madbeanpedals::forum

Projects => General Questions => Requests => Topic started by: murdog47 on April 19, 2012, 07:27:24 PM

Title: Skreddy P19
Post by: murdog47 on April 19, 2012, 07:27:24 PM
Killer Pedal


Title: Re: Skreddy P19
Post by: irmcdermott on April 19, 2012, 07:31:31 PM
i think skreddy posted the schematic at FSB with everything but the diode types listed out. Maybe I'll give a layout a go. Or I'm sure someone else can beat me to it.
Title: Re: Skreddy P19
Post by: raulduke on April 20, 2012, 07:26:13 AM
Its a tweaked big muff. From a quick look at the schematic you should be able to build it on a Madbean Mudbunny PCB no problem.

I have this and the Pig Mine schem Skreddy posted to build in the future; his muff's are the best without a doubt.
Title: Re: Skreddy P19
Post by: murdog47 on April 20, 2012, 02:37:40 PM
You right! Just put the schematics side by side. Looks like I have another board to order!
Title: Re: Skreddy P19
Post by: raulduke on April 25, 2012, 05:05:24 PM
The only difference I can see is the cap across the tone pot lugs on Skreddy's schematic. But you can put the Cap on the lugs of the pot itself and you are good to go.

I have a Skreddy Pig Mine and its by far the nicest muff I own. Skreddy guy seems to know that circuit, and how to get the best out of it, to a higher level than any other builder IMO.
Title: Re: Skreddy P19
Post by: DutchMF on April 25, 2012, 07:48:56 PM
Quote from: raulduke on April 25, 2012, 05:05:24 PM
its by far the nicest muff I own.

Says the guy whose getting married......  ;)

Sorry raulduke, this was too good to let slide. Big difference between Fuzzes and women: one you own and learn to control, the other you'll never own and never control completely..... (Nor should you want to!!)

Paul
Title: Re: Skreddy P19
Post by: raulduke on April 25, 2012, 07:58:52 PM
I was waiting for the muff jokes ha ha ;D

Title: Re: Skreddy P19
Post by: murdog47 on April 25, 2012, 08:21:13 PM
I've got a Mudbunny ordered to build with the P19 Schematic. I'll let you know how it goes. Greg from Greg's guitar lessons in the video I posted is a friend so I'll see if I can set up a shoot out video to post.
Title: Re: Skreddy P19
Post by: culturejam on April 25, 2012, 08:23:46 PM
I don't know, guys. I like Skreddy and all, personally. But that sounds like a "just a Muff" to me.

Don't take my opinion for much, though. I can't hear night-and-day differences between a Ram's Head and a Triangle version. So maybe I'm the wrong guy to weigh in.  ;D
Title: Re: Skreddy P19
Post by: murdog47 on April 25, 2012, 08:28:30 PM
Quite a difference in person. You tube doesn't do it justice. It's very smooth.  ;D
Title: Re: Skreddy P19
Post by: murdog47 on April 29, 2012, 11:09:39 PM
So I'll start out by saying I'm still really new at this  ??? I've tracked down several differences between the Mudbunny and the P19 and wondering if these make a difference and if I can replicate these differences on a Mudbunny board.  Here it goes.....

R1 on Mudbunny is omitted on the P19 Schematic (Leave empty?)
C11 on the P19 is not present on the Mudbunny Schematic (Add? If so, where?)
C4 and R8 on the Mudbunny Schematic is reversed on the P19 schematic (?)
C8 and a switch (on/on?) are added on the P19 that are not on the Mudbunny (?)
R25 on the P19 (between Tone pot and C12) not present on Mudbunny (?)
R23 on the P19 is not present on Mudbunny (?)
C18 on the P19 is not present on the Mudbunny (?)
D5 and R24 on the Mudbunny are reversed on the Mudbunny (?)

I would like to build this as close to Skreddy's specs as possible but not sure how to make these modifications.  Any help would be greatly appreciated  ;D

(http://i1077.photobucket.com/albums/w466/pmurray47/schematic-1.gif)
Title: Re: Skreddy P19
Post by: raulduke on April 30, 2012, 08:48:26 AM
C18 can be added on the volume pot across lugs 3 and 1.

C11 can be added across the gain pot lugs 3 and 2.

I would not worry about the switchable tone capacitors; just socket the relevant cap on the mudbunny board and pick your favourite.

D5 is for power protection and will not affect the tone of the pedal. R24 is a current limiting resistor (no affect on tone).

D5,R24, C15 and C22 are all for power protection/filtering; I would just use the standard mudbunny parts for this part of the circuit.

If you are new to pedal building I would suggest building one of Madbeans stock projects on a Mudbunny first and then work your way up to building a modded version to match the P19 (his mayo clone that you can build on the mudbunny is a damn fine pedal).

Good Luck!
Title: Re: Skreddy P19
Post by: murdog47 on May 01, 2012, 02:48:36 AM
Awesome thanks! So what exactly is the purpose of the caps across the pot lugs?
Title: Re: Skreddy P19
Post by: raulduke on May 01, 2012, 07:54:38 AM
No problem.

The one across the tone pot is to preserve a bit of treble as you turn down the gain. It is whats known as a 'treble bleed' capacitor. This is V handy in big muff's IMO if you want to use them at lower gain (where they can be traditionally a bit 'muffled' for want of a better word  ;) ).

The one across the volume pot reduces treble (the cap goes to ground); it forms a lowpass filter. This is handy at the end of an effect to reduce 'fizz' and hiss. You can see small caps to ground before volume controls on the loads and loads of schematics.

Good luck with the build mate!
Title: Re: Skreddy P19
Post by: murdog47 on May 01, 2012, 02:31:16 PM
Looks like the switchable tone caps are the same capacitor? Am I missing something?
Title: Re: Skreddy P19
Post by: plesur on May 01, 2012, 03:00:16 PM
Quote from: murdog47 on May 01, 2012, 02:31:16 PM
Looks like the switchable tone caps are the same capacitor? Am I missing something?

One way is one 6n8 only, the other is two 6n8 in parallel = 13n6
Title: Re: Skreddy P19
Post by: Sigesmundninja on May 01, 2012, 04:34:15 PM
the switch doesn't pick one or the other, it picks between one or both. So in one position you have 6.8Nf and in the other position you have 6.8 + 6.8...

damn...  wasn't fast enough! :P
Title: Re: Skreddy P19
Post by: murdog47 on May 01, 2012, 10:46:33 PM
That makes sense  ;)
Title: Re: Skreddy P19
Post by: murdog47 on May 06, 2012, 12:01:13 PM
(http://i1077.photobucket.com/albums/w466/pmurray47/schematic-1.gif)

Anyone know why the R22 and C5 on the P19 schematic are reverse from the C4 and R8 on the Mudbunny? The resistor is before the capacitor in Skreeddy's circuit and the cap is before the resistor in the Mudbunny. Does this make any difference?