Wednesday, April 29, 2015
Dan Armstrong Green Ringer
Here's another Dan Armstrong effect. It's part ring modulator (when playing chords) and part octave (when playing on the neck pickup, high on the fretboard with the guitar tone control down). For the clearest octave effect, match the diodes as closely as possible for forward voltage. It might also be worth matching the 47nF caps and the 10K and 22K resistors.
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Oh, I forgot about this one! You can tag it, it's good to go
ReplyDeleteAwesome! Thanks man
DeleteHi all,
ReplyDeleteIs this effect suitable for Bass?
could you please do this?
ReplyDeletehttps://1.bp.blogspot.com/-yeBYWTMN8p0/WEiOU3hacYI/AAAAAAAAArI/QQbIM2X-BA8t1N0iqv_r3LRfwb2A1akHgCLcB/s1600/Earthquaker%2BDevices%2BTentacle.png
its similar to the green ringer with some change values
Follow the schematic I posted on FSB and you'll be able to build it on this layout. The only thing you'd need to add is a 100pF cap from input to ground. The rest of the circuit topography is the same.
Deleteif I want to discard the volume pot assuming the output reaches unity, then volume 3 would be the "new" output and volume 1 doesnt mind, right?
ReplyDeletebtw great page, greetings from Argentina
Correct! And thanks!
DeleteHi! Dumb question probably but - where is 'out' in this circuit? Is it on volume 2nd lug?
ReplyDeleteYes it is. Though the volume pot is optional. If you don't want to include it, out would be the volume 3 pad.
Deletei dont understand how this layout is correct. i checked to make sure no connections were bridged. tried different diodes and still nothing. my main question is why is the output connected to the emitter? ive never seen this done before. in my experience the emitter is hooked to ground and the collector is the output.
ReplyDeleteThis comment has been removed by the author.
ReplyDeleteThe sensitivity of the circuit is fixed. It also lacks the simply limiting found on a number of other "better-behaved" octave-up units. To remedy this, do the following.
Delete1) Replace the 6k2 resistor from Q1 with a 10k pot, one outside lug going to Q1 and the other to ground. Connect a 10uf cap from the wiper to ground (+ terminal of the cap connected to the wiper). As the wiper is moved toward the emitter of Q1, this will increase the gain of that stage, to match the boost-level needed to get good octaving.
2) Because increasing the gain from stock will alter effect/bypass volume-balance, you'll need to add a volume control. The posted drawing shows a 47k resistor to ground and an add 100k volume pot. Remove the 47k resistor (more about this in a moment), and use a 47k log pot for output volume. To avoid situations where the volume is turned down so much that you mistakenly think something's wrong with the pedal, stick a 2k2-4k7 resistor between the ground lug of the pot and ground so that you can turn down but never "off".
3) Germanium diodes will yield more dependable octaving than silicon, but Schottky will be even better. They will also tend to reduce the crossover clipping that silicon introduces.
4) Many of the better octave-up units will include a pair of back-to-back diodes near the output. People mistakenly think these are responsible for the "fuzz". While they DO add a wee bit more clipping, if you remove them, you're still left with PLENTY of fuzz. So why are they there? Octave doublers multiply ALL frequencies x2, and at the initial pick attack, that also includes a lot of harmonics. The doubling of the note itself kind of disappears in the midst of that "harmonic hash", and takes a moment or two to emerge/bloom as the harmonics die down. But so does the volume level. The diode pair imposes a ceiling on the output level such that the signal SEEMS to remain constant for a bit, while the octave comes out of hiding. So, install a back-to-back pair of silicon diodes where that 47k resistor used to be. You can remove the "fizz" that such diodes might add by using a small-value resistor (100-470R) between ground and the ground-side end of the diodes. A small-value capacitor (680-2200pf) in parallel with the added diodes+resistor will also help. I've done all of this and it provides a much better Ringer.
(sorry for the double post. Couldn't see how to edit the first one.)
You could make a more better PCB Layout and share it. An image is worth a thousand words!
DeleteD1 & 2 = 4148 or another two 4001?
ReplyDelete4148s will work
Delete