freestompboxes.org

Thanks!

Now corrected as detailed below

Thank you both so very much for this !

When I saw R7 was only 120r in the schematic, I had to check the photographs.
It seems Mark really did use a rather low value for the limiting resistor.

Cub wrote:Thank you both so very much for this !

When I saw R7 was only 120r in the schematic, I had to check the photographs.
It seems Mark really did use a rather low value for the limiting resistor.

Yea, it was weird. Totally threw me off for a minute or two, but it's definitely correct. Anyways, I did cock up one value. The collector resistor on Q3 should be 18k, not 15k. About to start a clone layout, so I added a mids DIP switch to the schem. Omit it and the two related caps for the stock circuit.

Nice work!
Cannot wait to get this one going.
Mark uses a pretty sweet selection of caps for this one... lots of ceramic in there

All resistors are 1/2 Watt carbon comp except for power supply intake and LED current limiter.

All .1uf' caps are multilayer ceramic. They sound like the oldschool ceramic discs that aren't made any longer. The .1uf ceramic discs you can get generally aren't as full sounding.

The 120R resistor inline between the sustain pot and Q2, normally 8.2k, permits a more trebly and aggressive sound when you turn the pot to max. Kinda like a secret setting. Very cool. Note: the original Mayonaise did not have ANY resistor here at all (seemed redundant to me at the time, so I designed it to carry the signal straight from the cap to the base of Q2).

Yes R18 is 33k not 39k (as corrected by the 2nd schematic).

Note C4 and C6! They're .22uf instead of the normal .1uf. Why? C4 adds more bass, and then C6 clips more bass, resulting in a creamier tone while maintaining a neutral eq footprint (the additional bass is converted to fuzz rather than left in the signal).

Note: Matt and Mark
It's considered proper to either entitle or annotate your schematics with something that suggests that this is a derivative work as traced BY YOU in order to avoid representing your work as if it were actually mine. It may or may not be 100% accurate, but it's still best to differentiate your work from that of the person whose design is being traced. That's why most clone schematics have made-up names given to them instead of the original trademarked name. That's not absolutely necessary, but it is good to at least mention that this is not an actual Skreddy Pedals schematic.

Skreddy wrote:All resistors are 1/2 Watt carbon comp except for power supply intake and LED current limiter.

All .1uf' caps are multilayer ceramic. They sound like the oldschool ceramic discs that aren't made any longer. The .1uf ceramic discs you can get generally aren't as full sounding.

The 120R resistor inline between the sustain pot and Q2, normally 8.2k, permits a more trebly and aggressive sound when you turn the pot to max. Kinda like a secret setting. Very cool. Note: the original Mayonaise did not have ANY resistor here at all (seemed redundant to me at the time, so I designed it to carry the signal straight from the cap to the base of Q2).

Yes R18 is 33k not 39k (as corrected by the 2nd schematic).

Note C4 and C6! They're .22uf instead of the normal .1uf. Why? C4 adds more bass, and then C6 clips more bass, resulting in a creamier tone while maintaining a neutral eq footprint (the additional bass is converted to fuzz rather than left in the signal).

Note: Matt and Mark
It's considered proper to either entitle or annotate your schematics with something that suggests that this is a derivative work as traced BY YOU in order to avoid representing your work as if it were actually mine. It may or may not be 100% accurate, but it's still best to differentiate your work from that of the person whose design is being traced. That's why most clone schematics have made-up names given to them instead of the original trademarked name. That's not absolutely necessary, but it is good to at least mention that this is not an actual Skreddy Pedals schematic.

Whoops. I almost always put a traced from unit #xxx on my schems. Fixed below.

Thanks, Matt. Also, R13 is 100k as per usual (most folks would just assume this, but your schematic is missing the value).

Anyone know how to alter this layout to be a Mayonaise MKIII?

If I was you and you already made the cival war layout... I would keep it as is
And then make another one using IvIark's layout

On another note... look at the schematic above and make the needed changes

+1 Just print out the sabro layout and the MKIII schematic and trace the vero layout from input to output, writing the mayo values on the sabro layout.

I am going to order a madbean mudbunny PCB and use the Skreddy Mayonaise MKIII values and with my quad of SE4021's
Should more or less come out PRIMO -
stay tuned!

jalmonsalmon wrote:I am going to order a madbean mudbunny PCB and use the Skreddy Mayonaise MKIII values and with my quad of SE4021's
Should more or less come out PRIMO -
stay tuned!

The values are absolutely non-remarkable and will produce nothing more than a generic effect. The parts types, as specified in my earlier post and as pictured by the OP, are the things that give it its particular 1971 character. I mean, yeah; just the transistors would be an upgrade to any modern BMP. But take it all the way, and you'll really be happy with the result. (You'll likely have to run some of the resistors standing up to get them to fit the Mudbunny layout, which looks like it assumes 1/4 Watt metal films, if you use the correct 1/2 Watt cc resistors.)

