14 posts
Check this out. A new way to add 3 clipping options. I use a 3 way "on-on-on" switch for 3 clipping options. This makes sense though... the LEDs re in circuit all the time but either of the diodes would clip before them so the LEDs would not work unless both diode sets were out of the circuit. Plus this uses the more common "on-off-on" switch.
http://www.muzique.com/news/diode-clipping-switch/
Good point H but the Landgraff mod (and the Langraff deluxe) allow for assymetrical clipping options. Can this be done with the mod you posted?
The ultimate clipping mod has to be the one posted on the BYOC forum that used an 8 switch DIP and 8 different clipping options that could be mixed and matched.
I'll try and find the post and put a link up.
FYI, my screamer has the Landgraff deluxe mod with Germanian diodes/symetrical LED's/asymetircal LED's as the clipping options. These are mounted on a seperate (stripboard) PCB and all the diodes are socketed so I can swap diodes at will.
Same horse, different jockey I suppose.
I saw a post over at BYOC that stated that different colour (color) LED's clip at different voltages. Could be worth looking into in order to smooth out or be more aggresive with the gain.
Just a thought... Asymmetry, in the circuit Howie posted, can be accomplished really easily. Add different types of diodes in each clipper (i.e. a Red/Green LED in the LED version, a 1N914/1N4148 in the silicon one, and a 50 ohm resistor in series with one of the diodes in the germanium section... or two different germaniums with slightly different turn on voltages...
It's quick and easy to "unbalance" these clippers. If you want a bit less "buzz" from these things, add a 50, or larger, ohm resistor between the bottoms of these diodes and the ground... the larger the resistor the less distortion you'll end up with, but it'll be a lot "crunchier".
Dar
yep, Dar beat me too the punch. ANY combination of different clipping devices will provide asymmetric clipping. Unless of course by pure fluke (or preplanned knowledge) you put different items on each side that just happened to have exacly the same ratings.
Mild Asymmetric is "generally" regarded as the most tubelike. But, one popular option at BYOC is one diode on one side and NOTHING on the other, which would be pretty asymmetric! As always, depends on what you want. I am buying a bunch of 1N34A's right now because I want to test several combos of them. They are "generally" speaking one of the smoother clipping options. And you can always parallel them for more volume... (higher threshold)
interesting post Howie. 1N34A's ? I have about 80 of 'em.
I only needed 8 but apparently , they sold them in increments of 10.
Guess I can start messing around with that.
Thanks for sharing.
Taking notes...
Sam,
In my Screamer clones I build, I'll spend the most time working with different variations of Germaniums (1N34A), LEDs and Mosfets. Germaniums seem to provide the smoothest clipping, mosfets the most "tube like" response to volume and dynamic (picking) changes etc. LEDs as crunchy in some designs, smoother in others.
Experimenting with 1N34As could be things like 1 each way, 1vs. 2 (asymmetric) 2 vs 2 in parallel, etc. Some guys are going further... 2 vs. 3 for higher clip threshold,still asymmetric.. blah blah blah. I'm going to run wires out of my BYOC screamer kit and onto a breadboard where I can play with lots of clipping options and won't solder the final 3 in til I decide what works best for different things
good info Howie.
I'm not a electronics wizard but I see your point.
Breadboards can be very useful when it comes to trying out new stuff.
Might give that a try sometimes.
in these OD pedals, there are many other factors involved in their "sound" but the clipping section is one big element of the "character" of them.
The SRB 808 I have sounded significantly different in the different clipping modes it offered. Even one of the mods at BYOC says that clipping options don't SOUND different if you adjust the levels to compensate for their varying forward voltages, but most people don't agree with this.
The most common clipping use (standard in the Screamers) is diodes. The knock on diodes is that they FIZZ as the note decays. Mosfets are widely believed to offer the most "tube-like" clipping. VERY pick responsive, etc. Germaniums are considered the smoothest. Is it because with the lowest forward voltage of any of these options, they compress more? Or, are germaniums really smoother? LEDs sound the most crunchy... yet they are used in some of the smoothest pedals you'll hear.
So I feel they make a difference, but are part of a whole.
If you want to experiment with different clipping options, Get a small piece of stripboard instead of breadboard and put some SIP sockets in it. This way, you'll be able to swap LED's, Germaniums or whatever you want withuot the grief of de-soldering each time. The three options in my screamer are socketed with 2 symetric and 1 asymetric options. These are wired to a DPDT switch (on-on-on) then to the PCB. I'll post some close up Photo's later today.
Spud,
I was going to do it that way, but on my first one, I want to really check out every option I might consider in a format that I can test different gain levels, different amp settings, different guitars, etc, all without having to keep switching things in and out. Once I know which options I like best, I'll go to strip or vero. But I agree, if I only wanted to try 4-5 options, I'd probably go straight to a strip board with sockets.
If you think about it Howie, you can always set up a small, "out of the casing" rig to test different optins. With a larger piece of stripboard and say, an 8 way mini DIP switch, you can then socket 8 different options and just flick them in and out at will to test them. DIP switches are peanuts to buy (I have a bunch of 4/6/8/12 way ones that came out of old A/C pcb/s that I'll post to you if you want), as are SIP socket strips (Small Bear). A large enough piece of stripboard to do about 8 of these projects/experiments is only $2.
WTF are you waiting for dude :P ;).
Here you go.
http://i229.photobucket.com/albums/ee21/andy_dobson/Screamer1.jpg
http://i229.photobucket.com/albums/ee21/andy_dobson/Screamer2.jpg
http://i229.photobucket.com/albums/ee21/andy_dobson/Screamer3.jpg
http://i229.photobucket.com/albums/ee21/andy_dobson/Screamer4.jpg
Here's the schematic for this.
Tnanks for sharing Spud. Like you said a good way to test out different clippings.
