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It took me long enough, but here's my first finished design from top to bottom. Quite a simple schematic, not particularly based on anything and I'm pretty happy with it!
See what you think!


Video:
https://www.youtube.com/watch?v=VqUlyEowUzE&t=3s

So my mate picked up this sony tc-133 tape recorder/player box, and its a bit shoddy but, man.
When you clip this thing it gives a great smooth distortion/saturation which'd be great for a guitar pedal, the only problem is.. I don't understand a lick of it. I wouldn't expect a great deal of people here too either..


https://ibb.co/iid7ka

I've heard transformers can do some great saturation sounds, but I have no idea if that's whats causing it in this case. I'm interested to know whats actually clipping and distorting so nicely, and see if it can be applied in a pedal (even it was over 9v).

Not sure what more information you'd need so, if there's anyone who can decipher this mystery, it would be very educational.

Cheers

So a quick introduction on what I'm working on, you'll see some similarities in the design to a rangemaster. Although this isn't built to be a boost pedal at the start of a chain, this is to offer a drive at the end of my pedal chain, as an alternative to an amp overdrive. I felt I could customize a lot more how my signal is being driven this way and just have a nice touch of distortion over everything to add colour, like a cranked valve amp, but with a couple adjustments to frequency response.

So what I have is sort of a slightly cocked wah/bandpass fuzzy driven overdrive, I suppose. Here's the simply drawn schematic -



This works great when my guitar goes straight into it. However since this is going at the end of my pedal chain, I thought I'd test it with another effects pedal that I use - "Mooer Elec Lady" flanger. Like I said the drive is last in the chain so the signal goes to the flanger and THEN the drive. So when I turn the flanger on, I get a very nasty high end distortion ruining the tone of the drive completely. If you notice the drive design it has a 10nf cap grounded to make a low pass filter before anything else can be affected, so I'm a bit confused. I thought it may be an impedance issue, so I added a buffer, the TS9 input buffer to be exact..





The issue I had with this, is after the buffer, I add in the 10nf cap to ground and it really doesn't change the frequency response much at all, even after trying a 10uf cap to ground just to test it wasn't my breadboard, it just reduces the volume more than anything really, not much change in the frequencies. I'm looking for a way to solve/understand whats happening.

I tried to add the drive circuit in anyway, I needed to add a resistor in the signal chain of about 20k to feed the correct amount of signal into the drive transistor, and it does help some what, but I can no longer make a low pass/high pass filter like I did in the original design, or at least, don't know how to rectify the signal to be able to do so.

I'm somewhat uneducated on the actual theory of electronics so I thought I'd ask to see what the issue might be. I can upload some sound samples if necessary.

I'm using BC109 transistors by the way!

Thanks for your time!

So the standard hammond 1590b and 1590bb are just too plain and overused to my eye. I've been searching around everywhere for sheet metal enclosures and just generally enclosures with different looks to them. I've found a few sheet metal enclosures, but they aren't really the dimensions I'm looking for. I actually wouldn't even mind an enclosure like the 1590bb with a bit more height and much less rounded edges, something a bit different to the norm..

Is there any direction/website you guys can point me to?

I am UK based, by the way.

So, I have followed the Fuzz Face Silicon Circuit, and compared it to a few others, like Madbeans Hipster pedal and the like. Heres the one I used...


I started this on breadboard with 2n4401s, but I had tried 2n2222s and have now swapped to 2n5088s, with no noticeable difference..
I have now soldered this on perfboard, but I'm getting oscillation - "dolphin noises" no matter what I do. I have tried caps between Base and Collector on both transistors at the same time with no luck. I have tried resistors between transistors to weaken the gain with no luck, and swapped a couple collector resistors, even when I back off the fuzz knob, it still oscillates. This leads me to believe it is not the circuit thats the problem, but possibly a component or something of the sort.

Here are the voltages I'm getting (I know that Q2's collector is biased way off, but should that be causing oscillation??)

Q1
E  =  0
B  =  0.53
C  =  1.62

Q2
E  =  1
B  =  1.6
C  =  1.8

(These were on breadboard with the 2n4401s, but even on perfboard with 2n5088s, they are very similar)

https://www.dropbox.com/s/ia0cvgnjj7z3w44/20170107_195948.jpg?dl=0



Check this audio sample out, you can hear me back off my guitar volume, and then the fuzz knob soon after...
https://www.dropbox.com/s/b0k9465pf14yc5u/Oscillation.mp3?dl=0

This is on perfboard, so I don't think I can blame the breadboard or anything around that as its making exactly the same noise as it did on breadboard. I used the 2n5088s, they were from China on ebay but I'm not sure how much that would affect anything? Theres no volume pot if that changes anything, but I tried a 100k on the breadboard just to see if it helped, it did not. Also the ceramic 10nf capacitor is TINY, could this be a result of it not being able to take the voltage/current? I'm not sure on the power rating of it.

If it isn't the transistors, all I can think to blame are my ceramic caps which I don't entirely trust, or my jacks, which are meant to be stereo, but don't look like any other stereo jacks I've seen. But I can't imagine them causing oscillation? this has been bothering me for months, thought it would have been a more common occurrence, but if it isn't, then surely I have something bad? I don't like blaming equipment, but I've shown you what I've done and if everything looks as though its in order, what is there left to blame?