Catalinbread - Dirty Little Secret

[ShortScaleMike]

Knocked this up today from Lawnchair's Schematic. Unverified as yet, any eyes cast over would be greatfully received.

[Seishin]

The mu-amp has been used as a building block for a lot of pedal designs.

In terms of gain stages I like the sound of Jfets second to tubes. The mu-amp arrangement has a BIG benefit in terms of building on scale, first a jfet is cheaper than a trim pot and you don't have to spend extra time tuning from the line and fielding down the road in CS. So it is a great building block for sure.

The DLS was an extension of the Habanero Fetish I made sometime around 2000. Like an idiot I was experimenting with patina of copper I made a copper faceplate for the Fetish and stuck the entire pedal guts and all in the bucket with ammonia. Needless to say the pedal died.

what was the second switch for on the "Hanabero Fetish"?

(Hanabero Fetish, Chili Picoso... you do have a fetish for peppers )

Second switch switched out the second gain stage. The story goes about the habanero is I grew some when I was living in Kentucky, they grow GREAT there better than in Oregon. I had so many I didn't know what to do with them. I cut a few up and made a salsa or something I don't remember exactly. An hour later I went to take a leak and suddenly my junk began to burn to all hell. It really hurt bad and seemed to spread. My girlfriend at the time brought me a glass of milk, I jumped in the bathtub, and tossed the milk on the burning. The pain went away but damn those peppers were hot!

[SPeter]

Many thanks ShortScaleMike !

[Lawnchair]

Knocked this up today from Lawnchair's Schematic. Unverified as yet, any eyes cast over would be greatfully received.

Great Job WKH!

[ShortScaleMike]

Knocked this up today from Lawnchair's Schematic. Unverified as yet, any eyes cast over would be greatfully received.

Great Job WKH!

Sorry for the confusion, I thought Lawnchair had done it. Thanks to you both.

[ShortScaleMike]

Aside from the transistors all being drawn the wrong way round which I will fix tomorrow, my layout is verfied and working. I built it this evening

[RnFR]

hey guys-

whitekeyhole was nice enough to send me his eagle files for the dls, so i thought i would clean up his schem a bit. here's what i got-

[dap9]

Awesome work everyone! I'm having a hell of a time "seeing" the wiring of the Rock/Rawk switch. Can someone draw it out? I get the rest of the schematic, but can't get the image of how that DPDT is wired. thanks

[RnFR]

the way i'm thinking it goes is that sw1a on my schematic is one half of the dpdt, and sw1b is the other. don't quote me on that though.

[ShortScaleMike]

the way i'm thinking it goes is that sw1a on my schematic is one half of the dpdt, and sw1b is the other. don't quote me on that though.

That is nearly correct, they're labelled SW1 and SW2 on my layout with P being the Pole and A/B either side.

From messing with the veroboard I made up yesterday when I had the poles seperate so I could do the "correct" and different combinations, SW2 affects the overall gain and voicing from the oldschool to the newschool whereas the SW1 change tightens up the bass response in the higher gain mode.

Anyway: Verified veroboard layout. Will fit into a BB Hammond Case with ease, not so a Hammond B, I would have to halve the width and make a taller layout.

[Da Cat]

A very very very very very ...... very quick prefboard design, which could use some optimising:
Unverified, please report errors.

It doesn't include 100uf cap for power filtering, which i usualy stick on the DC jack

[Lawnchair]

Cap on gain pot should be 47p no?

[dap9]

the way i'm thinking it goes is that sw1a on my schematic is one half of the dpdt, and sw1b is the other. don't quote me on that though.

That is nearly correct, they're labelled SW1 and SW2 on my layout with P being the Pole and A/B either side.

From messing with the veroboard I made up yesterday when I had the poles seperate so I could do the "correct" and different combinations, SW2 affects the overall gain and voicing from the oldschool to the newschool whereas the SW1 change tightens up the bass response in the higher gain mode.

Anyway: Verified veroboard layout. Will fit into a BB Hammond Case with ease, not so a Hammond B, I would have to halve the width and make a taller layout.

