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What's it being used for?

So it's named Larry?

Does it sound pretty, pretty good?

Although, we might have to only use lead-free solder and solder in a professionally ventilated area to live long. My electronics teacher was like "Don't use the Pb-containing solder, if you want kids without three arms." my answer: "Three arms would be the most awesome thing for soldering!" 

PSA time to allay some of these fears: Lead doesn't vaporize or burn at soldering temperatures, it melts, which is how it ends up on circuit boards. The flux and rosin are much more dangerous and often contain known carcinogens that, in high concentrations, are very dangerous. There may be trace lead particles in the solder fumes, and of course those build up over time, but again they aren't the primary danger. Just don't eat the solder, and was your hands after working, and lead poisoning for a hobbyist will not be a danger. You still want ventilation, of course.

Here's one source:
http://www.lbl.gov/ehs/ih/pdf/safeSolderingFinal.pdf
"Because of the relatively low temperatures in electronic soldering, fumes from these metal constituents themselves are not normally a concern. When solder contains a core of 1-3% flux, appropriate controls should be used."

I'm pretty sure this is similar to the wording in the NASA soldering guidelines, but I'm too lazy to dig through those at the moment.

Again, I'm not saying that ventilation isn't necessary!

Yeah, if you have kids, nephews and nieces, neighbours, or perhaps even friends with kids, get them to paint or decorate your boxes. Or maybe just some of them.

Jacob

Do it. Child labor is the !#$!@.

The 90s super group you never knew. Members of this band went on to play with Paul McCartney, Air, and write songs for Disney.

Jellyfish


https://www.youtube.com/watch?v=eHvgQDRpA-s&feature=youtube_gdata_player

This was cool. Plus, drummer lead singer.

I need the little emoticon of the guy doing the "We're not worthy" bow.

The whole album that's from is on youtube, too.

Look for a used Scarlett 2i2. I've seen them for $100 on the gear page.

[AND neither is a 4001 without a big ole CLR!]

At the very least, you must have a smallish current limiting resistor. About 100R is fine. Most of the time. Note there are a bunch of designs -- even famous ones -- that don't have that CLR and they seem to blow a lot of Zener diodes.

Note that it will also provide some reverse polarity protection. Except that the Zener isn't as robust as a rectifier diode like a 1N4001, and you blow the diode anyway, even with the 100R!

Then there are times when that same 100R, in a current-hungry pedal, will sap a bunch of voltage from the final pedal.

The important thing to remember is that Zeners aren't regulators (don't use them to knock down a supply to the right voltage), and they aren't reverse polarity protection. (AND neither is a 4001 without a big ole CLR!) They are, however, useful for protecting against momentary spikes in power. A regulated supply made for powering pedals (even something like the 1Spot or Powerall) is still better than relying on the Zener.

One last thing: I use a 12V Zener as my overvoltage protection for LT1054s. My one spot never gets anywhere near that, but if it were 9.1V, it would constantly be shunting half a volt, which would heat up and potentially eventually fail.

Scruffie has posted that it's a good idea to have a resistor in parallel with the diode as well. But it's complicated calculating what that resistor's value should be.

Like Jason said, they cause a lot of problems.

If you want to read more in-depth on the subject, it's been covered recently in a DIYSB thread and in a couple threads here, so it might be worth a search.

Can the egghead be run at 18v?

As long as your caps are rated for it. Keep in mind that you won't get more headroom than the diodes can provide. They clamp the signal to 1.2V on one side and .6V on the other, which is well below the power rails, and the second op amp is 2x gain (that's R6/R5), which is still well below the power rails.

If you want to take advantage of higher voltage, I'd suggest adding a switch to go to LED clippers or something.

Congrats on your first build.

My first thought when he approached me was the EM drive.

Barf. Horrible design. But I think I've ranted enough about that pedal elsewhere ...

Seriously, the Egg Head minus the presence control is about as basic an OD as you can find. It's just amplification and asymmetric diode soft clipping and nothing else. If the guy really wants transparency, that's all you need. If you really want to get fancy, you could make a diode switch or something.

Thanks for the feedback!  I really want to put a Fatpants boost in there but he seems adamant about transparency.

Fatpants is "transparent" on the full-range side, and it'll have a treble cut switch or bass cut switch for when he discovers that an actual transparent boost can make an overdriven amp or overdrive sound like crap ...

Brian's Egghead would be fine for the OD side, and I don't think you need anything more complicated. No bass control, but hey, he wants transparent, right? So that means that he doesn't want a bass control. And you can just leave the presence control off, because he doesn't need any tone knobs, because he wants it transparent, right?

That would be a really small 1µf 400v box cap. Smaller than his 1µf 63v behind it.

Wait, you're right. I didn't blow up the picture and thought it was bigger than it is.

I really like the color of that enclosure - do you remember the name PPP uses for it?

Had to look it up—OBD Green. No idea what OBD stands for...

Ole Birdie Dastardly.

My acoustics seem to be pretty picky about what goes on them. My koa Larrivee sounds really hard and tinny with Martins or Cleartones, but Elixirs sound perfect on it. My Tennessee Crafters is the exact opposite ... sounds overly bright with elixirs and perfect with cleartones (or the Martin strings that have the same coating).

My electrics seem to be a little less picky. I was using cleartones for a while because I had thought at some point that the elixirs sounded weird on a couple, but I couldn't really tell a difference when I went back and checked over the winter. So now i'm just using elixirs on them so I can buy multipacks. The Elixirs last longer than anything else (unless you use a pick), so in the end they're the cheapest way to restring my guitars.