D*A*M - Professional Fuzz Sound

Whoismarykelly · Post by **Whoismarykelly** » 19 Feb 2010, 00:16

If you reverse the polarity of all the polarized parts you can sub NPN germaniums right into this circuit. Its not NPN itself that causes the noise, its trying to wire up a PNP circuit as negative ground. OC140 are generally very high quality transistors so your build with them will likely be quieter than a similar build with common PNP devices.

Kollaps · Post by **Kollaps** » 19 Feb 2010, 01:15

Ohh okay--cool! Glad to know these lil buggers are gonna be put to good use then!

phibes · Post by **phibes** » 19 Feb 2010, 04:39

Yeah, give the OC140's a shot.

As far as two ground wires versus one it doesn't matter. The one on the left grounds the input jack which grounds the input wire shield and the one on the right grounds the output jack and the volume pot which grounds the output wire(s) shields. Looks sexier then connecting them together from the input to output jack with the power jack in there.

sinner · Post by **sinner** » 28 Feb 2012, 19:31

Any idea what this 470R resistor it left up corner is for? It's to small for LED limiting, and I see it first time in MK3/4 Fuzz Sounds

sinner · Post by **sinner** » 28 Feb 2012, 21:48

While I'm here, I did the Black On Black Custom version

Few differences, mainly minor resistor swaps, 4u7 ecap in place of 220nF, and that's it

Looks sexy with black satin paint and gloss black lettering. BTW, there was Red On Grey as well, but the spec is the same

I wasn't sure about the pots. The Treble 'n' bass was clearly seen as 100kA, but the other two was mystery to me. On one of the standard mk3/4 shoots I've seen volume pot marked simply as 470kB. It looks like D.Main likes 470k for volume pots, I've seen it in few of his builds... Sustain is just plain guess, at least this is what we have in vintage mk3/4 tonebenders.

The 10n was surprise to me, it's more colorsound powerbooster and overdrive value than standard 1000-2200pF value in mk3/4 benders, but it's clearly marked on one of the picts as 10nK63, so what the fuck other than that it could be?

The *? is also my guess. I'll stick with 220pF in mine, as it's in mk3/4 benders, as well as in powerboosters/od's. The only pict with this cap marked I had is the marking with just plan '5' on it. WIMA do FKP2 series caps had 5 on them, those are polypropylene - bigass 630v's. Look very similar to what is in this puppy, one auction is going currently on ebay BTW https://www.ebay.com/itm/WIMA-Polypropy ... 5ae51519c9

I'll do MK3 and MK4 next

sinner · Post by **sinner** » 28 Feb 2012, 22:13

MK4 attached.

I don't know what mk3 is, to me they look the same

sinner · Post by **sinner** » 28 Feb 2012, 23:31

Here's nice sounding demo of MKIII

The 3 years old kiddo plays on similar level, but at least it sounds nice

[youtube]#![/youtube]

joeboo88 · Post by **joeboo88** » 28 Feb 2012, 23:55

Sinner: your pedals look so sexy, only geeks like us can drool over a bunch wire and stuff

Nice job, your layouts are a thing of beauty too. Keep up da good work!

I need to add to my "stuff sinner says" ~ "Got a vero?"

Ha

beedotman · Post by **beedotman** » 29 Feb 2012, 08:35

sinner wrote:MK4 attached.

I don't know what mk3 is, to me they look the same

There where some units with 680K/100K bias string on Q1 base for sure.

beedotman · Post by **beedotman** » 29 Feb 2012, 08:39

sinner wrote:I wasn't sure about the pots. The Treble 'n' bass was clearly seen as 100kA, but the other two was mystery to me.

In Omeg pots "A" stands for Linear pots, not Logaritmic.

Sustain is 100KA Linear for sure, too.
Volume could be 470K...

beedotman · Post by **beedotman** » 29 Feb 2012, 09:03

sinner wrote:Any idea what this 470R resistor it left up corner is for? It's to small for LED limiting, and I see it first time in MK3/4 Fuzz Sounds

Maybe when pedal is powered by DC jack -9V goes through 470R..?

sinner · Post by **sinner** » 29 Feb 2012, 09:33

beedotman wrote:
sinner wrote:I wasn't sure about the pots. The Treble 'n' bass was clearly seen as 100kA, but the other two was mystery to me.
In Omeg pots "A" stands for Linear pots, not Logaritmic.
Sustain is 100KA Linear for sure, too.
Volume could be 470K...

It could be, Mr.Main says it has lots of volume, he exactly says:

the go fuck yourself volume of a Big Muff

Lovely description

anyway, 470k pot should give some overall gain bump, isn't it?

beedotman wrote:
sinner wrote:Any idea what this 470R resistor it left up corner is for? It's to small for LED limiting, and I see it first time in MK3/4 Fuzz Sounds
Maybe when pedal is powered by DC jack -9V goes through 470R..?

No idea, I was quite busy with other layouts yesterday to hang on it

sinner · Post by **sinner** » 29 Feb 2012, 09:38

joeboo88 wrote: I need to add to my "stuff sinner says" ~ "Got a vero?"

Ha

Yeah, I can't read this whole fucking schemathematic, gimme vero biatch!

beedotman · Post by **beedotman** » 29 Feb 2012, 12:23

Volume pot confirmed

Linear 470K.

beedotman · Post by **beedotman** » 29 Feb 2012, 12:27

And one more.
Since sustain and tone pots has same codes - I think we may consider both as confirmed Linear 100K

beedotman · Post by **beedotman** » 29 Feb 2012, 12:39

And here's another MKIV unit with 20K bias resistor on Q3 collector.

sinner · Post by **sinner** » 29 Feb 2012, 14:59

beedotman wrote:And here's another MKIV unit with 20K bias resistor on Q3 collector.

Yeah, they very from 15k to 20k in different versions. I was thinking the same about the pots, I'll update the file when I'll be back on my main PC - not sooner than day after tomorrow

phibes · Post by **phibes** » 29 Feb 2012, 17:43

The 470R is prolly just for LED. In most it looked like the LED was running directly off 9V. Musta used a different LED in that one. 470R ain't too low.

The volume boost comes from dropping the limiting resistor on the output.

beedotman · Post by **beedotman** » 01 Mar 2012, 07:43

Anybody here have Fuzz Sound and can measure Q3 collector voltage?

I have tried few different transistors as Q3 and I've get very different bias readings - from let say 1.6V up to even 4V with no really big difference in overall sound tone...

agoldoor · Post by **agoldoor** » 04 Mar 2012, 07:43

Hmm... I've built two Fuzz Sounds as well as an straight-up MKIII, but I don't have a real one to measure. But I could take measurements for you of the fuzz Sounds I built if you'd like.

The gains I ended up using were pretty standard darlington pair for Q1/Q2 of around 70. On the second one I built which is more gainy to my ears, I think it's not perfectly matched, Q2 is probably 10 HFE higher. And for Q3, on the first one I built HFE was like 100, and on second one, the gainier one, it was HFE of like 125 actually. Leakages were pretty low all across the board, no more than 200, and my leakiest in Q3.

That was just my experience... I would have to say though, as far as sound goes, I wasn't particularly impressed with the MKIV/Fuzz Sound as it goes for fuzziness. It's a VERY well balanced pedal, but much like the Grease Box, it's a lot less fuzzy than say an MKII, MKI, or even the "early version" of the MKIII that Electric Warrior was so kind to provide me a layout of. My tastes just lean toward the more extreme, I am not one to "dial in" my fuzz to low levels, if you get me?