Skreddy - Mayo

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Beedoola
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Post by Beedoola »

what happened to the layout?

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Beedoola
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Post by Beedoola »

double post.

Thanks for the layout Nokaster. I built this with 2N5088s from Mouser, I also got some BC239s which has have a less intense flavor. I really, really like the sound of this. I'm gonna get some 2N5133s from Small Bear and see how it sounds.

Thanks a lot. :applause:

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Post by Beedoola »

I seem to be experiencing some noise that sounds like a grounding issue. There are two grounds in the Layout I used - the one Noakster posted. Is there any special way to wire this? I have ground near S1 & S3 going to the 3DPT switch and the other ground on the other side of the board going to input & output jacks as well as the dc jack.

If I do have it wired correctly, is there anything I can add to the circuit to cut on the noise?

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Post by mattpas »

Beedoola wrote:double post.

Thanks for the layout Nokaster. I built this with 2N5088s from Mouser, I also got some BC239s which has have a less intense flavor. I really, really like the sound of this. I'm gonna get some 2N5133s from Small Bear and see how it sounds.

Thanks a lot. :applause:
The 2N5133s from small bear have very low HFEs and won't really work in the Mayo.
It is going to be tough to find any that have 300 HFE or higher.
I used BC239s and it sounded great.

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Post by Beedoola »

Yes, I found that the 2N5133s from Small Bear were too low of gain. I have the BC239s which are nice but I used 2N5088s which I think sound super thick and awesome.

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Post by Whoismarykelly »

You might also consider buying 20-30 SE4010s from small bear and selecting the highest gain ones.

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Post by SpencerPedals »

I definitely just ordered some 2N5133's from Small Bear just prior to checking this board out. Haha. I guess I have my priorities in line for next time. I'll give them a shot and see how they sound anyway I guess. I can always try to find something to use them in down the road. I'll be placing an order with Mouser soon so I'll be sure to grab some of the suggested transistors in the past few pages here. Thanks to everyone that posted their choices, btw. I look forward to building this one; I'm a big fan of the Pumpkins-style thick fuzz.

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Post by Whoismarykelly »

I finally settled down and built up a Mayo on a GGG board with mostly the same stuff as I found in my legit Mayo and for some reason was actually surprised when I plugged it in for testing to hear that it actually sounds like the Skreddy. I used three Fairchild 2N5133s and one SE4010. All four transistors were around 300-400hfe. The other parts were either the same as in the Skreddy or close substitutions. I didn't have a tropical fish for one of the caps and I used the Kemet box ceramics where the Skreddy used Xicons. The only tricky part was having enough transistors to chose a very few that were high enough gain. I've built with the lower gain ones and they dont saturate at all. They make for a cool sound but its not really a muff in the end.
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Post by 95strat »

What type of resistors are those? And brand of box caps? I'm interested in building a Mayo. Hmm. Nice build by the way.

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Post by TheLemon »

95strat wrote:What type of resistors are those? And brand of box caps? I'm interested in building a Mayo. Hmm. Nice build by the way.
I believe they are Carbon composition resistors and Kemet box caps (stated above).

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Post by RnFR »

the 2n5133's small bear sells may not be perfect for a muff, but i have found that they sound great in other fuzz designs. it's still a very nice transistor.

does the SE4010 have higher gain?
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Post by 95strat »

TheLemon wrote:
95strat wrote:What type of resistors are those? And brand of box caps? I'm interested in building a Mayo. Hmm. Nice build by the way.
I believe they are Carbon composition resistors and Kemet box caps (stated above).
Are they NOS resistors? I guess that's what I was really after.

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Post by sfx »

Nope, those are available at any of the big guys; Mouser, Digikey, etc. Just look for carbon composition resistors.