Thanks guys, after staring at it for a while, that's exactly what I started picturing - so thanks for the confirmation

[blanik]

anyone tried to use two separate SPST switches to have the thighter bass with the old voicing? sounds interesting

[Lawnchair]

One of the issues I have with Rawk mode is the lack of low punch. I find rock to be perfect with my setup. Keeping the EQ of rock with the gain boost sounds ideal.

[Seishin]

One of the issues I have with Rawk mode is the lack of low punch. I find rock to be perfect with my setup. Keeping the EQ of rock with the gain boost sounds ideal.

If you have the chance to check out a Silver Jubilee you'll notice something similar compared to a later mid year Marshall like that. If there is one rule you can apply to Marshalls in terms of evolution, as time went by they became more bright and more gainy. As far as gain is concerned they didn't get boneheaded brewtal until fairly recently. I do think the big bass frequencies are starting to come back into favor for Marshalls. Early metal guys like Priest or Maiden goosed theirs with treble boosters, 80's guys used a boss or ibanez object. Different strokes... We limited the scope of the DLS to what we could do with the Marshalls we were working with. Nothing compares to a real Marshall, but I think we got really close for a pedal. Schematic is correct from a quick glance.

I am looking forward to where you guys take the DPDT to a pair of SPDTs. Only reason we didn't go there was for the sake of simplicity.

[dap9]

Thanks Nic for your participation in the thread! I have a capacitor question for ya (anyone else can chime it). The pics of the DLS have ceramic and the Greenies. Are the Greenies any certain brand? And what's the rationale for the choices here. You know, instead of box caps etc. I've read and re-read a lot of stuff on different caps and no matter what I always end up I like the idea of my parts bin having a plethora of styles of caps, but I'd like to no the reasoning for it. Thanks again for everything! dap

[playon]

... and then there was the incident with the Icy Hot...

That reminds me of the time I mistook some Eucalyptus ointment for the lubricant in the dark... the lady was amused, I was not.

[Seishin]

Thanks Nic for your participation in the thread! I have a capacitor question for ya (anyone else can chime it). The pics of the DLS have ceramic and the Greenies. Are the Greenies any certain brand? And what's the rationale for the choices here. You know, instead of box caps etc. I've read and re-read a lot of stuff on different caps and no matter what I always end up I like the idea of my parts bin having a plethora of styles of caps, but I'd like to no the reasoning for it. Thanks again for everything! dap

We use http://mouser.com/catalog/catalogUSD/638/847.pdf Greenies. Why? They are inexpensive, readily available, and sound good. Sometimes ceramic caps are just what you need for a guitar to stand out in the mix... There is a certain graininess to them that helps. However we are working on a deluxe model which will be pretty expensive as most of the $ goes to the artist who lost her job last December, I encouraged her to follow her callings and paint for a living, Catalinbread is her 2nd client! In this model we will be using silver micas for the treble bleed cap and the 470pF. For lack of better words this sounds more "integrated" with the amp and guitar. I don't think it is a better sound perse but it is different. Sometimes the cap type is all there is left to horse with in terms of refining a topology, like a fuzz face, you could make tuning that circuit into a religious experience if you wanted to.

There is a good reason to use the box caps namely uniformity in size. I haven't really gone there cause the price goes up too. All in all our capacitor bins are pretty limited in terms of values and types. I only pick up new types when curiosity gets too big to ignore and new values when we are designing something and have to build values to get to where we need to be. Since we don't sell "parts pedals" as a part of our hook it makes the most sense for us to design around what we already have on hand.

[blanik]

...we are working on a deluxe model which will be pretty expensive as most of the $ goes to the artist who lost her job last December, I encouraged her to follow her callings and paint for a living, Catalinbread is her 2nd client! In this model we will be using silver micas for the treble bleed cap and the 470pF. For lack of better words this sounds more "integrated" with the amp and guitar. I don't think it is a better sound perse but it is different. Sometimes the cap type is all there is left to horse with in terms of refining a topology, like a fuzz face, you could make tuning that circuit into a religious experience if you wanted to...

instead of the "bass cap" switch half, maybe a pot that would pan between two cap values would allow fine tuning (i always find the low frequencies handling of a pedal is the most sensitive aspect of a pedal)