holes are fine, but they won’t be plated, as larger drill sizes & shaped holes are milled rather than drilled.
  • Protective Clearcoat Finish - To keep your surface finish clean & free of fingerprints, a protective gloss coat is helpful. After cleaning boards with isopropyl alcohol, apply a few coats of spray acrylic or lacquer, allowing the finish to dry completely between coats. For a more durable finish, automotive clear gloss is preferred.
Good luck and post your results when you finish!
 
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