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Post by Whoismarykelly »

I dont know if AB or other companies ever made 1/4 watt carbon comps but those are xicons. The Ohmite ones look like the older kind of that matters to you. The caps are kemet box ceramics, a couple AVX and a panasonic film. The SE4010s come in about 140hfe. I bought a big bag of 2n5133s a while ago and only got about 20 above 300hfe and good enough for a muff. I really ABed the two in the photo above earlier. The Skreddy uses an extra 4700pf cap in parallel for his flat mids and I just used 5600pf caps in the tone stack for flat mids. The mids are flatter in the clone and still a little scooped in the Skreddy. The Skreddy is a little bit woofier which is not a bad thing. The clone cuts a little better and is slightly tighter. When you swap back and forth, the differences are pretty minimal.

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Post by 95strat »

In case anyone wants another guts shot here's a Mayo that been "Pinked" up for auction: https://cgi.ebay.com/Skreddy-Pedals-Pin ... 1|294%3A50

I would love to buy a PF, but will have to build one since they are so overly priced now.

If anyone looks at the pic can you tell me what the big yellow cap is? According to the schematic there's only one electrolytic cap, but that yellow one looks like an electro as well?

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Post by SpencerPedals »

95strat wrote:anyone looks at the pic can you tell me what the big yellow cap is? According to the schematic there's only one electrolytic cap, but that yellow one looks like an electro as well?
It's definitely an electro with the negative facing the right of the picture. The pic I found of a gutshot from another thread also has an electro in that spot:

https://i76.photobucket.com/albums/j6/I ... Gear/2.jpg

What schematic are you using?

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Post by Whoismarykelly »

95strat wrote:In case anyone wants another guts shot here's a Mayo that been "Pinked" up for auction: https://cgi.ebay.com/Skreddy-Pedals-Pin ... 1|294%3A50

I would love to buy a PF, but will have to build one since they are so overly priced now.

If anyone looks at the pic can you tell me what the big yellow cap is? According to the schematic there's only one electrolytic cap, but that yellow one looks like an electro as well?
It should be a 10uf electro. The Pink Flesh sounds like it does a lot because of the big 10uf input cap as found in the ram head.

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Post by 95strat »

I'm using the schematic at the top of the thread. I know it's for the Mayo, but from what I've read I don't see where you would place another electro. Of course I'm pretty new to all of this so I'm sure I'm missing something.

The only place that makes sense to me is C1 at the input.

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Post by Whoismarykelly »

95strat wrote:I'm using the schematic at the top of the thread. I know it's for the Mayo, but from what I've read I don't see where you would place another electro. Of course I'm pretty new to all of this so I'm sure I'm missing something.

The only place that makes sense to me is C1 at the input.
Yeah you aren't adding an extra cap, youre just subbing the 10uf for the .1uf although there should be more changes than just that to make a mayo into a pink flesh.

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Post by MWichni »

Skreddy wrote:
tschrama wrote:Hi,

I made a few versions, all with BC550C transistors.. (selected Hfe = 580/620)...I haven't found any 2N5088, but I would love to try those.. I finally build one version with transistor sockets, so I can experiment a bit more, but I haven't done that yet...

anyways, the circuit sound great, lot's of sustain, I love the 'flat EQ' switch, that I use alot.. the 220nF caps might be a key ingredient for the circuit..

goodluck,
Thijs

PS
I would love to build a Pink Flesh... is that OK with Skreddy? Someone has a circuit?
To make a Pink Flesh workalike, the short version (there may be more to it than this, such as the signature hard-to-find transistors, but use your ears) is to substitute a 10uf for the input cap and tune the tone stack to "flat/midrange hump" instead of "scoop/flat." Which basically means you'll want to use .0047uf caps on both the highpass and lowpass sides and then switch in an extra .0047uf on the highpass side for the "hump" version. And also increase the size of the cap "Cx" that's always in play in parallel with the tone stack to smooth out the fizz (220pf - 470pf or use your ears, as this depends on lots of factors like the type of transistors and capacitors you use, etc.).

Also add a 100R resistor after the power-polarity diode Dx (schottky or germanium) to increase the effectiveness of the power-supply filter cap C15.
If you want to know what exactly is needed to change mayo into a pink flesh go to the sixth page of this topic.
Cheers. :wink:

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