Here's my layout (not verified, but I'm 99.99999% sure it's good). Note, absolutely zero commercial use allowed. If I find anyone selling these, I'll fly to your house and kick you in the nads. And you may or may not find yourself in trouble.

A few notes pertinent to the build:

Use the schematics linked to on the OSHPark page.
The board is designed to be used in conjunction with my 3PDT daughter board, which holds the main filter cap
Caps are all spaced for TDK FK28 MLCs, but any standard 5mm spaced caps should fit
Transistors are original SE4021s, but you can use anything really. Just check the pinout



Muff - https://oshpark.com/shared_projects/js3WRmMT
Switch - https://oshpark.com/shared_projects/Buk2PeKO

Skreddy wrote:

jalmonsalmon wrote:I am going to order a madbean mudbunny PCB and use the Skreddy Mayonaise MKIII values and with my quad of SE4021's
Should more or less come out PRIMO -
stay tuned!

The values are absolutely non-remarkable and will produce nothing more than a generic effect. The parts types, as specified in my earlier post and as pictured by the OP, are the things that give it its particular 1971 character. I mean, yeah; just the transistors would be an upgrade to any modern BMP. But take it all the way, and you'll really be happy with the result. (You'll likely have to run some of the resistors standing up to get them to fit the Mudbunny layout, which looks like it assumes 1/4 Watt metal films, if you use the correct 1/2 Watt cc resistors.)

Snap... that is true, hmmmm I know those 1/2w cc resistors are not going to be easy to put in a mudbunny so I think I will modify a stripboard layout instead with the correct parts. Thanks Mark!
btw I have one of your Lunar Modules... Absolutely a fantastic FUZZ bar none!

mmolteratx wrote:Here's my layout (not verified, but I'm 99.99999% sure it's good). Note, absolutely zero commercial use allowed. If I find anyone selling these, I'll fly to your house and kick you in the nads. And you may or may not find yourself in trouble.

A few notes pertinent to the build:

Use the schematics linked to on the OSHPark page.
The board is designed to be used in conjunction with my 3PDT daughter board, which holds the main filter cap
Caps are all spaced for TDK FK28 MLCs, but any standard 5mm spaced caps should fit
Transistors are original SE4021s, but you can use anything really. Just check the pinout

[ Image ]

Muff - https://oshpark.com/shared_projects/js3WRmMT
Switch - https://oshpark.com/shared_projects/Buk2PeKO

What's the lead spacing for those resistors? 12.5mm is what you'll want for 1/2 W CC's.

Skreddy wrote:

mmolteratx wrote:Here's my layout (not verified, but I'm 99.99999% sure it's good). Note, absolutely zero commercial use allowed. If I find anyone selling these, I'll fly to your house and kick you in the nads. And you may or may not find yourself in trouble.

A few notes pertinent to the build:

Use the schematics linked to on the OSHPark page.
The board is designed to be used in conjunction with my 3PDT daughter board, which holds the main filter cap
Caps are all spaced for TDK FK28 MLCs, but any standard 5mm spaced caps should fit
Transistors are original SE4021s, but you can use anything really. Just check the pinout

[ Image ]

Muff - https://oshpark.com/shared_projects/js3WRmMT
Switch - https://oshpark.com/shared_projects/Buk2PeKO

What's the lead spacing for those resistors? 12.5mm is what you'll want for 1/2 W CC's.

10mm I think. Was as big as I could go in a 1590B. Might redo it in a bit with 12.5mm.

mmolteratx wrote:

Skreddy wrote:

mmolteratx wrote:Here's my layout (not verified, but I'm 99.99999% sure it's good). Note, absolutely zero commercial use allowed. If I find anyone selling these, I'll fly to your house and kick you in the nads. And you may or may not find yourself in trouble.

A few notes pertinent to the build:

Use the schematics linked to on the OSHPark page.
The board is designed to be used in conjunction with my 3PDT daughter board, which holds the main filter cap
Caps are all spaced for TDK FK28 MLCs, but any standard 5mm spaced caps should fit
Transistors are original SE4021s, but you can use anything really. Just check the pinout

[ Image ]

Muff - https://oshpark.com/shared_projects/js3WRmMT
Switch - https://oshpark.com/shared_projects/Buk2PeKO

What's the lead spacing for those resistors? 12.5mm is what you'll want for 1/2 W CC's.

10mm I think. Was as big as I could go in a 1590B. Might redo it in a bit with 12.5mm.

Or make then stand-up and use a 125 for extra height.