Advice for choosing a basic distortion effect to build need

[kit102]

Yeah, I used the 2N7000s instead of the BS250s as I couldn't find any of the latter in Australia. I would love to solder in some sockets, and that would probably fix the problem. I've always suspected I might be frying them.. but anyway, I have no idea where to get any sockets. Altronics would be a good place to look, but I couldn't find any online..
........
Thanks for your help.

I did build the Obsidian Overdrive and it works!!

I built the pedal with BS170, which is a N-channel MOSFET (2N7000 is N-channel too) . If you are using the circuit with BS250, then you MUST change the polarity of the battery supply( noted that it shows a -9V in the circuit diagram. So, connect power supply to a +9V) , and the polarity of capacitors( just turn around the three caps, - to +, and + to -). Than, change the collector and emmiter of the transistor to the other way round too!! Than you will hear the pleasure distortion!^0^

PS: sorry for my grammatic errors  ,  i am not good in english

[robbiemcm]

Yeah, I've done all that kit102, it still doesn't work. After I did that I started getting a sound out of it, but now it's squealing and making odd noises..

[robbiemcm]

Uh.. with the Easy Drive.. is that really a 22uF capactior to ground from the gain pot? Seems like a rather odd value to have there considering all the other low value ones. It seems as though a single dot could have easily been but off that was meant to be before it. Just seems weird, a single capactior of that would cost me $1.15 whereas all the others are costing me $0.18

Just wanted to be sure..

[Joe]

Yes, but the voltage rating can be very low (6V), so get the cheapest you can find. Those are good parts to salvage, you can get a lot at once from old VCR's etc, and they are easily removed.

[robbiemcm]

Can I use a 25V electrolytic capacitor (25V is the lowest I can find) for the 22uF because if I bought 10 of those they would be $0.20 each. Then I'd have some spares and I could make another Easy Drive for a friend, and I'd also have more another set of spare components.

[Eric H]

Can I use a 25V electrolytic capacitor (25V is the lowest I can find) for the 22uF because if I bought 10 of those they would be $0.20 each.

Those will work fine.

-Eric

[robbiemcm]

Alright, I built it on breadboard and it sounds good. However as I didn't use the 2N5089 I'm pretty sure it doesn't sound as the circuit was designed.
PN100: Great fuzzy, distortion sound to it.. but there is a huge amount of background noise.. unbearable.
BC549: Literally no background noise, but seems to be more like a clean boost, there is only a little distorition coming through. This distortion is a little more noticeable when you play chords. Sounds good so I'd be happy to go with this, but it would be nice to get a little more distortion out of it.

Also, the gain pot seems to do nothing. Other than what seems a slight change in tone, there is no real noticeable effect. Is this because I'm using the BC549? Could the transistor be re-biased so that it gives a little more overdrive and also so that the gain pot does something?

I forgot to try the 2N3904, I'll plug it in there tomorrow after my economics and physics tests and post back here.

[robbiemcm]

Well, I can't get much (it's actually close to nothing) gain out of the Easy Drive. I suspect it has something to do with how the transistors are biased, as I am using different transistors (can't get hte 2N5089). Any hints anyone?

I plugged in all the transistors I had before I noticed something. I purchased 50 transistors.. but wait.. there's only 40 here. 10 of these: PN100, PN200 and BC549C. But what's that? The other 10 (still leaving me 10 short) are made up of what appears to be.. 2 BC559C, 2 BC559B, 2 labelled C550 (maybe the B at the start is left out), 1 labelled C558B and 3 labelled 559C (almost impossible to make out) but these ones look like they are completely different to the other BC559Cs. What the hell is going on here? I suppose he just forgot to put in the 10 2N3904 transistors (the ones that might actually work better in there) and the guy seemed to just make up what's supposed to be 10 BC559s out of lots of random things. I would have expected this from Dick Smith, but not from Altronics. That is one annoying point of their transistors behind the counter scheme, I'd at least make sure I had all the right bits. I wonder if I should go complain and get my 10 2N3904 transistors (still wondering what the random ones are meant to be) or should I just forfeit the $3 or $4 for these. I don't think I even have the receipt anymore. Another odd thing is that the C558B seemed to work okay in the Easy Drive, whereas the others didn't (I knew that what's meant to be the equivalent of the 2N5088 wasn't going to work in there, I just tried everything when trying to figure out what the hell I'd managed to get..)

