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Shipping times have increased quite a bit these last weeks. We are down to about the last 72 hours of home repairs and renovations before our house goes on the market. While I expected to ship a large batch of orders last Thursday, it just wasn't possible. I appreciate everyone's patience once again: very soon this will be over and I can concentrate more fully on madbeanpedals.

If you have not received shipping notification on your order, please be patient. I will have it out A.S.A.P.

There may be a couple of periods of store closure in the coming weeks. Once our house is on the market I'll be fairly limited in how much of a mess I can make here! I may close the store for a week, and spend that time on getting all the new projects ready for release.

The store will definitely close for at least a week when we move from Austin to Tennessee. That will be (hopefully) within the next six weeks. I will try to give as much advanced warning as possible.

Over the next couple of months there will be many, many new projects released as well as a few new manufactured boards.

This is what I use:

Metalized Film (box) for 1n - 470n, and for 1uF if appropriate
Ceramic for all pF values
Xicon High Temp or mini electrolytic caps.
Mix of metal, carbon film, and carbon composition.

You can absolutely mix any types together. It just depends on what you have available and what you feel like spending money on.

any plans to offer up some simple mods/values for all the different versions of the Meathead?

Sure. Actually, I'll need to do a little reading up on it first because I know that there are a number of variations. I'd be happy to take a look into it and add some mod stuff into the project docs.

A ceramic will do fine.

http://www.mouser.com/Search/ProductDetail.aspx?R=140-50N5-470J-RCvirtualkey21980000virtualkey140-50N5-470J-RC

I always use SPDT. You can leave the third lug unconnected, or you can run the wire from the middle lug to the third lug and solder it. It's a little more elegant that way: no floating/unconnected lugs.

C11 isn't necessary. It's something I added in as additional filtering for PS. But, it was really overkill, so I decided to remove it. You will sometimes see parallel caps for filtering, usually a large electrolytic and a small film or ceramic. The idea is that mixing the two values and types can better filter DC ripple from an unregulated power supply. But, since almost everyone uses regulated power supplies now (or battery) it isn't a big deal. It certainly doesn't hurt, but you won't miss it.

The change from 10uF to 1uF tantalum could influence the tone a little. Not so much from the value, but there probably is a nominal difference in sound between electrolytic and tantalum. Personally, I never use tantalum because they are less stable and tend to fail more frequently than the other. But, some people do like the "sound" of them. If you want to switch C7 out for the 1uF, then go for it! Just be sure you orient it the right way because they will fail if put in backwards.

You could try a few other opamps if you have them handy. My favorites are LF353N, NE5532 and TLC2272. And with the other mods I suggested you might find something you like. Or, it may just not be for you. I sold my ver.2 OCD because I thought it was a little dark for my tastes, but I found that I missed it after a while so I built one. I actually used it quite a bit on some sessions for my band. When I listened back to it later, I was like "yeah...that was just the right effect for that part". Also, I don't know what you are playing through, but Fuller does tend to voice his stuff for Marshall amps. Originally I was playing one through a Vibrolux, and never really bonded with it. But, once I plugged it through my friend's 18W Cage amp, it really came alive.

I prefer the Chunk Chunk over the Kokbox, I think. They are fairly similar in terms of 'architecture' but the CC just feels like...putting your head through a cement wall.

Actually, the 'presence' knob in the CC adds a LOT of extra tonal possibilities.

There are a few other high gain projects coming soon. Most notable, the 'Daytripper' which is my pedal version of the Vox Nightrain amp. It's not as high gain as the two above, but it has a lot of that good j-Fet compressed-saturation gain going on with the Vox feel.

The jack is grounded through the enclosure. It's usually only necessary to ground the sleeve of one jack because of this. If you use the ones with plastic casings, it i a good idea to ground both sleeves.

Hmm, well having built this one a couple of times, and having owned ver.2 I can say that overall, the circuit is a little more bassy and dark than other OD's. With v4 of the OCD, C3 (my schem) was changed from 100n to 68n to help lighten it up a bit. I have not tried this particular change.

Anyway, the HP/LP filter (normally) will alter the tone some, but it also should have a pretty big volume jump. Given the big difference you are noticing, you could make some alterations to suit your taste. I'm assuming that you have have double checked that you have used the correct values for the caps and resistors. You can try lowering the value of C8 to 22n. This will alter the frequency range of the tone knob some (less dark) and also decrease the amount of low pass filtering generated by the R10/R11 and C8 combination. You could also try increasing C3 back too 100n to somewhat balance out the previous changes. At 68n, the feedback loop is applying gain in the 1k+ Hz range, whereas at 100n it brings it down to around 720Hz, which is more midrangey.

Try these out and see what you like. Also, if you are not using the TL082, try getting one at Radio Shack. A TL082 is a noisier version of the TL072. Fuller's choice of this particular op-amp is curious, and from what I've read some suspect that noise actually get perceived as more harmonic content in a weird pyscho-acoustic way.

Let us know what you find!

Sounds like the positive and negative terminals were connected directly together.

That's usually what causes that kind of thing.

Most likely I will not resume tinning for a while. This is mostly a time consideration. While the tinning solution is expensive, and it is an extra service that I don't charge for, the reality is that the process is rather time consuming when multiplied by 40 or 50 boards (or 100!). This propagates into even longer shipping times, and since I'm already having a difficult time keeping up it's something that will have to wait until I'm moved into my new workshop in a couple of months.

However, the boards are always polished with #000 steel wool and cleaned thoroughly with Acetone before sending them out.

I basically soldered circuits from layouts and got a 77% grade for the whole year.

That already puts you in the 99th percentile amongst boutique builders

Yes, add a 10k resistor across lugs 3 and 1 and you should end up with about 5k.

Hi Andy,

Orders usually take around 5 business days to ship. I have a large batch of boards which I am finishing off today. I expect to ship some orders later today, and all remaining orders tomorrow.

Brian

Actually, it's not my method at all. It's the one suggested by Skreddy over at diystompboxes a few years ago. It's really simple: when the switch is in the 'down' position (ie fx is bypassed) the fx input is grounded through the middle column of lugs and the input is connected directly to the output. When the switch is in the 'up' position, the input is taken to the fx input, and the LED comes on because it is grounded through the far left column of lugs. On the right side, the fx output is connected to the output jack.

The three grounded lugs are all connected, although they don't have to be. The advantage of connecting them together with wire is that if the switch ever fails everything remains grounded through that hardwired connection.