[robbiemcm]

Sorry for my third post in a row, but important update. I can get a good amount of the gain from the P100 (which I was told would be the closest I could get). The unbearable background noise I think is actually it just amplifying an annoying noise that is coming from my guitar or lead, or somewhere. It's not perfectly clean, but maybe that could be solved if there was some modification that could be made to the circuit allowing for the P100. Either way, the gain pot still does nothing, maybe this could be solved aswell if some extremely nice person, knowing what they were doing, tried out a P100 in a version and was able to give me some info

[octafish]

You got the pinouts correct right? BC549's should work in there fine. BTW the A B and C suffixes tell you in the Hfe (gain) is A low for the device B medium for the device or C high for the device. The easiest 5088 substitute to get in Aust is the BC549C.

The pn100 datasheet: http://www.uoguelph.ca/~antoon/gadgets/pn100.html

The bc549 datasheet: http://www.ushasemi.com/pdf/Transistors/BC549.pdf

and a cool pinout site: http://hamradio.lakki.iki.fi/new/Datasheets/transistor_pinouts/

As you can see, if you didn't already know, the pn100 and bc549 should have the flat edge facing in opposite directions to be inserted correctly.

P.S. hmm i just read your previous post and you said the bc549 worked but was clean. I'm at a loss. I'll leave my original post as is though because those datasheets are handy links.

[amonte]

How does the EasyDrive and the Muffer sound?  I was thinking of doing a simple build tonight, but I want something a bit more crunchy than a TS style pedal.  I've got a Reverend Drivetrain and Digitech Bad Monkey - both are nice, but seem better suited to lead playing. 

Anyone have any clips?  My original plan was to build something like a modded Electra - single transistor with hard clipped diodes at the end.  I also gave some thought building something around a single MOSFET with hard clipped diodes.

[mac]

try the red fuzz at http://www.generalguitargadget.com
well recorded sound demos available.
very similar to an ibanez fat cat but with less parts. the red leds make the crunch.

mac

[petemoore]

  High Gain/Low Noise
  if it says that at the top of the data sheet like 2n5089, NTE47, MPSA18 's do, it's worth a try, if the EZ Drive is the circuit you're referring to.
  1 high gain transistor does all the amplifying, and the diodes limit the gain, clipping the signal. Few parts, does tricks, slick!
  Because discussion included noise/gain terms, you could build a Darlington [sockets in perf with 3 leads?] and that would gain for sure, I don't remember seeing reports of usage...

[robbiemcm]

Well, I'm pretty happy with it. The main thing I can't understand is why the gain pot does absolutely nothing..

[Joe]

Make sure the 22uF capacitor goes to the center lug of the 1k gain pot. It isn't a real smooth gain control, but should lessen the gain when turned down.

[robbiemcm]

Yeah, that's how it was when I made it. And after that did nothing I decided to randomly make it so that the Transistore went to the centre lug of the pot and ground and the capacitor to the others. That seemed to oddly enough reduce the gain when it was at half way, but still only slightly. So no configuration of the gain pot is going to change anything with it, could someone at least say whether or not it is possible that the P100 bias could be out considering it's a different transistor, and whether this could be causing the gain pot to have little to no affecton gain.

[criss]

Sounds like your working hard at it . Just keep trying different trans . On my multi face build i tryed tons of diff trans and cap combos , i guess thats the great thing about useing sockets for your input / out put caps etc  .

If you get the chance try the multi face project its a easy build and you can get some exellent fuzz .

http://www.runoffgroove.com/multiface.html

[8mileshigh]

Robbie,

After wrestling with my PNP germanium fuzz face, which I still can't get working for some reason fom the General Guitar Gadgets layout, I decided to to try the NPN silicon verson from the layouts section here and it worked first shot and sounds pretty damned good with the fuzz dimed.     I used 2N2222 transistors.

This may not be the sound you're after but it does sound better than the Tweak-O, which was also my first build.  It give me a fanststic Maria Maria (Santana) tone with my SG.

Now, if I could just get my germanium circuit working.  Think I'll start from scratch tonight 

[amonte]

That Red Fuzz sounds great!  Just what I'm looking for.  Only I don't have any LF351's lying around.  Do you think if I substitued a BJT gain stage for the IC that it would have a negative impact on the sound?

[robbiemcm]

Well, I still like the sound, but I'm also still confused as the why the gain control doesnt work. I might just shove a resistor down there and not bother with a gain control, but it would have been nice to have one